Patent Publication Number: US-11643884-B2

Title: Elevator with a tiltable housing for lifting tubulars of various sizes

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional of and claims priority to U.S. patent application Ser. No. 16/674,247 (now patented as U.S. Pat. No. 11,008,820) filed on Nov. 5, 2019 by Jan FRIESTAD et al., and entitled “ELEVATOR WITH A TILTABLE HOUSING FOR LIFTING TUBULARS OF VARIOUS SIZES,” which claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Application No. 62/756,421, entitled “ELEVATOR WITH A TILTABLE HOUSING FOR LIFTING TUBULARS OF VARIOUS SIZES,” by Jan FRIESTAD et al., filed Nov. 6, 2018, of which both are assigned to the current assignee hereof and are incorporated herein by reference in their entireties. 
    
    
     TECHNICAL FIELD 
     The present invention relates, in general, to the field of drilling and processing of wells. More particularly, present embodiments relate to a system and method for manipulating tubulars during subterranean operations. 
     BACKGROUND 
     Top drives are typically utilized in well drilling and maintenance operations, such as operations related to oil and gas exploration. In conventional subterranean (e.g., oil and gas) operations, a wellbore is typically drilled to a desired depth with a tubular string, which can include drill pipe and a drilling bottom hole assembly (BHA). Casing strings can be assembled and installed in the newly drilled portion of the wellbore. During the subterranean operation, a tubular string (e.g., tubular string, casing string, production string, completion string, etc.) may be supported and hoisted about a rig by a hoisting system for eventual positioning down hole in a well. The top drive along with an elevator and a pipe handling system may be used to manipulate tubular segments and tubular strings to extend the tubular string into the wellbore or retrieve the tubular string from the wellbore. 
     When the tubular string is being extended into the wellbore, a pipe handling system may manipulate tubulars (e.g., single, double, or triple stands) from a pipe storage area (e.g., vertical or horizontal tubular storage) to the top drive via assistance of an elevator. The tubular can be connected to the top drive, which may manipulate the tubular to be positioned over and then connect the tubular to a tubular stub extending from the wellbore. When the tubular string is being retrieved from (or “tripped” out of) the wellbore, a tubular string can be hoisted by the top drive unit and tubular segments (e.g., single, double, or triple stands) can be disconnected from a proximal end of the tubular string via the top drive and manipulated to a pipe storage area (e.g., vertical or horizontal tubular storage) via assistance by the elevator and the pipe handling system. 
     However, due to the various diameters of tubulars that may be needed during the subterranean operation, the elevator is normally reconfigured during the operation by replacing latching jaws in the elevator with jaws configured to accommodate different size tubulars. This reconfiguration is normally performed manually by rig operators. This manual process of reconfiguring the elevator when different size tubulars are needed takes up valuable rig time and reducing this impact on rig time can be beneficial. 
     SUMMARY 
     In accordance with an aspect of the disclosure, a system can include an elevator configured to move a tubular, the elevator including: a housing defining a central bore configured to receive the tubular therein; a first latch including first and second jaws, with each of the first and second jaws being coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the first and second jaws are in the engaged position, engagement portions of the first and second jaws are positioned in the central bore on opposite sides of, with respect to each other, a central axis of the central bore and define an opening of a first diameter; and a second latch including third and fourth jaws, with each of the third and fourth jaws coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the third and fourth jaws are in the engaged position, engagement portions of the third and fourth jaws are positioned in the central bore on opposite sides of, with respect to each other, the central axis of the central bore and define an opening of a second diameter which is different than the first diameter, where the first jaw is fixedly attached to a first drive shaft and the first drive shaft is rotationally attached to the housing, where the third jaw is fixedly attached to a third drive shaft and the third drive shaft is rotationally attached to the housing, and where the first and third drive shafts independently rotate the first and third jaws, respectively, about a first axis. 
     In accordance with another aspect of the disclosure, a system for conducting subterranean operations can include: an elevator configured to move a tubular, the elevator including: a housing defining a central bore configured to receive the tubular therein, the central bore having a central axis; and a link interface system configured to rotate the housing up to greater than 90 degrees about a housing axis. 
     In accordance with another aspect of the disclosure, a system for conducting subterranean operations can include: an elevator configured to move a tubular, the elevator including: a housing defining a central bore configured to receive the tubular therein; a first latch including first and second jaws, with each of the first and second jaws being coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the first and second jaws are in the engaged position, engagement portions of the first and second jaws are positioned in the central bore; a second latch including third and fourth jaws, with each of the third and fourth jaws coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the third and fourth jaws are in the engaged position, engagement portions of the third and fourth jaws are positioned in the central bore; and an electronics enclosure within the housing, with the electronics enclosure configured to be ATEX certified or IECEx certified according to ex zone 1 requirements. 
     In accordance with another aspect of the disclosure, a system for conducting subterranean operations can include: an elevator configured to move a tubular, the elevator including: a housing defining a central bore configured to receive the tubular therein; a first latch including first and second jaws, with each of the first and second jaws being coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the first and second jaws are in the engaged position, engagement portions of the first and second jaws are positioned in the central bore on opposite sides of, with respect to each other, a central axis of the central bore and define an opening of a first diameter; a second latch including third and fourth jaws, with each of the third and fourth jaws coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the third and fourth jaws are in the engaged position, engagement portions of the third and fourth jaws are positioned in the central bore on opposite sides of, with respect to each other, the central axis of the central bore and define an opening of a second diameter which is different than the first diameter; and an electronics controller disposed in an electronics enclosure within the housing and configured to control the elevator to handle the tubular. 
     In accordance with another aspect of the disclosure, a system for conducting subterranean operations can include: an elevator configured to move a tubular, the elevator including: a housing defining a central bore configured to receive the tubular therein; a first latch including first and second jaws, with each of the first and second jaws being coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the first and second jaws are in the engaged position, engagement portions of the first and second jaws are configured to form a first frustoconically shaped portion positioned in the central bore and surrounding a central axis of the central bore, where the first frustoconically shaped portion defines an opening of a first diameter; and a second latch including third and fourth jaws, with each of the third and fourth jaws coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the third and fourth jaws are in the engaged position, engagement portions of the third and fourth jaws are configured to form a second frustoconically shaped portion positioned in the central bore and surrounding the central axis of the central bore, where the second frustoconically shaped portion defines an opening of a second diameter which is different than the first diameter, where the first frustoconically shaped portion includes a first gap between the first and second jaws when the first latch is in the engaged position, and where the second frustoconically shaped portion includes a second gap between the third and fourth jaws when the second latch is in the engaged position, and where the first and second gaps are parallel to the central axis, and the first gap is circumferentially offset, relative to the central axis, from the second gap. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features, aspects, and advantages of present embodiments will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein: 
         FIGS.  1 - 3    are representative schematics of a rig being utilized for a subterranean operation (e.g., drilling a wellbore) with a top drive and an elevator, in accordance with certain embodiments; 
         FIG.  4    is a representative perspective view of an elevator, in accordance with certain embodiments; 
         FIG.  5    is a representative perspective view of an elevator with four latches for handling tubulars, the latches being in disengaged positions, in accordance with certain embodiments; 
         FIG.  6    is a representative cut-away perspective view of an elevator with four latches for handling tubulars, the latches being in various engaged or disengaged positions, in accordance with certain embodiments; 
         FIG.  7    is a representative cut-away perspective view of an elevator with four latches for handling tubulars, the latches being in engaged positions, in accordance with certain embodiments; 
         FIG.  8 A  is a representative cross-sectional view of an elevator with four latches for handling tubulars, the latches being in engaged positions, in accordance with certain embodiments; 
         FIG.  8 B  is a representative detailed cross-sectional view of a portion of the elevator in  FIG.  8 A , in accordance with certain embodiments; 
         FIG.  8 C  is a representative detailed cross-sectional view of the portion of the elevator shown in  FIG.  8 B  with an alternative configuration of latches, in accordance with certain embodiments; 
         FIG.  8 D  is a representative cross-sectional view of an elevator with four latches for handling tubulars, the latches being in engaged positions, in accordance with certain embodiments; 
         FIG.  9    is a representative top view of an elevator similar to the elevator in  FIG.  7   , in accordance with certain embodiments; 
         FIG.  10    is a representative cross-sectional view  10 - 10  of an elevator with at least two latches for handling tubulars, the latches being in engaged positions, in accordance with certain embodiments; 
         FIG.  11    is a representative cut-away perspective view of an elevator with four latches, including rotary actuators, for handling tubulars, the latches being in various engaged or disengaged positions, in accordance with certain embodiments; 
         FIG.  12    is a representative top view of an elevator similar to the elevator in  FIG.  11    for handling tubulars, the latches being in engaged positions, in accordance with certain embodiments; 
         FIG.  13    is a representative cross-sectional view  13 - 13  of an elevator with at least two latches for handling tubulars, the latches being in engaged positions, in accordance with certain embodiments; and 
         FIG.  14 A  is a representative cut-away perspective view of a link interface of an elevator for handling tubulars with components of the elevator other than the link interface components removed, in accordance with certain embodiments. 
         FIG.  14 B  is a representative perspective view of an adjustable link interface of an elevator, in accordance with certain embodiments. 
         FIG.  15    is a representative diagram that illustrates rotation angles of the elevator relative to the links, in accordance with certain embodiments; 
         FIG.  16    is a representative detailed cross-sectional perspective view of an elevator with an alternative configuration of latches, in accordance with certain embodiments; 
         FIG.  17    is a representative detailed cross-sectional view  17 - 17  of the elevator of  FIG.  16    with latches in various stages of engagement or disengagement, in accordance with certain embodiments; 
         FIG.  18    is a representative detailed cross-sectional view  17 - 17  of the elevator of  FIG.  16    with latches in an engaged position, in accordance with certain embodiments; 
         FIG.  19    is a representative detailed cross-sectional view  19 - 19  of the elevator of  FIG.  16    with latches in an engaged position, in accordance with certain embodiments; 
         FIG.  20    is a representative enlarged perspective view of a link interface of an elevator with a removable retainer, in accordance with certain embodiments; 
         FIG.  21    is a representative exploded perspective view of the removable retainer of  FIG.  20   , in accordance with certain embodiments; 
         FIG.  22    is a representative front view of a removable retainer aligned with a retainer mount, in accordance with certain embodiments; 
         FIG.  23    is a representative perspective view of a removable retainer aligned with a retainer mount with the retainer mount inserted through a center opening in the removable retainer, in accordance with certain embodiments; 
         FIG.  24    is a representative cross-section perspective view of a removable retainer aligned with a retainer mount with the retainer mount inserted through a center opening in the removable retainer and rotated to engage the removable retainer, in accordance with certain embodiments; 
         FIG.  25    is a representative perspective view a housing of an elevator with latch assemblies removed to show a circular weight sensor, according to certain embodiments; 
         FIG.  26    is a representative perspective view of a circular weight sensor, according to certain embodiments; 
         FIG.  27    is a representative partial cross-sectional view of the circular weight sensor of  FIG.  26   , according to certain embodiments; 
         FIG.  28 A  is a representative side view of a reservoir with a pressure sensor, according to certain embodiments; and 
         FIG.  28 B  is a representative cross-sectional view of the reservoir of  FIG.  28 A , according to certain embodiments 
     
    
    
     DETAILED DESCRIPTION 
     Present embodiments provide an elevator that provides remote actuation of multiple latches to accommodate various diameter tubulars (including tubular stands and tubular strings) and to rotate the elevator relative to a pair of links (or bails) to align the elevator to the tubulars. The elevator comprises rotary actuators for manipulating the latches between engaged and disengaged positions, where a tubular would be latched (or engaged, retained, etc.) when the appropriate latches are in the engaged position and released when the latches are in the disengaged position. The elevator may also comprise a rotary actuator for rotating the elevator relative to the links. The aspects of various embodiments are described in more detail below. 
       FIG.  1    is a schematic view of a rig  10  in the process of a subterranean operation in accordance with certain embodiments which require providing tubulars to and removing tubulars from a top drive of the rig  10 . In this example, the rig  10  is in the process of drilling a well, but the current embodiments are not limited to a drilling operation. The rig  10  can also be used for other operations that require manipulating tubulars. The rig  10  features an elevated rig floor  12  and a derrick  14  extending above the rig floor  12 . A supply reel  16  supplies line  18  to a crown block  20  and traveling block  22  configured to hoist various types of drilling equipment above the rig floor  12 . The line  18  is secured to a deadline tiedown anchor  24 , and a drawworks  26  regulates the amount of line  18  in use and, consequently, the height of the traveling block  22  at a given moment. Below the rig floor  12 , a tubular string  28  extends downward into a wellbore  30  formed in the earthen formation  8  through the surface  6  and is held stationary with respect to the rig floor  12  by a rotary table  32  and slips  34  (e.g., power slips). A portion of the tubular string  28  extends above the rig floor  12 , forming a stump  36  to which another length of tubular  38  (e.g., a joint of drill pipe) may be added. 
     A tubular drive system  40 , hoisted by the traveling block  22 , can collect the tubular  38  from a pipe handling system  60  and position the tubular  38  above the wellbore  30 . In the illustrated embodiment, the tubular drive system  40  includes a top drive  42 , an elevator  100 , and a pair of links that couple the elevator to the top drive  42 . The tubular drive system  40  can be configured to measure forces acting on the tubular drive system  40 , such as torque, weight, and so forth. These measurements can be communicated to a controller  50  used to control various rig systems during the subterranean operation. For example, the tubular drive system  40  may measure forces acting on the top drive  42  via sensors, such as strain gauges, gyroscopes, pressure sensors, accelerometers, magnetic sensors, optical sensors, or other sensors, which may be communicatively linked to the controller  50 . The tubular drive system  40 , once coupled with the tubular  38 , may hoist the tubular  38  from the pipe handling system  60 , then lower the coupled tubular  38  toward the stump (or stickup)  36  and rotate the tubular  38  such that it connects with the stump  36  and becomes part of the tubular string  28 .  FIG.  1    further illustrates the tubular drive system  40  coupled to a torque track  52 . The torque track  52  functions to counterbalance (e.g., counter react) moments (e.g., overturning and/or rotating moments) acting on the tubular drive system  40  and further stabilize the tubular drive system  40  during a tubular string running or other operation. 
     The rig  10  further includes a control system  50 , which is configured to control the various systems and components of the rig  10  that grip, lift, release, and support the tubular  38  and the tubular string  28  during a tubular string running or tripping operation. For example, the control system  50  may control operation of the top drive, the elevator, and the power slips  34  based on measured feedback (e.g., from the tubular drive system  40  and other sensors) to ensure that the tubular  38  and the tubular string  28  are adequately gripped and supported by the tubular drive system  40  and/or the power slips  34  during a tubular string running operation. The control system  50  may control auxiliary equipment such as mud pumps, the robotic pipe handler  60 , and the like. 
     In the illustrated embodiment, the control system  50  can include one or more microprocessors and memory storage. For example, the controller  50  may be an automation controller, which may include a programmable logic controller (PLC). The memory is a non-transitory (not merely a signal), computer-readable media, which may include executable instructions that may be executed by the control system  50 . The controller  50  receives feedback from the tubular drive system  40  and/or other sensors that detect measured feedback associated with operation of the rig  10 . For example, the controller  50  may receive feedback from the tubular drive system  40  and/or other sensors via wired or wireless transmission. Based on the measured feedback, the controller  50  can regulate operation of the tubular drive system  40  (e.g., increasing rotation speed, increasing weight on bit, etc.). The controller  50  can also communicate via wired or wireless transmission to control or monitor the tubular drive system  40  or the elevator  100 . Status information regarding the configuration of the elevator  100  (e.g., configuration of the latches, link interface position, orientation of the elevator  100 , position of the elevator  100 , weight of a tubular held by the elevator  100 , error conditions for the elevator  100 , environment characteristics of elevator  100  interior, etc.) 
     The rig  10  may also include a pipe handling system  60  configured to transport tubulars  38  (e.g., single stands, double stands, triple stands) from a horizontal storage to the derrick  14 . The pipe handling system  60  can include a horizontal platform  62  that can be raised or lowered (arrows  68  in  FIG.  2   ) along elevator supports  64 ,  66 . The pipe handler  60  is shown delivering the tubular  38  to the rig floor in a horizontal position. However, other pipe handlers may be used that deliver the tubulars to the rig floor at any orientation from near and below horizontal orientations to vertical orientations. The elevator  100  can remotely and/or automatically rotate the elevator  100  about the axis  80  to align a central bore of the elevator  100  to the tubulars  38  over a wide range of orientations. The links  44  can also be rotated about axis  82  to increase mobility of the elevator  100  for receiving tubulars  38 . The tubulars  38  can include a box end  39  with a radially enlarged outer diameter relative to an outer diameter of the tubular  38 . The tubulars  38  can also have a portion proximate the box end  39  that has a radially reduced diameter relative to both the outer diameters of the tubular  38  and the box end  39 . The outer diameters of the tubular  38  and the box end  39  can be substantially equal or substantially different from each other. The tubular  38  can have a portion  37  proximate the box end  39  that is radially reduced relative to the box end. 
       FIG.  2    is another schematic view of the rig  10  shown in  FIG.  1   , except that the top drive  42  has been lowered and the elevator  100  rotated to receive the tubular  38  from the pipe handler  60 . One or more latches in the elevator can engage the tubular  38  (e.g., by engaging the box end  39 ) thereby preventing the tubular  38  from exiting the elevator  100  until the latches are disengaged. As seen in  FIG.  2   , the elevator can rotate  70  about the axis  80  relative to the links  44  and the links  44  can rotate  72  about the axis  82 . 
       FIG.  3    is another schematic view of the rig  10  shown in  FIG.  2   , except that the top drive  42  has been raised to hoist the tubular  38  and align it with the stub  36  for connection of the tubular  38  to the tubular string  28 . Once the tubular  38  is aligned to the stub  36 , the tubular drive system  40  can lower the tubular  38  to the stub  36  for connection to the tubular string  28  by rig equipment and/or personnel. It should be understood, that while the elevator  100  and the tubular drive system  40  are shown in  FIGS.  1 - 3    as facilitating a connection of a tubular  38  to the tubular string  28  during an operation to trip the tubular string  28  into the wellbore  30 , the elevator  100  and the tubular drive system  40  are well suited to support other rig operations, such as tripping the tubular string  28  out of the wellbore  30  (e.g., reversing the operations shown in  FIGS.  1 - 3   ), and supporting the weight of the tubular string  28  during rig  10  operations. 
     It should be noted that the illustrations of  FIGS.  1 - 3    are intentionally simplified to focus on the operation of the tubular drive system  40  and the elevator  100 , which is described in greater detail below. Many other components and tools may be employed during the various periods of formation and preparation of the wellbore  30 . Similarly, as will be appreciated by those skilled in the art, the orientation and environment of the wellbore  30  may vary widely depending upon the location and situation of the formations of interest. For example, rather than a generally vertical bore, the wellbore  30 , in practice, may include one or more deviations, including angled and horizontal runs. Similarly, while shown as a surface (land-based) operation, the wellbore  30  may be formed in water of various depths, in which case the topside equipment may include an anchored or floating platform. 
       FIG.  4    is a perspective view of an elevator  100  rotatably attached to ends  46  of a pair of links  44 . The ends  48  of the links  44  can be rotatably attached to the top drive  40 , thereby linking the elevator  100  to the top drive  42 . The elevator  100  can rotate relative to the links  44  about the axis  80  as needed to facilitate handling tubulars (e.g., the tubular  38  or the tubular string  28 ). The housing  102  of the elevator  100  can include a sealed chamber  106  that is sealed from the fluids and debris associated with the harsh environment of the rig  10 .  FIG.  4    shows one of the side panels removed which would be installed during operation of the elevator  100 . The elevator  100  can also include multiple latches  104  that can adapt the elevator  100  to tubulars  38  with various diameters. This example tubular  38  has a box end  39  with a diameter D 9 , a portion  37  with a reduced diameter D 10 , with the remainder of the tubular  38  having a diameter D 8 . 
     The latches  104  are configured to support various tubular diameters. If tubulars  38  (having the largest diameter supported by the elevator  100 ) are to be handled, then all latches  104  would be pivoted to a disengaged position to allow the box end  39  of the large diameter tubular  38  to be inserted through a central bore (with axis  84 ) of the elevator  100  (with a minimal diameter that is larger than the maximum diameter of the box end  39 ) until the reduced diameter portion  37  is positioned in the central bore. The elevator  100  can then be controlled to pivot one or more of the latches  104  into an engaged position which reduces the minimal diameter of the central bore. In this example, only one of the latches  104  may be pivoted to an engaged position adjacent the reduced diameter portion  37 . The engaged latch  104  allows the reduced diameter portion  37  to freely travel through the elevator  100 . However, the engaged latch  104  prevents the box end with diameter D 9  from passing through the elevator  100  because the inner diameter of the engaged latch  104  is less than the outer diameter D 9  of the box end  39 . The tubular drive system  40  can then raise and lower the tubular  38  since the engaged latch  104  engages the box end  39  and prevents it from passing through the elevator  100 . As smaller diameter tubulars  38  are needed, more latches  104  can be pivoted to an engaged position to engage the smaller diameters D 9  of the box ends  39  of the smaller tubulars  38 . Additional latches pivoted to an engaged position forms a smaller inner diameter of an opening through the latches  104  that engage the smaller tubulars  38 .  FIG.  4    shows one latch in an engaged position, with three other latches  104  (each including a pair of jaws) in a disengaged position. 
       FIG.  5    is a perspective view of an elevator  100  with four latches for handling tubulars  38  (which includes handling tubular strings  28 ). The elevator  100  includes the housing  102 , a link interface  222 ,  224  for pivoting the housing about the axis  80 , and multiple latches  110 ,  120 ,  130 ,  140  for managing a diameter of the opening through the elevator  100 . A spacer ring  108  is positioned in the central bore of the elevator  100  and defines the maximum diameter of a tubular  38  that is allowed to pass through the elevator  100 . The latches  110 ,  120 ,  130 ,  140  successively reduce the maximum diameter of tubulars  38  that are allowed to pass through the elevator  100 . Each latch  110 ,  120 ,  130 ,  140  includes a pair of jaws that are rotatably attached to the housing  102 . The first latch  110  includes jaws  110   a ,  110   b . The second latch  120  includes jaws  120   a ,  120   b  (please note that the jaw  120   a  is not shown and the reference numeral is indicating a general position of the jaw  120   a . The third latch  130  includes jaws  130   a ,  130   b . The fourth latch  140  includes jaws  140   a ,  140   b . The latches  110 ,  120 ,  130 ,  140  are shown in a disengaged position with the jaw pairs pivoted away from the tubular  38  in the central bore. Each jaw in the jaw pairs are positioned on opposite sides of the central bore. Therefore, the jaws  110   a ,  120   a ,  130   a ,  140   a , can be positioned on a left side of the central bore (relative to the link interface  222 ) with the jaws  110   b ,  120   b ,  130   b ,  140   b , positioned on the right side of the central bore. The first latch  110  (with jaws  110   a ,  110   b ) is pivoted to an engaged position to capture the largest diameter tubulars  38  within the elevator  100 . The latches  120 ,  130 ,  140  are successively pivoted to an engaged position to capture smaller and smaller diameter tubulars  38 . A link retainer  400  can be removably attached to retain a link  44  to an elevator support  402  once the elevator support  402  has been inserted through an opening in the link  44 . When installed, the link retainer  400  can prevent removal of the link from the elevator  100  until the link retainer is disengaged. A more detailed discussion of the link retainer  400  is given below in reference to  FIGS.  20 - 24   . 
       FIG.  6    is a cut-away perspective view of an elevator  100  with four latches for handling tubulars  38 . The outer portions of the housing  102  have been removed for discussion purposes. The housing  102  can be ATEX and/or IECEx certified per the EX Zone 1 requirements. ATEX is an abbreviation for “Atmosphere Explosible”. IECEx stands for the certification by the International Electrotechnical Commission for Explosive Atmospheres. ATEX is the name commonly given to two European Directives for controlling explosive atmospheres: 1) Directive  99 / 92 /EC (also known as ‘ATEX  137 ’ or the ‘ATEX Workplace Directive’) on minimum requirements for improving the health and safety protection of workers potentially at risk from explosive atmospheres. 2) Directive  94 / 9 /EC (also known as ‘ATEX  95 ’ or ‘the ATEX Equipment Directive’) on the approximation of the laws of Member States concerning equipment and protective systems intended for use in potentially explosive atmospheres. Therefore, as used herein “ATEX certified” indicates that the article (such as the elevator  100 ) meets the requirements of the two stated directives ATEX  137  and ATEX  95  for explosive (EX) Zone 1 environments. IECEx is a voluntary system which provides an internationally accepted means of proving compliance with IEC standards. IEC standards are used in many national approval schemes and as such, IECEx certification can be used to support national compliance, negating the need in most cases for additional testing. Therefore, as used herein, “IECEx certified” indicates that the article (such as the elevator  100 ) meets the requirements defined in the IEC standards for EX Zone 1 environments. 
     Therefore, the enclosure  150  within the sealed chamber  106  of the elevator  100  is configured to meet the standards to be ATEX and IECEx certified according to EX Zone 1 requirements. A hydraulic generator  154  can receive pressurized hydraulic fluid via lines  156  to drive the generator  154 , which can produce electrical energy for powering electrical circuitry (such as electronic processors, and programmable logic controllers PLCs) and storing electrical energy in an electrical storage device  152 . The storage device  152  is shown connected to the enclosure  150 , but the storage device  152  can also be disposed within the enclosure  150  with the generator coupled to the enclosure  150  and the storage device  152  via conductors  158 . The storage device  152  can be a battery that stores the electrical energy, but it can also be a capacitor assembly that couples capacitive devices together in the capacitor assembly to provide electrical energy storage that can operate the elevator for at least 5 seconds if the elevator  100  losses power (e.g., generator fails, loss of pressurized hydraulic fluid to generator, etc.). The at least 5 seconds of Uninterruptable Power Supply UPS capability provided by the storage device  152  assumes that no connection operations occur during the power outage. The storage device  152  can provide power to operate the elevator  100  for up to 10 seconds, up to 15 seconds, up to 20 seconds, up to 25 seconds, up to 30 seconds, up to 40 seconds, up to 50 seconds, up to 60 seconds, up to 2 minutes, up to 15 minutes, up to 30 minutes, or greater than 30 minutes. The capacitor assembly can provide significant improvement in obtaining ATEX and IECEx certifications for the elevator  100 , since a battery requires additional testing per the EX Zone 1 requirements (or standards). 
     Referring again to  FIG.  6   , the example elevator  100  shows the first and second latches  110 ,  120  in the engaged position with the third and fourth  130 ,  140  in the disengaged position. Rotary actuators  212 ,  214 ,  216 ,  218  are coupled to respective latches  110 ,  120 ,  130 ,  140 . The rotary actuators operate to rotate the jaw pairs of each latch  110 ,  120 ,  130 ,  140  into and out of an engaged position. Some of the linkages that couple the rotary actuators to the respective latches  110 ,  120 ,  130 ,  140  are not shown, but one of ordinary skill in the art will recognize the absent linkages necessary to operate the jaw pairs of each latch  110 ,  120 ,  130 ,  140 . The rotary actuator  212  is coupled to the jaws  110   a ,  110   b  through linkage  232 . The jaws  110   a ,  110   b  are rotatably attached to the housing through respective drive shafts. Rotating the drive shafts rotate the respective jaws relative to the housing  102  and relative to the central bore of the elevator  100 . The linkage  232  is coupled to the drive shafts of the jaws  110   a ,  110   b  such that when the rotary actuator  212  is operated, the linkage causes the jaw  110   a  to rotate about its respective drive shaft in a direction that is opposite a direction the jaw  110   b  rotates about its respective drive shaft. Therefore, to operate the latch to an engaged position, the rotary actuator  212  can operate the linkage  232  such that the jaws  110   a ,  110   b  rotate toward each other until they are in the engaged position and engaging the spacer ring  108  (see  FIGS.  5  and  8 A ). To operate the latch to a disengaged position, the rotary actuator  212  can operate the linkage  232  such that the jaws  110   a ,  110   b  rotate away from each other until they are positioned in the disengaged position as shown in  FIG.  5   . 
     The rotary actuator  214  is coupled to the jaws  120   a ,  120   b  through linkage  234 . The jaws  120   a ,  120   b  are rotatably attached to the housing through respective drive shafts. Rotating the drive shafts rotate the respective jaws relative to the housing  102  and relative to the central bore of the elevator  100 . The linkage  234  is coupled to the drive shafts of the jaws  120   a ,  120   b  such that when the rotary actuator  214  is operated, the linkage causes the jaw  120   a  to rotate about its respective drive shaft in a direction that is opposite a direction the jaw  120   b  rotates about its respective drive shaft. Therefore, to operate the latch to an engaged position, the rotary actuator  214  can operate the linkage  234  such that the jaws  120   a ,  120   b  rotate toward each other until they are in the engaged position and engaging a portion of the jaws  110   a ,  110   b . To operate the latch to a disengaged position, the rotary actuator  214  can operate the linkage  234  such that the jaws  120   a ,  120   b  rotate away from each other until they are positioned in the disengaged position as shown in  FIG.  5   . 
     Similarly, the rotary actuator  216  can operate to rotate the jaws  130   a ,  130   b  into and out of an engaged position through the linkage  236 . The rotary actuator  218  can operate to rotate the jaws  140   a ,  140   b  into and out of an engaged position through the linkage  238 . 
     A first drive shaft  162  is fixedly attached to the jaw  110   a , a second drive shaft  164  is fixedly attached to the jaw  110   b , a third drive shaft  166  is fixedly attached to the jaw  120   a , and fourth drive shaft  168  is fixedly attached to the jaw  120   b . The first and third drive shafts  162 ,  166  are rotatably attached to the housing  102  along an axis  90  and rotate the respective jaws about the axis  90 . The first and third drive shafts  162 ,  166  are also adjacent each other along the axis  90 , and laterally spaced apart along the axis  90 . Therefore, a portion of the jaw  120   a  adjacent the third drive shaft  166  does not overlap the jaw  110   a  when the jaws  110   a  and  120   a  are in the engaged position. However, an engagement portion of the jaw  120   a  overlaps and engages an engagement portion of the jaw  110   a  when the jaws  110   a  and  120   a  are in the engaged position. 
     Similarly, the second and fourth drive shafts  164 ,  168  are rotatably attached to the housing  102  along the axis  92  and rotate the respective jaws about the axis  92 . The second and fourth drive shafts are also adjacent each other along the axis  92  and are laterally spaced apart along the axis  92 . A portion of the jaw  120   b  adjacent the fourth drive shaft  168  does not overlap the jaw  110   b  when the jaws  110   b  and  120   b  are in the engaged position. However, an engagement portion of the jaw  120   b  overlaps and engages an engagement portion of the jaw  110   b  when the jaws  110   b  and  120   b  are in the engaged position. 
     The rotary actuator  216  is coupled to the jaws  130   a ,  130   b  through linkage  236 . The jaws  130   a ,  130   b  are rotatably attached to the housing through respective drive shafts. Rotating the drive shafts rotate the respective jaws relative to the housing  102  and relative to the central bore of the elevator  100 . The linkage  236  is coupled to the drive shafts of the jaws  130   a ,  130   b  such that when the rotary actuator  216  is operated, the linkage causes the jaw  130   a  to rotate about its respective drive shaft in a direction that is opposite a direction the jaw  130   b  rotates about its respective drive shaft. Therefore, to operate the latch to an engaged position, the rotary actuator  216  can operate the linkage  236  such that the jaws  130   a ,  130   b  rotate toward each other until they are in the engaged position and engaging a portion of the jaws  120   a ,  120   b . To operate the latch to a disengaged position, the rotary actuator  216  can operate the linkage  236  such that the jaws  130   a ,  130   b  rotate away from each other until they are positioned in the disengaged position as shown in  FIGS.  5  and  6   . 
     The rotary actuator  218  is coupled to the jaws  140   a ,  140   b  through linkage  234 . The jaws  140   a ,  140   b  are rotatably attached to the housing through respective drive shafts. Rotating the drive shafts rotate the respective jaws relative to the housing  102  and relative to the central bore of the elevator  100 . The linkage  238  is coupled to the drive shafts of the jaws  140   a ,  140   b  such that when the rotary actuator  218  is operated, the linkage causes the jaw  140   a  to rotate about its respective drive shaft in a direction that is opposite a direction the jaw  140   b  rotates about its respective drive shaft. Therefore, to operate the latch to an engaged position, the rotary actuator  218  can operate the linkage  238  such that the jaws  140   a ,  140   b  rotate toward each other until they are in the engaged position and engaging a portion of the jaws  130   a ,  130   b . To operate the latch to a disengaged position, the rotary actuator  218  can operate the linkage  238  such that the jaws  140   a ,  140   b  rotate away from each other until they are positioned in the disengaged position as shown in  FIG.  5   . 
     A first drive shaft  162  is fixedly attached to the jaw  110   a , a second drive shaft  164  is fixedly attached to the jaw  110   b , a third drive shaft  166  is fixedly attached to the jaw  120   a , a fourth drive shaft  168  is fixedly attached to the jaw  120   b , a fifth drive shaft  172  is fixedly attached to the jaw  130   a , a sixth drive shaft  174  is fixedly attached to the jaw  130   b , a seventh drive shaft  176  is fixedly attached to the jaw  140   a , and an eighth drive shaft  178  is fixedly attached to the jaw  140   b.    
     The first and third drive shafts  162 ,  166  are rotatably attached to the housing  102  along an axis  90  and rotate the respective jaws about the axis  90 . The first and third drive shafts  162 ,  166  are also adjacent each other along the axis  90 , and laterally spaced apart along the axis  90 . A portion of the jaw  120   a  adjacent the third drive shaft  166  does not overlap the jaw  110   a  when the jaws  110   a  and  120   a  are in the engaged position. However, an engagement portion of the jaw  120   a  overlaps and engages an engagement portion of the jaw  110   a  when the jaws  110   a  and  120   a  are in the engaged position. 
     The second and fourth drive shafts  164 ,  168  are rotatably attached to the housing  102  along the axis  92  and rotate the respective jaws about the axis  92 . The second and fourth drive shafts  164 ,  168  are also adjacent each other along the axis  92 , and are laterally spaced apart along the axis  92 . A portion of the jaw  120   b  adjacent the fourth drive shaft  168  does not overlap the jaw  110   b  when the jaws  110   b  and  120   b  are in the engaged position. However, an engagement portion of the jaw  120   b  overlaps and engages an engagement portion of the jaw  110   b  when the jaws  110   b  and  120   b  are in the engaged position. 
     The fifth and seventh drive shafts  172 ,  176  are rotatably attached to the housing  102  along an axis  94  and rotate the respective jaws about the axis  94 . The fifth and seventh drive shafts  172 ,  176  are also adjacent each other along the axis  94 , and laterally spaced apart along the axis  94 . A portion of the jaw  140   a  adjacent the seventh drive shaft  176  does not overlap the jaw  130   a  when the jaws  130   a  and  140   a  are in the engaged position. However, an engagement portion of the jaw  140   a  overlaps and engages an engagement portion of the jaw  130   a  when the jaws  130   a  and  140   a  are in the engaged position. 
     The sixth and eighth drive shafts  174 ,  178  are rotatably attached to the housing  102  along the axis  96  and rotate the respective jaws about the axis  96 . The second and fourth drive shafts are also adjacent each other along the axis  96  and are laterally spaced apart along the axis  96 . A portion of the jaw  140   b  adjacent the fourth drive shaft  178  does not overlap the jaw  130   b  when the jaws  130   b  and  140   b  are in the engaged position. However, an engagement portion of the jaw  140   b  overlaps and engages an engagement portion of the jaw  130   b  when the jaws  130   b  and  140   b  are in the engaged position. 
     When operating the latches  110 ,  120 ,  130 ,  140 , the first latch  110  is rotated into an engaged position before the other latches  120 ,  130 ,  140 . The second latch  120  can be rotated into an engaged position after the first latch  110  is actuated to the engaged position and before the other latches  130 ,  140  are actuated. The third latch  130  can be rotated into an engaged position after the first and second latches  110 ,  120  are actuated to the engaged position and before the other latch  140  is actuated. The fourth latch  140  can be rotated into an engaged position after the first, second, and third latches  110 ,  120 ,  130  are actuated to the engaged position. With all four latches in the engaged position, (as seen in  FIG.  7   ) the elevator  100  is configured with a minimal diameter opening through the engaged latches  110 ,  120 ,  130 ,  140 . With each successive closure of the latches  110 ,  120 ,  130 ,  140 , the minimum diameter of the opening through the latches decreases. Conversely, as the latches are sequentially rotated from the engaged positions to disengaged positions in reverse order, the minimum diameter of the opening through the latches increases. This allows the elevator  100  to be reconfigured to handle tubulars  38  with a wide range of diameters. The elevator can be automatically reconfigured by the controller  50  and/or processors in the enclosure  150  based on sensor date, and/or manually configured by the controller  50  and/or the processors in the enclosure  150  based on user inputs. 
     Referring now to  FIG.  7   , in addition to the rotary actuators  212 ,  214 ,  216 ,  218  that operate the latches  110 ,  120 ,  130 ,  140 , respectively, the elevator  100  can also include a rotary actuator  210  that operates to rotate the elevator housing  102  relative to the links  44 . The rotary actuator  210  can be fixedly attached to the housing  102  and a drive shaft of the actuator  210  is coupled to the link interfaces  222 ,  224  by linkage  230 . As the rotary actuator  210  rotates its drive shaft drives the coupling  230  and operates to rotate the link interfaces  222 ,  224 , which rotate together relative to the housing  102 . The link interface  222  can include a pair of angled flanges  226   a ,  226   b  disposed on opposite sides of a first link  44 , and the link interface  224  can include a pair of angled flanges  228   a ,  228   b  disposed on opposite sides of a second link  44 . When the link interfaces  222 ,  224  are rotated relative to the housing  102  in response to actuation by the rotary actuator  210 , the angled flanges  226   a ,  226   b ,  228   a ,  228   b  engage the first and second links  44  and thereby rotate the elevator  100  relative to the links  44 . The link interface system  220  (which includes the items shown in  FIG.  14 A ) can rotate the elevator+/−95 degrees from a position that is perpendicular to a longitudinal axis  86  of the links  44 . This equates to a possible rotation of at least 190 degrees when the elevator  100  is rotated through its full rotation. Please note that the link interface system  220  is described in more detail below with reference to  FIG.  14 A . 
       FIG.  8 A  is a center cross-sectional view of an elevator  100  similar to the one shown in  FIG.  7   . The cross-section is generally at the center of the elevator  100  and perpendicular to the axis  80 .  FIG.  8 A  illustrates how the latches  110 ,  120 ,  130 ,  140  engage each other when in the engaged position to distribute the compressive forces caused when hanging the tubular  38  from the elevator  100 . When the tubular  38  (or tubular string  28 ) engages the jaws  140   a ,  140   b  of the latch  140 , compression forces  54 ,  56  are transmitted diagonally down through the stacked latches as indicated by the arrows  54 ,  56  to the housing  102 . This stack of the latches  110 ,  120 ,  130 ,  140  can reduce lateral forces acting on the latches  110 ,  120 ,  130 ,  140  and allows the latches  110 ,  120 ,  130 ,  140  to be a lighter weight design thereby reducing an overall weight of the elevator  100 . As the latches are sequentially rotated into a disengaged position, then the diameter of the opening through the elevator  100  can increase allowing larger tubulars  38  to be handled by the elevator  100 . As the latches  110 ,  120 ,  130 ,  140  are sequentially disengaged, the latches that remain in the engaged position carries the load of the tubular  38  and transmits the load diagonally down through the remaining engaged latches as indicated by the arrows  54 ,  56  to the housing  102 . 
     The central bore  74  of the housing  102  can have a tapered bore with a maximum diameter D 1  and a minimum diameter D 2 . The tapered bore is not a requirement, but the taper can assist in guiding an end of the tubular  38  into the central bore  74 . It should be understood that the central bore  74  may not be tapered, such that diameter D 1  is equal to diameter D 2 . However, it is preferred that the central bore  74  is tapered. A spacer ring  108  can be positioned between the housing  102  and the latches  110 ,  120 ,  130 , and  140  to provide a compression interface between the housing  102  and the latches  110 ,  120 ,  130 , and  140 . The spacer ring  108  can include an inner surface  360 , an outer surface  362 , a top surface  366 , and an engagement surface  364 . The inner surface  360  can be tapered toward the center axis  84  which also guides the tubulars  38  into a variable diameter opening through the elevator  100  created by the latches  110 ,  120 ,  130 , and  140 . The spacer ring  108  transmits the compression force from the latches  110 ,  120 ,  130 , and  140  to the housing  102 . The compression forces  54 ,  56  can be transmitted to the housing  102  through compression sensors  188 ,  189  that can measure the compression force applied to the elevator  100  by the tubular  38 . It should be understood that any number of compression sensors  188 ,  189  can be used as needed to measure the compression force applied by the tubular  38 . 
     This elevator  100 , with the housing in a substantially horizontal orientation, can be configured to support a tubular that weighs up to 1180 metric tons (˜ 1300 short tons), or up to 1134 metric tons (˜ 1250 short tons), or up to 1189 metric tons (˜ 1200 short tons), or up to 907 metric tons (˜ 1000 short tons), or up to 680 metric tons (˜ 750 short tons), or up to 454 metric tons (˜ 500 short tons), or up to 318 metric tons (˜ 350 short tons), or up to 227 metric tons (˜250 short tons). The elevator  100  can be configured to manipulate a tubular  38  between horizontal and vertical orientations with the tubular  38  weighing up to 3000 kg (˜3 short tons). Therefore, when one or more of the latches  110 ,  120 ,  130 ,  140  of the elevator  100  are engaged with a tubular  38  positioned on a horizontally oriented tubular handling system (e.g., system  60 ), the elevator  100  can engage the tubular  38 , hoist the tubular  38  from the horizontal orientation on the handling system (e.g., system  60 ), and rotate with the tubular  38  to a vertical orientation to enable connection of the tubular  38  to the tubular string  28 . The elevator  100  is also configured to manipulate the tubular  38  when it is disconnected from the tubular string  28  from a vertical orientation to a horizontal orientation on the handling system. Seals  370  can seal between the housing  102  and the spacer ring  108  to minimize (or prevent) fluids and debris from entering the space between the housing  102  and the spacer ring  108 . The sensors  188 ,  189  may also incorporate seals that minimize (or prevent) fluids and debris from entering the space between the housing  102  and the spacer ring  108 . It is preferred to minimize fluid and debris from entering this space, thereby reducing possible in accurate readings from the sensors  188 ,  189 . It should be understood that other benefits are possible with sealing this space from the fluids and debris. 
     The elevator  100  can accept tubulars  38  with a maximum diameter that is incrementally less than the diameter D 3  of the opening in the spacer ring  108 , the opening being defined at the intersection of the engagement surface  364  and the inner surface  360 . It should be understood that the inner surface  360  of the spacer ring  108  can be parallel to the tubular  38  instead of being tapered, as shown in  FIG.  8 A . Therefore, the diameter D 3  can be equal to the diameter D 2 . Also, the central bore  74  can have an inner surface that is parallel with the tubular  38  with the diameter D 2  being equal to the diameter D 1 . The box end  39  of the tubular  38  should have enough clearance between the opening of the spacer ring  108  and the tubular  38  to allow ease of movement of the tubular  38  through the opening. Once the box end  39  (not shown in  FIG.  8 A ) is received through the opening of the spacer ring (and thus the opening of the elevator  100 ), the first latch  110  can be rotated from a disengaged position to an engaged position. 
     Each jaw  110   a ,  110   b  of the first latch  110  includes an engagement portion  114 ,  118 , which includes a lateral portion  112 ,  116  and a tapered portion  113 ,  117 . Each jaw  120   a ,  120   b  of the second latch  120  includes an engagement portion  124 ,  128 , which includes a lateral portion  122 ,  126  and a tapered portion  123 ,  127 . Each jaw  130   a ,  130   b  of the third latch  130  includes an engagement portion  134 ,  138 , which includes a lateral portion  132 ,  136  and a tapered portion  133 ,  137 . Each jaw  140   a ,  140   b  of the fourth latch  140  includes an engagement portion  144 ,  148 , which includes a lateral portion  142 ,  146  and a tapered portion  143 ,  147 . The lateral portions of each latch overlap the lateral portions of the other latches that are in an engaged position. The tapered portions of each latch engage the tapered portions of adjacent latches when the latches are in the engaged position, as shown in  FIG.  8 A . 
     Jaws  110   a ,  110   b  can be rotated into position by the actuator  212  that acts on the drive shafts  162 ,  164 , respectively. The jaws  110   a ,  110   b  can include an attachment portion  180 ,  181 , and an engagement portion  114 ,  118 , respectively. The attachment portions  180 ,  181  are not shown in  FIG.  8 A , because they are present in the other half of the elevator  100  not shown in the current cross-sectional view. However, the relative positions of the attachment portions are indicated by the reference numerals  180 ,  181 . The attachment portions  180 ,  181  are the portions of the jaws  110   a ,  110   b  that attach the jaws to the respective drive shafts  162 ,  164 . The engagement portions  114 ,  118  are the portions of the jaws  110   a ,  110   b  that engage the spacer ring  108  when in the engaged position. The lateral portions  112 ,  116  connect the tapered portions  113 ,  117  to the attachment portions  180 ,  181  to form the respective jaws  110   a ,  110   b . The tapered portions  113 ,  117  transfer compression forces  54 ,  56  to the spacer ring  108  through the engagement surface  364 . A bottom surface of the tapered portions  113 ,  117  can be tapered to match the taper of the inner surface  360  of the spacer ring  108 . 
     Jaws  120   a ,  120   b  can be rotated into position by the actuator  214  that acts on the drive shafts  166 ,  168 , respectively. The jaws  120   a ,  120   b  can include an attachment portion  182 ,  183 , and an engagement portion  124 ,  128 , respectively. The attachment portions  182 ,  183  are the portions of the jaws  120   a ,  120   b  that attach the jaws to the respective drive shafts  166 ,  168 . The engagement portions  124 ,  128  are the portions of the jaws  120   a ,  120   b  that engage the engagement portions  114 ,  118  of the first latch  110  when in the engaged position. The lateral portions  122 ,  126  connect the tapered portions  123 ,  127  to the attachment portions  182 ,  183  to form the respective jaws  120   a ,  120   b . The tapered portions  123 ,  127  transfer compression forces  54 ,  56  to the spacer ring  108  through the tapered portions  113 ,  117  and the engagement surface  364  of the spacer ring  108 . A bottom surface of the tapered portions  123 ,  127  can be tapered to facilitate entry of the tubular  38  into the elevator opening. 
     Jaws  130   a ,  130   b  can be rotated into position by the actuator  216  that acts on the drive shafts  172 ,  174 , respectively. The jaws  130   a ,  130   b  can include an attachment portion  184 ,  185 , and an engagement portion  134 ,  138 , respectively. The attachment portions  184 ,  185  are not shown in  FIG.  8 A , because they are present in the other half of the elevator  100  not shown in the current cross-sectional view. However, the relative positions of the attachment portions are indicated by the reference numerals  184 ,  185 . The attachment portions  184 ,  185  are the portions of the jaws  130   a ,  130   b  that attach the jaws to the respective drive shafts  172 ,  174 . The engagement portions  134 ,  138  are the portions of the jaws  130   a ,  130   b  that engage the engagement portions  124 ,  128  of the second latch  120  when in the engaged position. The lateral portions  132 ,  136  connect the tapered portions  133 ,  137  to the attachment portions  184 ,  185  to form the respective jaws  130   a ,  130   b . The tapered portions  133 ,  137  transfer compression forces  54 ,  56  to the spacer ring  108  through tapered portions  113 ,  117 ,  123 ,  127  and the engagement surface  364  of the spacer ring  108 . A bottom surface of the tapered portions  133 ,  137  can be tapered to facilitate entry of the tubular  38  into the elevator opening. 
     Jaws  140   a ,  140   b  can be rotated into position by the actuator  218  that acts on the drive shafts  176 ,  178 , respectively. The jaws  140   a ,  140   b  can include an attachment portion  186 ,  187 , and an engagement portion  144 ,  148 , respectively. The attachment portions  186 ,  187  are the portions of the jaws  140   a ,  140   b  that attach the jaws to the respective drive shafts  176 ,  178 . The engagement portions  144 ,  148  are the portions of the jaws  140   a ,  140   b  that engage the engagement portions  134 ,  138  of the third latch  130  when in the engaged position. The lateral portions  142 ,  146  connect the tapered portions  143 ,  147  to the attachment portions  186 ,  187 , via the joints  149   a ,  149   b  (see  FIG.  9   ), to form the respective jaws  140   a ,  140   b . The tapered portions  143 ,  147  transfer compression forces  54 ,  56  to the spacer ring  108  through tapered portions  113 ,  117 ,  123 ,  127 ,  133 ,  137 , and the engagement surface  364  of the spacer ring  108 . A bottom surface of the tapered portions  143 ,  147  can be tapered to facilitate entry of the tubular  38  into the elevator opening. 
     The tapered portions of each pair of jaws can form a frusticonically shaped portion of the respective latch when the latch is in the engaged position. Therefore, the tapered portions  113 ,  117  can form a frusticonically shaped portion of the latch  110  that engages a frusticonically shaped inner surface  364  of the spacer ring  108 . The tapered portions  123 ,  127  can form a frusticonically shaped portion of the latch  120  that engages the frusticonically shaped portion of the latch  110 . The tapered portions  133 ,  137  can form a frusticonically shaped portion of the latch  130  that engages the frusticonically shaped portion of the latch  120 . The tapered portions  143 ,  147  can form a frusticonically shaped portion of the latch  140  that engages the frusticonically shaped portion of the latch  130 . 
     As can be seen in  FIG.  8 A , the later portions of the jaws can be substantially parallel to each other and can overlap each other when the jaws are in the engaged position. The attachment portions of the jaws can provide the interface between the lateral portions that are at different longitudinal positions along the central axis  84  and pairs of drive shafts that are positioned at the same longitudinal position. For example, the drive shafts  162 ,  166  (see  FIG.  6   ) rotate about the same axis  90  and are therefore at the same longitudinal position along the central axis  84 . The drive shafts  164 ,  168  (see  FIG.  6   ) rotate about the same axis  92  and are therefore at the same longitudinal position along the central axis  84 . In the embodiments of  FIGS.  6 - 8 A , the axes  90  and  92  are at the same longitudinal position along the axis  84 . Similarly, the axes  94  and  96  are at a same longitudinal position along the axis  84 . However, the longitudinal position of the axes  90  and  92  can be different than the longitudinal position of the axes  94  and  96 . 
     Additionally, the axes  90  and  92  are positioned on opposite sides of the central axis  84  and can be spaced away from the central axis  84  by substantially a same first distance. However, in other embodiments, a distance between the axis  90  and the central axis  84  can be different than a distance between the axis  92  and the central axis  84 . The axes  94  and  96  are positioned on opposite sides of the central axis  84  and can be spaced away from the central axis  84  by substantially a same second distance. However, in other embodiments, the distance between the axis  94  and the central axis  84  can be different than the distance between the axis  96  and the central axis  84 . The same first distance from the axes  90  or  92  to the central axis  84  is preferably less than the same second distance from the axes  94  or  96  to the central axis  84 . 
     As stated above, the central bore  74  of the housing  102  can have a tapered bore with a maximum diameter D 1  and a minimum diameter D 2 . The spacer ring  108  can have a minimum diameter D 3 , which defines a minimum diameter of the opening  88  through the latches and defines the maximum diameter of a tubular  38  that can be received into the elevator  100  when all latches  110 ,  120 ,  130 ,  140  are in the disengaged position. When the latch  110  is in the engaged position, the minimum diameter of the opening  88  through the latches is diameter D 4 . Diameter D 4  defines the maximum diameter of a tubular  38  that can be received into the elevator  100  when the latch  110  is engaged and the latches  120 ,  130 ,  140  are disengaged. Diameter D 4  also defines the minimum diameter D 9  of a box end  39  that can be retained by the latch  110  when the latch  110  is engaged. When the latch  120  is in the engaged position, the minimum diameter of the opening  88  through the latches is diameter D 5 . Diameter D 5  defines the maximum diameter of a tubular  38  that can be received into the elevator  100  when the latches  110 ,  120  are engaged and the latches  130 ,  140  are disengaged. Diameter D 5  also defines the minimum diameter D 9  of a box end  39  that can be retained by the latch  120  when the latch  120  is engaged. When the latch  130  is in the engaged position, the minimum diameter of the opening  88  through the latches is diameter D 6 . Diameter D 6  defines the maximum diameter of a tubular  38  that can be received into the elevator  100  when the latches  110 ,  120  are engaged and the latches  130 ,  140  are disengaged. Diameter D 6  also defines the minimum diameter D 9  of a box end  39  that can be retained by the latch  130  when the latch  130  is engaged. 
     When the latch  140  is in the engaged position, the minimum diameter of the opening  88  through the latches is diameter D 7 . Diameter D 7  defines the minimum diameter D 9  of a box end  39  that can be retained by the latch  140 , and thus the elevator  100 , when the latch  140  is engaged. In each configuration of the latches  110 ,  120 ,  130 ,  140 , the box end  39  of the tubular  38  should be larger than the minimum diameter of the opening  88  and the radially reduced portion  37  of the tubular  38  should be smaller than the minimum diameter of the opening. For example, when all latches  110 ,  120 ,  130 ,  140  are in the engaged position, the diameter D 9  of the box end  39  is larger than the diameter D 7 , while the diameter D 10  is smaller than the diameter D 7 . Therefore, when the latch  140  is disengaged, the tubular  38  can be inserted through the opening  88  of the elevator  100  since the diameter D 9  of the box end  39  is smaller than diameter D 6  of engaged latch  130 . When the box end  39  is passed through the elevator  100 , the latch  140  can then be engaged to decrease the diameter of the opening  88  from diameter D 6  to diameter D 7 , which will prevent the box end  39  from passing back through the elevator  100 , since the diameter D 7  is smaller than the diameter D 9 . This operation would perform similarly for larger and larger diameter tubulars  38  when the appropriate latches are engaged with the others disengaged, depending upon the desired configuration. 
       FIG.  8 B  is a more detailed view of the region  8 B in  FIG.  8 A .  FIG.  8 B  provides a better view of portions of jaws  130   b ,  140   b  in the engaged position. Each jaw of the elevator  100  includes similar portions and surfaces as those shown for the jaw  140   b . Jaw  140   b  includes an attachment portion  187  that connects the engagement portion  148  to its respective drive shaft. The attachment portion  187  can be mechanically coupled to the engagement portion  148  by the mechanical joint  149   b . The mechanical joint  149   b  allows some mechanical play between the engagement portion  148  and the attachment portion  187  such that forces applied to the latch  140  when the latch  140  is engaged with a tubular are prevented (or at least minimized) from being transmitted through the engagement portion  148  to the attachment portion  187  and to the housing  102  through the respective drive shaft. This can ensure that substantially all of the forces applied by the tubular  38  to the elevator  100  are transmitted to the spacer ring  108  and to the compression sensors  188 ,  189  (or circular weight sensor  480 , see  FIGS.  25 - 28 B ). Similar joints can be included in each of the jaws  110 ,  120 ,  130 ,  140  of the elevator  100 . The engagement portion  148  can include a lateral portion  146  and a tapered portion  147 , where the lateral portion  146  couples the attachment portion  187  to the tapered portion  147 , via the joint  149   b . The tapered portion  147  is indicated as the portion of the jaw  140   b  bounded by the arrows extending from a distal surface  248  to a point where the tapered portion  147  transitions to the lateral portion  146 . The lateral portion  146  is indicated as the portion of the jaw  140   b  bounded by the arrows extending from the transition point between the tapered portion  147  and the lateral portion  146  to a transition point (i.e., the joint  149   b ) between the lateral portion  146  and the attachment portion  187  portion. 
     As stated above, the tapered portions of each pair of jaws can form a frusticonically shaped portion of the respective latch when the latch is in the engaged position.  FIG.  8 B  shows the portions for a single jaw  130   b  of the jaw pair  130   a ,  130   b  that makes up the latch  130 . The tapered portion  137  of the jaw  130   b  can form a circumferential part of the frusticonically shaped portion of the latch  130 .  FIG.  8 B  also shows the portions for a single jaw  140   b  of the jaw pair  140   a ,  140   b  that makes up the latch  140 . The tapered portion  147  of the jaw  140   b  can form a circumferential part of the frusticonically shaped portion of the latch  140 . The tapered portion  147  engages the tapered portion  137  when the latches  140 ,  130  are in the engaged position. 
     The jaw  140   b  includes a top surface  240  of the lateral portion  146  that transitions to a concave inner surface  244  of the tapered portion  147  at a transition surface  242 . The inner surface  244  transitions to a distal surface  248  at an engagement edge  246 . The concave inner surface  244  tapers toward the central axis  84  from the transition surface  242  to the engagement edge  246 . The concave inner surfaces  244  and engagement edges  246  of each jaw are configured to engage the tubular  38  (e.g., box end  39 ) and can allow for various tubular diameters within a range between the minimum diameters of the adjacent latches without reconfiguring the latches. The concave inner surface  244  can allow for varied manufacturing tolerances of the tubulars  38 . When the box end  39  engages any point along the concave inner surface  244 , the weight of the tubular is transmitted through the engagement portions of the engaged latches to the spacer ring  108 . The distal surface  248  is also concave shaped and forms a tapered surface that is tapered at a different angle from the central axis  84  than the concave surface  244 . 
     The distal surface  248  can taper away from the central axis  84  from the engagement edge  246  to a bottom edge  250 . The distal surface  248  transitions to a convex shaped outer surface  252  at the bottom edge  250 . The outer surface  252  is configured to complimentarily engage a concave inner surface  244  of the jaw  130   b . The outer surface  252  transitions to a bottom surface  256  of the lateral portion  146  at a transition surface  254 . In this embodiment, the lateral portions  146 ,  136  of the jaws  140   b ,  130   b , respectively, are substantially parallel to each other and longitudinally spaced apart. The longitudinal space between the lateral portions  146 ,  136  directs the compression forces  56  to be transmitted through the tapered portions  147 ,  137  with minimal compression forces, that are applied by an engaged tubular to the elevator  100 , to be directed through the lateral portions  146 ,  136 , through the joints  149   b ,  139   b , through the attachment portions  187 ,  185 , respectively, and to the housing through the respective drive shafts. The joints  149   b ,  139   b  allow mechanical play between the lateral portions  146 ,  136  and the engagement portions  148 ,  138  to prevent (or at least minimize) transmission of the compression forces to the housing through the attachment portions  148 ,  138 . However, the lateral portions  146 ,  136  can engage each other in other embodiments, thereby allowing more of the compression forces  56  to be transmitted through the lateral portions  146 ,  136 . 
       FIG.  8 C  is a detailed cross-sectional view of an alternate configuration of the elevator  100  when viewing the region  8 B in  FIG.  8 A . The jaws  140   b  and  130   b  are similar to those shown in  FIG.  8 B , except that the lateral portions may be thicker and the tapered portions  147 ,  137  can have additional engagement surfaces. The top surface  240  of the lateral portion  146  transitions to the concave shaped inner surface  244  of the tapered portion  147  at the transition surface  242  which can be similar to the transition surface  242  of the jaw  140   b  shown in  FIG.  8 B . However, the transition surface  242  of the jaw  130   b  is noticeably different than the transition surface  242  of the jaw  130   b  in  FIG.  8 B . The transition surface  254  of the jaw  140   b  forms a circumferential recess in the bottom of the jaw  140   b . The transition surface  242  of the jaw  130   b  forms a circumferential ridge that engages the circumferential recess  254  of the jaw  140   b . The engagement of the jaws  140   b  and  130   b  can provide additional engagement surfaces between the adjacent jaws  140   b  and  130   b . It should be noted that the transition surface  254  of the jaw  110   b  can include a circumferential recess that engages a circumferential ridge on the spacer ring  108  or the transition surface  254  of the jaw  110   b  can be formed without a circumferential recess. Again, the lateral portions of the jaws can be substantially parallel to each other and longitudinally spaced apart similar to the configuration shown in  FIG.  8 B . However, the lateral portions can alternatively engage each other in addition to the engagement of the tapered portions. 
       FIG.  8 D  is similar to the elevator  100  shown in  FIG.  8 A , except that the latches  110 ,  120  can have a different configuration than those shown in  FIG.  8 A . The description regarding  FIG.  8 A  above is applicable to  FIG.  8 D , except for the specific structural differences of the latches  110 ,  120 . The latch  110  in  FIG.  8 A  can be used to engage box ends  39  of tubulars  38 , where the latch  110  forms a frustoconical shaped engagement portion that has tapered inner and outer surfaces  244 ,  252 . However, with flanged casing tubulars  38 , the top end of the tubular  38  can include a right-angle flange that is not tapered (or at least has a significantly reduced taper compared to drilling tubulars  38 ) relative to the body of the tubular  38 . Therefore, the latch  110  shown in  FIG.  8 D  can be used to engage a right-angle flange of a casing tubular  38 . Please note that the surface  242  of the jaw  110   b  is shown as a substantially right-angle transition between the top surface of the jaw  110   b  and the inner surface  244 . When the latch  110  is in the engaged position it can form a cylindrically shaped engagement portion with the inner surfaces  244  of the jaws  110   a ,  110   b  forming a cylindrical surface that is generally parallel with a tubular  38  when the tubular  38  is engaged with the elevator  100 . An outer surface  252  of the engagement portion can be tapered as shown to interface with the inclined inner surface  364  of the spacer ring  108 . The surface  254  of the jaw  110   b  transitions the outer surface  252  to the lower surface of the jaw  110   b . The latch  110  can be used to engage a casing tubular  38  with a right-angle flange, and the latches  120 ,  130 ,  140  can be configured to engage tubulars  38  with a box end  39  having a tapered surface extending between the tubular  38  body and the box end  39 . The latch  120  can be modified to accommodate the different structural configuration of the latch  110  by having surfaces  254 ,  252  of the jaws  120   a ,  120   b  complimentarily formed to engage with surfaces  242 ,  244 , respectively, of jaws  110   a ,  110   b . It should be understood that the other latches  120 ,  130 ,  140  can also be configured to accommodate tubulars  38  with right angled flanges at one end. The latches  110 ,  120 ,  130 ,  140  can operate as described above by being selectively rotated into and out of the engagement position. These latches  110 ,  120 ,  130 ,  140  can be configured with the engagement ridges and recesses as indicated and described regarding  FIG.  8 C  with latch  110  configured to have right angle engagement surfaces without the ridge  242  and the latch  120  configured without the recess  254 . 
       FIG.  9    is a top view of an elevator similar to the elevator in  FIG.  7   , except that  FIG.  9    shows only the top two latches  130 ,  140  in an engaged position. The lower latches  110 ,  120  are removed for clarity, except that a few references that are made to latches  110 ,  120 . The discussion regarding latches  130 ,  140  can also apply similarly to latches  110 ,  120 . A portion of the housing  102  is shown on both sides of  FIG.  9    which indicates rotational attachment points of the latches  130 ,  140  to the housing  102 . 
     The latch  130  comprises jaws  130   a ,  130   b , with each jaw  130   a ,  130   b  fixedly attached to a drive shaft  172 ,  174 , respectively, which is rotationally attached to the housing  102 . The drive shafts  172 ,  174  can be rotated  76 ,  78  about axes  94 ,  96  by the coupling  236  which can be coupled to a rotary actuator to rotate the drive shafts  172 ,  174  together, but in opposite directions, as described above. It should be understood that the drive shafts  172 ,  174  can rotate independently of the drive shafts  176 ,  178 . The drive shafts  172 ,  174  each extend through a wall  392  of the housing  102  where seals  382 ,  384 , respectively, minimize (or prevent) fluids and/or debris from entering the chamber  106  within the housing  102  where the actuators, couplings and controllers can be contained. Jaw  130   a  includes an attachment portion  184 , a joint  139   a , a lateral portion  132 , and a tapered portion  133 . Jaw  130   b  includes an attachment portion  185 , a joint  139   b , a lateral portion  136 , and a tapered portion  137 . When the latch  130  is rotated to the engaged position, the tapered portions  133 ,  137  form a frusticonically shaped portion, with each of the tapered portions  133 ,  137  forming a circumferential portion of the frusticonically shaped portion with a gap  264  formed between the portions  133 ,  137 . This gap  264  can have a width W 3 , which can be approximately 10 mm. It should be understood that the width W 3  can be near zero at times if the tapered portions  133 ,  137  abut each other during operation of the elevator  100 . However, the gap  264  can provide clearances during rotation of the latch  130  between engaged and disengaged positions and clearances to allow mud and other fluids to drain through the elevator  100  when the latches are engaged with a tubular  38 . The gap  264  can lie in a plane  274  that bisects the frusticonically shaped portion of the latch  130 . The plane  274  can be defined by both axes  80  and  84 . It should be understood that the plane  274  that bisects the frusticonically shaped portion of the latch  130  can be parallel to the axis  80  and angled relative to the axis  84 . This can result in an angled face of the tapered portions  133 ,  137  relative to the axis  84 . It should also be understood that the gap  264  can have a width W 3  that increases or decreases along the longitudinal length of the gap  274 . 
     The latch  140  comprises jaws  140   a ,  140   b , with each jaw  140   a ,  140   b  fixedly attached to a drive shaft  176 ,  178 , respectively, which is rotationally attached to the housing  102 . The drive shafts  176 ,  178  are rotated  76 ,  78  about axes  94 ,  96  by the coupling  238  which can be coupled to a rotary actuator to rotate the drive shafts  176 ,  178  together, but in opposite directions, as described above. The drive shafts  176 ,  178  each extend through a wall  394  of the housing  102  where seals  386 ,  388 , respectively, minimize (or prevent) fluids and/or debris from entering the chamber  106  within the housing  102  where the actuators, couplings and controllers can be contained. Jaw  140   a  includes an attachment portion  186 , a joint  149   a , a lateral portion  142 , and a tapered portion  143 . Jaw  140   b  includes an attachment portion  187 , a joint  149   b , a lateral portion  146 , and a tapered portion  147 . When the latch  140  is rotated to the engaged position, the tapered portions  143 ,  147  form a frusticonically shaped portion, with each of the tapered portions  143 ,  147  forming a circumferential portion of the frusticonically shaped portion with a gap  266  formed between the portions  143 ,  147 . This gap  266  can have a width W 4 , which can be approximately 10 mm. It should be understood that the width W 4  can be near zero at times if the tapered portions  144 ,  148  abut each other during operation of the elevator  100 . However, the gap  266  can also provide clearances during rotation of the latch  140  between engaged and disengaged positions. The gap  266  can lie in a plane  276  that bisects the frusticonically shaped portion of the latch  140 . The plane  276  can be defined by both axes  80  and  84 . It should be understood that the plane  276  that bisects the frusticonically shaped portion of the latch  140  can be parallel to the axis  80  and angled relative to the axis  84 . This can result in an angled face of the tapered portions  143 ,  147  relative to the axis  84 . It should also be understood that the gap  266  can have a width W 4  that increases or decreases along the longitudinal length of the gap  276 . 
     It should be understood that the latches  110 ,  120 , which are not shown, may include gaps  260 ,  262  with widths W 1 , W 2 , respectively, and can lie in planes  270 ,  272 , respectively. The widths W 1 , W 2  can be approximately 10 mm. It should be understood that the widths W 1  or W 2  can be near zero at times if the tapered portions  113 ,  117  or  123 ,  127  abut each other during operation of the elevator  100 . However, the gaps  260  and  262  can provide clearances during rotation of the respective latches  110 ,  120  between engaged and disengaged positions and clearances to allow mud and other fluids to drain through the elevator  100  when the latches are engaged with a tubular  38 . The planes  270 ,  272  can be defined by both axes  80 ,  84  or they can be parallel to the axis  80  and angled relative to the axis  84 . This can result in an angled face of the tapered portions  113 ,  117  and  123 ,  127  relative to the axis  84 . It should also be understood that the gap  260  can have a width W 1  that increases or decreases along the longitudinal length of the plane  270 . It should also be understood that the gap  262  can have a width W 2  that increases or decreases along the longitudinal length of the plane  272 . 
       FIG.  10    is a cross-sectional view of the elevator  100  of  FIG.  9    with the latches  130 ,  140  being in engaged positions. As can be seen, the tapered portions  143 ,  147  of the latch  140  engage the tapered portions  133 ,  137  of the latch  130  when these latches  130 ,  140  are in the engaged positions. The tapered portions  133 ,  137  form a frusticonically shaped portion of the latch  130  with a gap  264  having a width W 3 . The tapered portions  143 ,  147  form a frusticonically shaped portion of the latch  140  with a gap  266  having a width W 4 . In this configuration, the gaps  264 ,  266  are aligned with each other and lie in a respective plane  274 ,  276 , which are both defined by axes  80 ,  84 . The frusticonically shaped portion of the latch  130  has a minimum diameter D 6 . The frusticonically shaped portion of the latch  140  has a minimum diameter D 7 . 
       FIG.  11    is a cut-away perspective view of an elevator  100  with four latches  110 ,  120 ,  130 ,  140  operated by rotary actuators  212 ,  214 ,  216 ,  218 , respectively. The actuator  212  has been operated to rotate the latch jaws  110   a ,  110   b  into an engaged position. Therefore, the actuator  212  rotated, via the coupling  232 , the drive shafts  162 ,  164  thereby rotating the jaws  110   a ,  110   b  into the engaged position. The tapered portions  113 ,  117  form the frusticonically shaped portion of the latch  110 . The coupling  232  can include a drive gear  300  fixedly connected to a rotor of the rotary actuator, the gear  300  can be coupled to a gear  302  that couples to a gear  304 . The gear  304  can be fixedly attached to the drive shaft  164  which is rotated when the gear  304  is rotated. The gear  304  can also be coupled to a lever arm  308  via a link  306 . The lever arm  308  can be fixedly attached to the drive shaft  162 . When the gear  304  is rotated in one direction, the link  306  operates to move the lever arm  308  such that is rotates the drive shaft  162  in an opposite direction. 
     Couplings  234 ,  236 ,  238  that couple the other rotary actuators  214 ,  216 ,  218  to the latches  120 ,  130 , and  140 , respectively, can be similar to the coupling  232 , or they can be different as needed to rotate the jaws in each jaw pair  120   a, b ,  130   a,b ,  140   a,b  in opposite directions to rotate the jaw pairs between engaged and disengaged positions. The jaw pairs  120   a, b ,  130   a,b ,  140   a,b  are shown in a disengaged position in  FIG.  11   . It can also be seen in  FIG.  11   , how the extended circumferential ridge  242  on one jaw (e.g.,  130   b ) engages a circumferential recess  254  on an adjacent jaw (e.g.,  140   b ). 
     Additionally, the rotary actuators  212 ,  214 ,  216 ,  218  can include sensors  192 ,  194 ,  196 ,  198  attached the respective actuator that provides the rotational position of the rotary actuator at any time. Therefore, by sending the positional information to a controller (e.g., 50) the position of the latches  110 ,  120 ,  130 ,  140  can be determined with a high degree of certainty. Because the drive shafts that drive the latches are sealed to the housing  102  where they extend through a wall of the housing  102 , then the position sensors  192 ,  194 ,  196 ,  198  are protected from the harsh fluids and debris present outside the sealed chamber  106  of the housing  102 . 
     The elevator  100  of  FIG.  11    is similar to the elevator  100  in  FIG.  6   , except that the gaps in the frusticonically shaped portions of the latches  110 ,  120 ,  130 ,  140 , are not aligned with gaps in the frusticonically shaped portions of adjacent latches. As can be seen, the gap when the latch  140  is engaged between the frusticonically shaped portions  143 ,  147  will be circumferentially offset from the gap between the frusticonically shaped portions  133 ,  137  in an engaged position. The other latches  110 ,  120  have respective gaps  160 ,  162  which can also be circumferentially offset from other gaps of the latches. 
       FIG.  12    is a top view of an elevator  100  similar to the elevator in  FIG.  11    for handling tubulars, the latches  130 ,  140  being in an engaged position. The lower latches  110 ,  120  are removed for clarity, except that a few references that are made to latches  110 ,  120 . The discussion regarding latches  130 ,  140  can also apply similarly to latches  110 ,  120 . A portion of the housing  102  is shown on both sides of  FIG.  12    which indicates rotational attachment points of the latches  130 ,  140  to the housing  102 . 
     The latch  130  comprises jaws  130   a ,  130   b , with each jaw  130   a ,  130   b  fixedly attached to a drive shaft  172 ,  174 , respectively, which is rotationally attached to the housing  102 . The drive shafts  172 ,  174  can be rotated  76 ,  78  about axes  94 ,  96  by the coupling  236  which can be coupled to a rotary actuator to rotate the drive shafts  172 ,  174  together, but in opposite directions, as described above. It should be understood that the drive shafts  172 ,  174  can rotate independently of the drive shafts  176 ,  178 . The drive shafts  172 ,  174  each extend through a wall  392  of the housing  102  where seals  382 ,  384 , respectively, minimize (or prevent) fluids and/or debris from entering the chamber  106  within the housing  102  where the actuators, couplings and controllers can be contained. Jaw  130   a  includes an attachment portion  184 , a joint  139   a , a lateral portion  132 , and a tapered portion  133 . Jaw  130   b  includes an attachment portion  185 , a joint  139   b , a lateral portion  136 , and a tapered portion  137 . When the latch  130  is rotated to the engaged position, the tapered portions  133 ,  137  form a frusticonically shaped portion, with each of the tapered portions  133 ,  137  forming a circumferential portion of the frusticonically shaped portion with a gap  264  formed between the portions  133 ,  137 . This gap  264  can have a width W 3 . It should be understood that the width W 3  can be near zero at times if the tapered portions  133 ,  137  abut each other during operation of the elevator  100 . However, the gap  264  can also provide clearances during rotation of the latch  130  between engaged and disengaged positions. The gap  264  can lie in a plane  274  that bisects the frusticonically shaped portion of the latch  130 . The plane  274  can be parallel to the axis  84  and angled relative to the axis  80  by a circumferential offset  286 . It should be understood that the plane  274  that bisects the frusticonically shaped portion of the latch  130  can be angled relative to the axis  80  and angled relative to the axis  84 . This can result in an angled face of the tapered portions  133 ,  137  relative to the axis  84  and circumferentially offset from the axis  80 . It should also be understood that the gap  264  can have a width W 3  that increases or decreases along the longitudinal length of the gap  274 . 
     The latch  140  comprises jaws  140   a ,  140   b , with each jaw  140   a ,  140   b  fixedly attached to a drive shaft  176 ,  178 , respectively, which is rotationally attached to the housing  102 . The drive shafts  176 ,  178  are rotated  76 ,  78  about axes  94 ,  96  by the coupling  238  which can be coupled to a rotary actuator to rotate the drive shafts  176 ,  178  together, but in opposite directions, as described above. The drive shafts  176 ,  178  each extend through a wall  394  of the housing  102  where seals  386 ,  388 , respectively, minimize (or prevent) fluids and/or debris from entering the chamber  106  within the housing  102  where the actuators, couplings and controllers can be contained. Jaw  140   a  includes an attachment portion  186 , a joint  149   a , a lateral portion  142 , and a tapered portion  143 . Jaw  140   b  includes an attachment portion  187 , a joint  149   b , a lateral portion  146 , and a tapered portion  147 . When the latch  140  is rotated to the engaged position, the tapered portions  143 ,  147  form a frusticonically shaped portion, with each of the tapered portions  143 ,  147  forming a circumferential portion of the frusticonically shaped portion with a gap  266  formed between the portions  143 ,  147 . This gap  266  can have a width W 4 . It should be understood that the width W 4  can be near zero at times if the tapered portions  144 ,  148  abut each other during operation of the elevator  100 . However, the gap  266  can also provide clearances during rotation of the latch  140  between engaged and disengaged positions. The gap  266  can lie in a plane  276  that bisects the frusticonically shaped portion of the latch  140 . The plane  276  can be parallel to the axis  84  and angled relative to the axis  80  by a circumferential offset  288 . It should be understood that the plane  276  that bisects the frusticonically shaped portion of the latch  140  can be angled relative to the axis  80  and angled relative to the axis  84 . This can result in an angled face of the tapered portions  143 ,  147  relative to the axis  84  and circumferentially offset from the axis  80 . It should also be understood that the gap  266  can have a width W 4  that increases or decreases along the longitudinal length of the gap  276 . 
     It should be understood that the latches  110 ,  120 , which are not shown, may include gaps  260 ,  262  with widths W 1 , W 2 , respectively, and can lie in planes  270 ,  272 , respectively. The planes  270 ,  272  can be parallel to the axis  84  and angled relative to the axis  80  by a circumferential offset  286 ,  288 , respectively, or the planes  270 ,  272  can be angled relative to the axis  80  and angled relative to the axis  84 . This can result in an angled face of the tapered portions  113 ,  117  and  123 ,  127  relative to the axis  84  and circumferentially offset from the axis  80 . It should also be understood that the gap  260  can have a width W 1  that increases or decreases along the longitudinal length of the plane  270 . It should also be understood that the gap  262  can have a width W 2  that increases or decreases along the longitudinal length of the plane  272 . 
       FIG.  13    is a cross-sectional view of the elevator  100  of  FIG.  9    with the latches  130 ,  140  being in engaged positions. As can be seen, the tapered portions  143 ,  147  of the latch  140  engage the tapered portions  133 ,  137  of the latch  130  when these latches  130 ,  140  are in the engaged positions. The tapered portions  133 ,  137  form a frusticonically shaped portion of the latch  130  with a gap  264  having a width W 3 . The tapered portions  143 ,  147  form a frusticonically shaped portion of the latch  140  with a gap  266  having a width W 4 . In this configuration, the gaps  264 ,  266  are circumferentially offset from each other. The frusticonically shaped portion of the latch  130  has a minimum diameter D 6 . The frusticonically shaped portion of the latch  140  has a minimum diameter D 7 . 
     The jaws  130   a ,  130   b ,  140   a ,  140   b  are configured similar to the jaws  130   b ,  140   b  in the cross-sectional view of  FIG.  8 C  with the circumferential recess  242  of jaws  140   a ,  140   b  engaging the circumferential ridge  254  of jaws  130   a ,  130   b . The configuration of the jaws in  FIG.  13    also includes a minimal gap (if any at all) between the lateral portions  142 ,  132 , and between the lateral portions  146 ,  136 . However, there can be a gap between the lateral portions if desired. 
     Also, the configuration of the jaws  130   a ,  130   b ,  140   a ,  140   b  in  FIG.  13    illustrate that the attachment portions  184  (not shown) and  186  are parallel to each other and generally within a same plane, and that the attachment portions  185  (not shown) and  187  are parallel to each other and generally within a same plane. At a transition between the attachment portions and the lateral portions, the laws transition from a thicker attachment portion to a narrower lateral portion that allows adjacent lateral portions to overlap each other, as where the attachment portions  184 ,  186  and the attachment portions  185  and  187  do not overlap each other. 
     It should be understood that each pair of jaws,  110   a - b ,  120   a - b ,  130   a - b ,  140   a - b  can have a male/female mating feature with the male mating feature being on one of the jaws in the jaw pair and the female mating feature being on the other one of the jaws in the jaw pair. The male mating feature may engage the female mating feature when the jaw pair  110   a - b ,  120   a - b ,  130   a - b ,  140   a - b  is in the engaged position. The engagement of the male mating feature with the female mating feature can provide additional resistance to the jaw pair being pushed apart when a tubular  38  is being held by the elevator  100 . For example, the male mating feature may be a bolt and the female mating feature may be a hole, with the bolt engaging the hole when the jaw pair is in the engaged (or closed) position. Additionally, the male mating feature may be a ridge and the female mating feature may be a groove, with the ridge engaging the groove when the jaw pair is in the engaged (or closed) position. 
       FIG.  14 A  is a cut-away perspective view of a link interface  220  of an elevator  100  for handling tubulars  38  with other components of the elevator removed for clarity. The link interface system  220  is used to rotate the housing  102  of the elevator  100  relative to the pair of links  44 , which include a link axis  86 . The link interface system  220  can include a rotary actuator  210  that includes a body  208  and drive shafts  160 ,  170 . The drive shafts  160 ,  170  can be coupled to respective link interfaces  222 ,  224  via the coupling  230 . Each of the link interfaces  222 ,  224  can be configured to retain one of the links  44  in a fixed azimuthal relationship with the respective link interface  222 ,  224  relative to the axis  80 . 
     The link interface  222  can include angled flanges  226   a ,  226   b  that straddle the respective link  44  to prevent any substantially rotational movement between the link interface  222  and the respective link  44 . Therefore, the link interface  222  is rotationally fixed at the azimuthal position of the link axis  86  relative to the axis  80 , even though some minor rotation between the link interface  222  and the respective link  44  can occur. The engagement of the angled flanges  226   a ,  226   b  with the respective link  44  can cause the housing  102  to be rotated relative to the axis  80 . 
     The link interface  224  can include angled flanges  228   a ,  228   b  that straddle the respective link  44  to prevent any substantially rotational movement between the link interface  224  and the respective link  44 . Therefore, the link interface  224  is rotationally fixed at the azimuthal position of the link axis  86  relative to the axis  80 , even though some minor rotation between the link interface  224  and the respective link  44  can occur. The engagement of the angled flanges  228   a ,  228   b  with the respective link  44  can cause the housing  102  to be rotated relative to the axis  80 . The link interfaces  222 ,  224  are configured to rotate together to act on each link  44  of the pair of links  44  that couple the elevator  100  to a top drive  42  (or other hoisting mechanism) to rotate the housing  102  relative to the links  44 . 
     The drive shaft  160  can be coupled to the link interface  222  via the drive shaft interface  341  and gear  342  that are fixed to the drive shaft  160 . The gear  342  can be coupled to a gear  344  that is rotationally fixed to a gear  346  via shaft  349 . The shaft  349  can be extended through a wall of the housing  102  and sealed at the wall to allow the rotary actuator  210  and the sensors  190 ,  340  to be disposed in a sealed chamber  106  to separate them from the harsh environment of the latches. The gears  344  and  346  can be connected to a position sensor  340  to can detect the rotation applied to the link interface  222  and send that position data to a controller for determining the azimuthal orientation of the housing  102  relative to the links  44 . Alternatively, or in addition to, a position sensor  190  can be coupled to the drive shaft  160  to determine and report a rotational position of the drive shaft  160 , which the controller (e.g., 50) can use to determine the orientation of the housing  102  relative to the links  44 . The gear  346  can be coupled to a gear  348  that is rotationally fixed to the link interface  222 . Therefore, rotating the drive shaft  160 , causes the gear  348  to rotate, which causes the link interface  222  to rotate relative to the housing  102 , and thereby rotates the housing  102  relative to the link axis  86 . The direction of rotation of the drive shaft  160  determines the direction of rotation of the housing  102  relative to the link axis  86  due to the coupling  230 . 
     The drive shaft  170  can be coupled to the link interface  224  via the drive shaft interface  351  and gear  352  that are fixed to the drive shaft  170 . The gear  352  can be coupled to a gear  354  that is rotationally fixed to a gear  356  via shaft  359 . The shaft  359  can be extended through a wall of the housing  102  and sealed at the wall to allow the rotary actuator  210  and the sensors  190 ,  340  to be disposed in a sealed chamber  106  to separate them from the harsh environment of the latches. The gear  356  can be coupled to a gear  358  that is rotationally fixed to the link interface  224 . Therefore, rotating the drive shaft  170 , causes the gear  358  to rotate, which causes the link interface  224  to rotate relative to the housing  102 , and thereby rotates the housing  102  relative to the link axis  86 . The direction of rotation of the drive shaft  170  determines the direction of rotation of the housing  102  relative to the link axis  86  due to the coupling  230 . Since the rotation of the drive shafts  160  and  170  are the same, then the gears  348  and  358  rotate the link interfaces  222 ,  224  in the same direction. 
       FIG.  14 B  is a representative perspective view of a link interface  222 , which is one of a pair of link interfaces  222 ,  224 . The pair of link interfaces  222 ,  224  can engage the pair of links  44  to allow the elevator to be tilted relative to the links  44 . The link interface  222  is configured to support various diameters of a link  44 . By extending or retracting the angled flanges  226   a ,  226   b  (see arrows  296   a ,  296   b , respectively), the clearance L 2  can be adjusted to accommodate links  44  of various diameters. As shown in  FIG.  7   , the link  44  can engage the link retainer  400  at the end of the link  44 . The angled flanges  226   a ,  226   b  can straddle a portion of the link  44  that is spaced away from the end of the link  44 . This portion has a diameter that can vary between different links  44 . By adjusting the clearance L 2 , the angled flanges  226   a ,  226   b  can snug up against the link  44  to minimize play between the link interface  220  and the link  44 . 
     Each of the angled flanges  226   a ,  226   b  can include a recess  294   a ,  294   b , respectively into which a portion of the body  290  can be inserted. The angled flanges  226   a ,  226   b  can be secured to the body  290  by tightening the fasteners  292 , which can prevent moving (arrows  296   a ,  296   b ) the angled flanges  226   a ,  226   b  relative to the body  290 . To reduce the clearance L 2 , the fasteners  292  can be loosened allowing the angled flanges  226   a ,  226   b  to be extended away from the body  290 . Since the angled flanges  226   a ,  226   b  are angled toward each other, the extension will reduce the clearance L 2  between the angled flanges  226   a ,  226   b . To enlarge the clearance L 2 , the fasteners  292  can be loosened allowing the angled flanges  226   a ,  226   b  to be retracted toward the body  290 . Since the angled flanges  226   a ,  226   b  are angled toward each other, the retraction will enlarge the clearance L 2  between the angled flanges  226   a ,  226   b . Similarly, the link interface  224  can also include moveable angled flanges  226   a ,  226   b ,  228   a ,  228   b . As can be seen, the link interfaces  222 ,  224  can include moveable angled flanges  226   a ,  226   b ,  228   a ,  228   b , respectively, as shown in  FIG.  14 B , or the link interfaces  222 ,  224  can include angled flanges  226   a ,  226   b ,  228   a ,  228   b , respectively, that are integral to the link interfaces  222 ,  224 , as shown in  FIG.  14 A . 
       FIG.  15    shows the rotational movement of the housing  102  (and thus the elevator  100 ) relative to the link axis  86  (and thus the links  44 ). The central axis  84  of the housing  102  can be rotated counterclockwise about axis  80  relative to the link axis  86  by a rotational angle A 2  and rotated clockwise about axis  80  relative to the link axis  86  by a rotational angle A 3 . A 2  can be expressed in—(negative) degrees such a—102 degrees while A 3  can be expressed in +(positive) degrees such as +102 degrees. 
     The angle A 2  can be in the range of “0” degrees to −95 degrees. The angle A 3  can be in the range of “0” degrees to +102 degrees. Therefore, the arc A 1  can be in the range of 204 degrees (i.e., from −102 degrees to +102 degrees). Therefore, the housing  102  can rotate between −102 degrees and +102 degrees about the axis  80  relative to the link axis  86 . The housing  102  can rotate+/−4 degrees, +/−8 degrees, +/−12 degrees, +/−16 degrees, +/−20 degrees, +/−24 degrees, +/−28 degrees, +/−32 degrees, +/−36 degrees, +/−40 degrees, +/−44 degrees, +/−48 degrees, +/−52 degrees, +/−56 degrees, +/−60 degrees, +/−64 degrees, +/−68 degrees, +/−72 degrees, +/−76 degrees, +/−80 degrees, +/−84 degrees, +/−88 degrees, +/−92 degrees, +/−95 degrees, +/−96 degrees, +/−100 degrees, and +/−102 degrees. 
       FIG.  16    shows a detailed cross-sectional perspective view of an elevator with latches generally configured as the latches  110 ,  120 ,  130 ,  140  in  FIG.  11    with the extended ridges and recesses for engaging adjacent latches, and the rotationally offset gaps between adjacent latches. However, the elevator in  FIG.  16    illustrates locks  322   a - b ,  324   a - b ,  326   a - b ,  328   a - b  for respective jaws  110   a - b ,  120   a - b ,  130   a - b ,  140   a - b  that retain the lateral portion  112 ,  116 ,  122 ,  126 ,  132 ,  136 ,  142 ,  146  of each jaw to the respective attachment portion  180 ,  181 ,  182 ,  183 ,  184 ,  185 ,  186 ,  187  of each jaw. The lock for the jaw  110   a  will now be described with its description being generally applicable to the other jaws  110   b ,  120   a - b ,  130   a - b ,  140   a - b.    
     The jaw  110   a  includes a lateral portion  112  with a protruding lip  310  that can be inserted into a recess  312  in the attachment portion  180 . A lock  322   a  can extend through the jaw where recess  312  straddles the lip  310 . The lock can be rotated to secure the lateral portion  112  to the attachment portion  180 , or rotated to release the lateral portion  112  from the attachment portion  180 . The lock  322   a  can have a feature that has a smaller width in a first position and a wider width in second position. Rotating the lock  322   a  rotates the feature between first and second positions. When the feature is in the smaller width position, the lateral portion  112  can be removed from or inserted into the attachment portion  180 . When the feature is in the wider width position, the lateral portion  112  can be secured to the attachment portion  180  to prevent removal of the lip  310  from the recess  312 . However, the lock  322   a  can be configured to allow some relative axial motion between the lip  310  and the recess  312 , such that forces applied to the latch  110  when it is in an engaged position and a tubular  38  is engaged with the latch  110  are prevented (or at least minimized) from being transmitted through the lateral portion  112  to the attachment portion  180  via engagement of the lip  310  with the recess  312 . This can reduce forces experienced by the drive shaft  162  during operation of the elevator  100 . To remove the lateral portion  112  (and thus the engagement portion  114 ) from the attachment portion  180 , the lock  322   a  can be disengaged allowing the lip  310  to be removed from the recess  312 . 
       FIG.  17    shows a cross-sectional view of the elevator  100  as indicated by the section lines  17 - 17  shown in  FIG.  16   . Section  17 - 17  is generally toward the back of the elevator  100  at about a center point of the drive shafts  166 ,  168 ,  176 , and  178 . Therefore, most of the front latches  110 ,  130  are not shown with only about half of the attachment portions  182 ,  183 ,  186 , and  187  shown. However,  FIG.  17    provides a view of the interaction of the locks  324   a - b  with stand offs  320   a - b  mounted to the housing  102  just outside of the space ring  108 . When the latches are rotated about their respective axes to the engaged position, a rotational force applied by the rotary actuators on the latches can be up to 10 metric tons (i.e., ˜11 US short tons). This sustained force on the latches when they are in the engaged position can cause issues with a weight measurement of an engaged tubular  38  (such as a drill string) by the elevator  100 . Stand-offs  320   a - b  can be installed in the elevator  100 . The stand-offs can be positioned outside of the spacer ring  108  and attached to the housing  102 . The height of each stand-off  320   a - b  can be adjusted such that when the latch  120  is engaged, the locks  322   a - b  engage the stand-offs  320   a - b , respectively, such that the 10 metric ton rotational forces can be transmitted to the housing  102  through the stand-offs  320   a - b  and not through the spacer ring  108 . Therefore, any additional weight applied to the engaged latches by the engaged tubular  38  can be transmitted to the housing through the spacer ring  108  and a more accurate measurement of the tubular  38  weight can be determined. A circular weight sensor  480  can be used, instead of the compression sensors  188 ,  189 , to measure the weight of the tubular  38  being held by the elevator  100 . The circular weight sensor  480  will be described in more detail below regarding  FIGS.  25 - 28 B . 
       FIG.  18    shows another cross-sectional view of the elevator  100  as indicated by the section lines  17 - 17  shown in  FIG.  16   . However, in this configuration, all latches  110 ,  120 ,  130 ,  140  are in the engaged position. The rotational forces applied to the latches  120 ,  140  can be transmitted through the locks  328   a - b  to the locks  324   a - b  to the stand-offs  320   a - b , respectively. Not shown, but similar to latches  120 ,  140 , the rotational forces applied to the latches  110 ,  130  can be transmitted through the locks  326   a - b  to the locks  322   a - b  to stand-offs attached to the housing similar to stand-offs  320   a - b , respectively. 
       FIG.  19    shows a cross-sectional view of the elevator  100  as indicated by the section lines  19 - 19  shown in  FIG.  16   . Section  19 - 19  is generally at the center of the elevator  100 . This view shows a retention mechanism  330   a . A lever  332   a  can be connected to one end of a shaft  338   a  with a cam  334   a  attached at an opposite end of the shaft  338   a . When the lever  332   a  is rotated the cam  334   a  is rotated to engage or disengage the cam  334   a  with a groove  336   a  in the spacer ring  108 . When the cam  334   a  is engaged with the groove  336   a , the spacer ring is prevented from being removed from the elevator  100 . When the cam  334   a  is disengaged from the groove  336   a , the spacer ring is permitted to be removed from the elevator  100 . A second retention mechanism  330   b  can also be used to permit or prevent removal of the spacer ring  108  from the elevator  100 . A lever  332   b  can be connected to one end of a shaft  338   b  with a cam  334   b  attached at an opposite end of the shaft  338   b . Rotating the lever  332   b  rotates the cam  334   b  and causes the cam  334   b  to engage or disengage a groove  336   b  in the spacer ring  108 . When the cam  334   b  is engaged with the groove  336   b , the spacer ring is prevented from being removed from the elevator  100 . When the cam  334   b  is disengaged from the groove  336   b , the spacer ring is permitted to be removed from the elevator  100 . 
     It should be understood that the cams  334   a, b  can be rotated into the engaged or disengaged positions by rotating the respective shafts  338   a, b . The shafts  338   a, b  can be rotated manually by using a tool to apply a rotational force to the shafts  338   a, b . Alternatively, or in addition to, the cams  334   a, b  can be rotated into the engaged position by the respective levers  332   a, b  when an adjacent jaw is rotated to their engaged position. Therefore, if the cam  334   a  has not yet been rotated into its engaged position when the elevator  100  is deployed, rotating either of the jaws  110   a ,  120   a  into its engaged position can engage the lever  332   a  and rotate the cam  334   a  into its engaged position. Additionally, if the cam  334   b  has not yet been rotated into its engaged position when the elevator  100  is deployed, rotating either of the jaws  110   b ,  120   b  into its engaged position can engage the lever  332   b  and rotate the cam  334   b  into its engaged position. In this way, the cams  334   a, b  can be forced into their engaged position by engaging the jaws to ensure retention of the locking ring  108  during elevator  100  operation. 
       FIG.  20    is an enlarged perspective view of a portion of the elevator  100  that interfaces to one of the links  44 . A link retainer  400  can be removably attached to retain the link  44  to an elevator support  402  once the elevator support  402  has been inserted through an opening in the link  44 . When installed, the link retainer  400  can prevent removal of the link from the elevator  100  until the link retainer is disengaged. 
       FIG.  21    is a perspective view of a link retainer  400  that can be removably attached to the elevator  100  at a support  402  as indicated in  FIG.  5   . An example of the link retainer  400  shown in  FIG.  21    includes a retainer mount  420  and a removable device  410 . The retainer mount  420  can include a mounting flange  425  with mounting holes  424  for securing the retainer mount  420  to the support  402  with fasteners (not shown). However, the retainer support  420  can be attached to the support  402  by other attachment means, such as welding, bonding, etc. as long as the attachment means secures the retainer support  420  to the support  402  and does not interfere with the operation of the link retainer  400 . The retainer mount  420  can include a retention feature  422  that extends from the mounting flange with protrusions  426  that extend from opposite sides of the retention feature  422 . A gap  428  between the protrusions  426  and the mounting flange  425  can have a length L 1  that provides a necessary clearance for operating the link retainer  400 . 
     The removable device  410  can include a first plate  404 , and a second plate  406  slidably connected to the first plate  404  by fasteners  416 . The first plate  404  and the second plate  406  can be biased apart from each other by biasing devices  408  disposed between them. The biasing devices  408  urge the second plate  406  to the ends of the fasteners  416 . The first and second plates  404 ,  406  can have an opening  412  that is complimentarily shaped to allow the protrusions  426  of the retainer mount  420  to pass through the openings  412 . The openings  412  require the removable device  410  to be aligned with the shape of the protrusions  426  to allow the removable device  410  to receive the protrusions  426  into the openings  412  (see  FIG.  22   ). When the protrusions  426  and the openings  412  are aligned, the first plate  404  can engage the mounting flange  425 . However, since the biasing devices  408  urge the first and second plates  404 ,  406  away from each other, the removable device  410  cannot be rotated relative to the protrusions  426  (and retention feature  422 ) because the distance the mounting flange  425  to the opposite side of the second plate  406  is larger than the gap  428 . 
       FIG.  23    shows the removable device  410  mounted onto the retainer mount  420  with a compression force applied to the second plate  406  via the compression handles  418 , thereby compressing the springs  418  and reducing the distance from the mounting flange  425  to the opposite side of the second plate  406  to be less than the gap  428 . In this configuration, the protrusions  426  are above the opposite side of the second plate  406  and the removable retainer  410  can be rotated as shown by arrows  430  to align the protrusions  426  with the recesses  414 . With the protrusions  426  aligned with the recesses  414 , the compression force applied to the compression handles  418  can be released and the biasing devices  408  will again urge the first and second plates  404 ,  406  away from each other forcing the protrusions  426  into the recesses  414 . With the protrusions  426  seated in the recesses  414 , the removable device  410  is prevented from rotating further and thereby secures the removable device  410  to the retainer mount  420 . 
       FIG.  24    is a cross-sectional view of the link retainer  400  with the protrusions  426  seated in the recesses  414 . It should be understood that the protrusions can be various shapes and sizes as long as the openings  412  match those shapes and sizes with appropriate clearances, and that the rotation into the secured position is possible. 
       FIG.  25    shows an elevator with a link interface system  230  that can include link interfaces  222 ,  224  which are similar to the link interface  222  shown in  FIG.  14 B  that has adjustable angled flanges  226   a ,  226   b .  FIG.  25    also shows a link retainer  400  with extended handles  418  that can include an opening for improved operator grasping and manipulation of the handles  418 . 
       FIG.  25    is a representative perspective view a housing  102  of an elevator  100  with latch assemblies of the elevator  100  removed to observe a circular weight sensor  480  positioned around a center of the elevator  100 . A spacer ring  108  (not shown) can be mounted above it and transfer weight of a tubular  34  captured in the elevator  100  to the circular weight sensor  480 . In operation of the elevator  100 , the latches, when in a closed position, will engage the spacer ring  108  and, through the spacer ring  108 , transfer the weight of a captured tubular  34  to the circular weight sensor  480 . 
       FIG.  26    is a representative perspective view of a circular weight sensor  480 . A support ring  460  engages the elevator housing  102  when the circular weight sensor  480  is installed in the elevator  100 . An engagement ring  470  is slidably and sealingly engaged with the support ring  460  creating a sealed chamber  454  between them (see  FIG.  27   ). A fill port  462  can be used to fill the sealed chamber  454  with an incompressible fluid (e.g., oil). A retainer ring  464  can be used to prevent disengagement of the engagement ring  470  from the support ring  460 , with fasteners  466  being used to secure the retainer ring  464  to the support ring  460 . The engagement ring  470  is allowed to float relative to the support ring  460  and the retainer ring  464 . An outlet port  450  can be used to connect the circular weight sensor  480  to a reservoir  500  that can measure pressure applied to the sealed chamber  454  by the engagement ring  470 . 
       FIG.  27    a representative partial cross-sectional view of the circular weight sensor  480  of  FIG.  26    along section line  27 - 27 . The outlet port  450  can include a pressure fitting with an internal flow passage  452  that provides fluid and pressure communication between the reservoir  500  and the sealed chamber  454 . The pressure fitting of the outlet port  450  can be threaded into (or otherwise attached) to the borehole  453  of the support ring  460 . A flow passage  476  can provide fluid and pressure communication between the borehole  453  and the sealed chamber  454 . The fill port  462  can be used to fill the sealed chamber  454  with an incompressible fluid (e.g., oil). When the chamber  454  is filled with the incompressible fluid, a plug can be installed in the fill port  462  to prevent loss of the incompressible fluid. 
     When installed, the bottom surface  472  of the support ring  460  can engage the housing  102  of the elevator  100 . One or more alignment pins  468  can be used to ensure proper alignment of the circular weight sensor  480  to the housing  102 . The top surface  478  of the engagement ring  470  can engage the spacer ring  108 . Therefore, when weight is transferred to the spacer ring  108  from the latches of the elevator, then the spacer ring  108  transfers that weight to the engagement ring  470  via the top surface  478 . The fasteners  466  can be used to attach the retainer ring  464  to the support ring  460 . When the sealed chamber  454  is filled, the engagement ring  470  is raised up away from the support ring  460  to engage the retainer ring  464 . A gap L 3  can be formed between a lower internal surface of the engagement ring  470  and an upper internal surface of the support ring  460 . This creates a volume between the engagement ring  470  and the support ring  460  that is the sealed chamber  454 . The seals  458  can be used to generally prevent fluid communication between the sealed chamber  454  and the external environment. However, fluid communication is allowed through the outlet port  450  to the reservoir  500 . The seal  474  can be used to seal the circular weight sensor  480  to the housing  102 , thereby preventing (or at least minimizing) ingress of operational fluids and debris when the elevator  100  is operating. 
       FIG.  28 A  is a representative side view of a reservoir  500  with a pressure sensor  510 .  FIG.  28 B  is a representative cross-sectional view of the reservoir  500  shown in  FIG.  28 A . The reservoir  500  can be in fluid and pressure communication with the sealed chamber  454  of the circular weight sensor  480  via a flow passage (not shown) connected between an inlet port  512  of the reservoir  500  and the outlet port  450  of the circular weight sensor  480 . Therefore, when compression forces act on the top surface  478  of the circular weight sensor  480 , pressure on the incompressible fluid contained within the sealed chamber  454  can vary. Increased compression forces can increase pressure in the sealed chamber  454 , and decreased compression forces can decrease pressure in the sealed chamber  454 . The incompressible fluid contained with the sealed chamber  454  can communicate pressure changes in the sealed chamber  454  to a chamber  520  in the reservoir  500 . The reservoir  500  can include a pressure sensor  510  that is in pressure communication with the chamber  520 . 
     The reservoir  500  can include a body section  516  that can be sealed on each end by a top cap  514 , a bottom cap  506 , and seals  518 . The top cap  514  can include a borehole  526  with a piston  504  that sealingly engages the borehole  526  via the seal  528 . One end of the piston  504  can be in pressure and fluid communication with the chamber  520  with the other end of the piston  504  being in pressure and fluid communication with a chamber  502 . The piston  504  can also sealing engage, via a seal  530 , an inner surface  532  of the body  516 . A biasing device  508  can be disposed between the piston  504  and the bottom end cap  506  to provide a biasing force against the piston  504 . The chamber  502  can be in fluid communication with an external environment  524  via the flow passage  522 . Therefore, when the piston  504  compresses the biasing device  508 , pressure in the chamber  502  remains equalized with the external environment  524  because of the flow passage  522 . The biasing device  508  allows the piston  504  to move along the inner surface  532  toward the bottom cap  506  when pressure in the chamber  520  in increased and allows the piston  504  to move along the inner surface  532  toward the top cap  514  when pressure in the chamber  520  decreases. 
     In operation, when the circular weight sensor  480  is installed in the elevator  100 , the bottom surface  472  of the support ring  460  can engage the housing  102  and the top surface  478  of the engagement ring  470  can engage the spacer ring  108 . When a tubular  34  is captured by the elevator  100  the weight of the tubular  34  can be transferred from the latches of the elevator  100  to the spacer ring  108 , which can then transfer the weight of the tubular to the housing  102  (see  FIG.  8 A ) through the circular weight sensor  480 . The weight acting on the top surface  478  can increase pressure on the incompressible fluid in the sealed chamber  454 . The increased pressure can be communicated to the chamber  520  in the reservoir  500  where the increase pressure can act on the piston  504  moving the piston  504  toward the bottom end cap  506 , thereby increasing a volume of the chamber  520 . The pressure sensor  510  can sense the pressure (continuously, or randomly, or periodically, etc.) in the chamber and communicate the pressure sensor data to a rig controller via wired or wireless communication. If the weight acting on the top surface  478  is decreased, then pressure on the incompressible fluid in the sealed chamber  454  can decrease. This pressure change can be communicated to the chamber  520  in the reservoir  500  causing the biasing device  508  to move the piston  504  toward the top cap  514 , thereby decreasing the volume of the chamber  520 . Again, the pressure sensor  510  can sense the pressure (continuously, or randomly, or periodically, etc.) in the chamber and communicate the pressure sensor data to a rig controller  50  via wired or wireless communication. Additionally, the pressure sensor  510  can communicate the pressure sensor data to a local controller in the enclosure  150  via wired or wireless communication, which can communicate to the rig controller  50  via wired or wireless communication. 
     Various Embodiments 
     One general aspect includes a system for conducting subterranean operations including: an elevator configured to move a tubular, the elevator including: a housing defining a central bore configured to receive the tubular therein; a first latch including first and second jaws, with each of the first and second jaws being coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the first and second jaws are in the engaged position, engagement portions of the first and second jaws are positioned in the central bore on opposite sides of, with respect to each other, a central axis of the central bore and define an opening of a first diameter; and a second latch including third and fourth jaws, with each of the third and fourth jaws coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the third and fourth jaws are in the engaged position, engagement portions of the third and fourth jaws are positioned in the central bore on opposite sides of, with respect to each other, the central axis of the central bore and define an opening of a second diameter which is different than the first diameter, where the first jaw is fixedly attached to a first drive shaft and the first drive shaft is rotationally attached to the housing, where the third jaw is fixedly attached to a third drive shaft and the third drive shaft is rotationally attached to the housing, and where the first and third drive shafts independently rotate the first and third jaws, respectively, about a first axis. 
     Embodiments may include one or more of the following features. The system where the second jaw is fixedly attached to a second drive shaft and the second drive shaft is rotationally attached to the housing. The system may also include where the fourth jaw is fixedly attached to a fourth drive shaft and the fourth drive shaft is rotationally attached to the housing. The system may also include where the second and fourth drive shafts independently rotate the second and fourth jaws, respectively, about a second axis. The system where the first and second jaws are positioned on opposite sides of the central axis, and when the first and second jaws rotate to the engaged position the first and second jaws rotate toward each other, and when the first and second jaws rotate to the disengaged position the first and second jaws rotate away from each other. The system where the third and fourth jaws are positioned on opposite sides of the central axis, and when the third and fourth jaws rotate to the engaged position the third and fourth jaws rotate toward each other, and when the third and fourth jaws rotate to the disengaged position the third and fourth jaws rotate away from each other. The system where each of the engagement portions of the first and second jaws has a lateral portion and a tapered portion, with the tapered portion extending from the lateral portion at an angle. The system where the lateral portion of the first jaw is substantially parallel to the lateral portion of the second jaw when the first and second jaws are in the engaged position. The system where the tapered portions of the first and second jaws are configured to form a first frustoconically shaped portion of the first latch when the first and second jaws are in the engaged position, with each of the tapered portions including: an inner surface having a concave contour and being joined to a top surface of respective ones of the first and second jaws; a distal surface joined to the inner surface at an engagement edge; and an outer surface joined to the distal surface at a bottom edge and joined to a bottom surface of the respective ones of the first and second jaws. 
     The system where the inner and distal surfaces are tapered and angled relative to the central axis. The system where the inner surface is angled from the top surface of the respective jaw toward the central axis to the engagement edge, and the distal surface is angled from the engagement edge away from the central axis to the bottom edge. The system where the engagement edge or the inner surface is configured to engage a portion of the tubular when the first and second jaws are in the engaged position. The system where the elevator is configured to be EX-certified according to EX zone 1 (ATEX/IECEx), and an electronics controller configured to control the elevator is disposed within a chamber of the housing. The system where a rotary actuator is coupled to the first and second drive shafts and simultaneously rotates the first and second drive shafts in opposite directions, thereby rotating the first and second jaws between engaged and disengaged positions. The system where the first and second drive shafts extend through a wall of the housing, and where each one of the first and second drive shafts engage one or more seals, thereby preventing fluid communication through the wall at either of the first and second drive shafts. The system where the rotary actuator is disposed in a chamber within the housing, the chamber being sealed to prevent environmental fluids or debris from entering the chamber. The system where the second latch engages the first latch when the first and second latches are in the engaged position. The system where the first and second jaws of the first latch are configured to form a first frustoconically shaped portion of the first latch when the first latch is in the engaged position. The system may also include where the third and fourth jaws of the first latch are configured to form a second frustoconically shaped portion of the second latch when the second latch is in the engaged position. 
     The system may also include where a majority of an outer surface of the second frustoconically shaped portion abuts an inner surface of the first frustoconically shaped portion when the first and second latches are in the engaged position. The system where the first frustoconically shaped portion includes a first gap between the first and second jaws when the first latch is in the engaged position, and where the second frustoconically shaped portion includes a second gap between the third and fourth jaws when the second latch is in the engaged position. The system where the first and second gaps are parallel to the central axis of the housing, and the first and second gaps are circumferentially aligned with each other relative to the central axis. The system where the first and second gaps are parallel to the central axis of the housing, and the first gap is circumferentially offset, relative to the central axis, from the second gap. The system where each of the engagement portions of the first, second, third, and fourth jaws has a lateral portion and a tapered portion, with the tapered portion extending from the lateral portion at an angle. The system where the lateral portion of the first jaw is parallel to the lateral portion of the second jaw when the first and second jaws are in the engaged position, where the lateral portion of the third jaw is parallel to the lateral portion of the fourth jaw when the third and fourth jaws are in the engaged position, and where a majority of the engagement portions of the third and fourth jaws overlie the engagement portions of the first and second jaws when the first, second, third, and fourth jaws are in the engaged position. 
     The system where the tapered portions of the first and second jaws are configured to form a first frustoconically shaped portion of the first latch when the first and second jaws are in the engaged position, and where the tapered portions of the third and fourth jaws are configured to form a second frustoconically shaped portion of the second latch when the third and fourth jaws are in the engaged position, with each of the tapered portions including: an inner surface having a concave contour and being joined to a top surface of respective ones of the jaws; a distal surface joined to the inner surface at an engagement edge; and an outer surface joined to the distal surface at a bottom edge and joined to a bottom surface of the respective ones of the jaws. The system where the inner and distal surfaces are tapered and angled relative to the central axis. 
     The system where the inner surface is angled from the top surface of the respective jaw toward the central axis to the engagement edge, and the distal surface is angled from the engagement edge away from the central axis to the bottom edge. The system where at least one of the engagement edges or the inner surfaces is configured to engage a portion of the tubular when the jaws are in the engaged position. The system where a minimum diameter of the second frustoconically shaped portion is smaller than a minimum diameter of the first frustoconically shaped portion. The system where the tapered portions of the third and fourth jaws engage the tapered portions of the first and second jaws and the lateral portions of the third and fourth jaws engage the lateral portions of the first and second jaws when the jaws are in the engaged position. The system may also include where a perimeter ridge at a top of the tapered portions of the first and second jaws extends into a perimeter recess in a surface of the lateral portions of the third and fourth jaws that engage the first and second jaws when the jaws are in the engaged position. The system where a first rotary actuator is coupled to the first and second drive shafts and simultaneously rotates the first and second drive shafts in opposite directions, thereby rotating the first and second jaws between engaged and disengaged positions. 
     The system may also include where a second rotary actuator is coupled to the third and fourth drive shafts and simultaneously rotates the third and fourth drive shafts in opposite directions, thereby rotating the third and fourth jaws between engaged and disengaged positions. The system where the first and second drive shafts extend through a wall of the housing, and where each one of the first and second drive shafts engage one or more seals, thereby preventing fluid communication through the wall at either of the first and second drive shafts. The system may also include where the third and fourth drive shafts extend through a wall of the housing, and where each one of the third and fourth drive shafts engage one or more seals, thereby preventing fluid communication through the wall at either of the third and fourth drive shafts. The system where the rotary actuators are disposed in a chamber within the housing, the chamber being sealed to prevent environmental fluids or debris from entering the chamber. 
     The system further including: a third latch including fifth and sixth jaws, with each of the fifth and sixth jaws coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the fifth and sixth jaws are in the engaged position, engagement portions of the fifth and sixth jaws are positioned in the central bore on opposite sides of, with respect to each other, the central axis of the central bore and define an opening of a third diameter which is different than the first and second diameters, and a fourth latch including seventh and eighth jaws, with each of the seventh and eighth jaws coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the seventh and eighth jaws are in the engaged position, engagement portions of the seventh and eighth jaws are positioned in the central bore on opposite sides of, with respect to each other, the central axis of the central bore and define an opening of a fourth diameter which is different than the first, second, and third diameters where the engagement portions of the fifth and sixth jaws are configured to be nested in the engagement portions of the third and fourth jaws when the fifth and sixth jaws are in the engaged position, and where the engagement portions of the seventh and eighth jaws are configured to be nested in the engagement portions of the fifth and sixth jaws when the seventh and eighth jaws are in the engaged position. The system where the fifth jaw is fixedly attached to a fifth drive shaft and the fifth drive shaft is rotationally attached to the housing. 
     The system may also include where the sixth jaw is fixedly attached to a sixth drive shaft and the sixth drive shaft is rotationally attached to the housing. The system may also include where the seventh jaw is fixedly attached to a seventh drive shaft and the seventh drive shaft is rotationally attached to the housing. The system may also include where the eighth jaw is fixedly attached to an eighth drive shaft and the eighth drive shaft is rotationally attached to the housing. The system may also include where the fifth and seventh drive shafts independently rotate the fifth and seventh jaws, respectively, about a third axis. The system may also include where the sixth and eighth drive shafts independently rotate the sixth and eighth jaws, respectively, about a fourth axis. The system where the first and second axes are disposed on opposite sides of the central axis of the housing and at a same longitudinal position along the central axis, where the third and fourth axes are disposed on opposite sides of the central axis and at a same longitudinal position along the central axis, and where the first and second axes are positioned radially inward from the third and fourth axes. The system where when the first latch rotates to the engaged position the first and second jaws rotate toward each other, and when the first latch rotates to the disengaged position the first and second jaws rotate away from each other. 
     The system may also include where when the second latch rotates to the engaged position the third and fourth jaws rotate toward each other, and when the second latch rotates to the disengaged position the third and fourth jaws rotate away from each other. The system where when the third latch rotates to the engaged position the fifth and sixth jaws rotate toward each other, and when the third latch rotates to the disengaged position the fifth and sixth jaws rotate away from each other. The system may also include where when the fourth latch rotates to the engaged position the seventh and eighth jaws rotate toward each other, and when the fourth latch rotates to the disengaged position the seventh and eighth jaws rotate away from each other. The system where each of the engagement portions of the first, second, third, fourth, fifth, sixth, seventh, and eighth jaws has a lateral portion and a tapered portion, with the tapered portion extending from the lateral portion at an angle. The system may also include where the lateral portion of the first jaw is parallel to the lateral portion of the second jaw when the first latch is in the engaged position. The system may also include where the lateral portion of the third jaw is parallel to the lateral portion of the fourth jaw when the second latch is in the engaged position. The system may also include where the lateral portion of the fifth jaw is parallel to the lateral portion of the sixth jaw when the third latch is in the engaged position. The system may also include where the lateral portion of the seventh jaw is parallel to the lateral portion of the eighth jaw when the fourth latch is in the engaged position. 
     The system may also include where the tapered portions of the first and second jaws are configured to form a first frustoconically shaped portion when the first latch is in the engaged position. The system may also include where the tapered portions of the third and fourth jaws are configured to form a second frustoconically shaped portion when the second latch is in the engaged position. The system may also include where the tapered portions of the fifth and sixth jaws are configured to form a third frustoconically shaped portion when the third latch is in the engaged position. The system may also include where the tapered portions of the seventh and eighth jaws are configured to form a fourth frustoconically shaped portion when the fourth latch is in the engaged position, with each of the tapered portions including: an inner surface having a concave contour and being joined to a top surface of respective ones of the jaws, a distal surface joined to the inner surface at an engagement edge, and an outer surface joined to the distal surface at a bottom edge and joined to a bottom surface of the respective ones of the jaws. The system where the inner and distal surfaces are tapered and angled relative to the central axis. The system where the inner surface is angled from the top surface of the respective jaw toward the central axis to the engagement edge, and the distal surface is angled from the engagement edge away from the central axis to the bottom edge. The system where the engagement edge or the inner surface is configured to engage a portion of the tubular when at least one of the latches is in the engaged position. The system may also include the first jaw is fixedly attached to a first drive shaft that is rotationally attached to the housing. 
     The system may also include the second jaw is fixedly attached to a second drive shaft that is rotationally attached to the housing. The system may also include the third jaw is fixedly attached to a third drive shaft that is rotationally attached to the housing. The system may also include the fourth jaw is fixedly attached to a fourth drive shaft that is rotationally attached to the housing. The system may also include where a first rotary actuator is coupled to the first and second drive shafts and simultaneously rotates the first and second drive shafts in opposite directions, thereby rotating the first and second jaws between engaged and disengaged positions. The system may also include where a second rotary actuator is coupled to the third and fourth drive shafts and simultaneously rotates the third and fourth drive shafts in opposite directions, thereby rotating the third and fourth jaws between engaged and disengaged positions. The system may also include the fifth jaw is fixedly attached to a fifth drive shaft that is rotationally attached to the housing. The system may also include the sixth jaw is fixedly attached to a sixth drive shaft that is rotationally attached to the housing. The system may also include the seventh jaw is fixedly attached to a seventh drive shaft that is rotationally attached to the housing. The system may also include the eighth jaw is fixedly attached to an eighth drive shaft that is rotationally attached to the housing. 
     The system may also include where a third rotary actuator is coupled to the fifth and sixth drive shafts and simultaneously rotates the fifth and sixth drive shafts in opposite directions, thereby rotating the fifth and sixth jaws between engaged and disengaged positions. The system may also include where a fourth rotary actuator is coupled to the seventh and eighth drive shafts and simultaneously rotates the seventh and eighth drive shafts in opposite directions, thereby rotating the seventh and eighth jaws between engaged and disengaged positions. The system where each one of the drive shafts extend through a wall of the housing, and where each one of the drive shafts engage one or more seals, thereby preventing fluid communication through the wall at any of the drive shafts. The system where the rotary actuators are disposed in a chamber within the housing, the chamber being sealed to prevent environmental fluids or debris from entering the chamber. The system where the second latch engages the first latch when the first and second latches are in the engaged position. The system where the third latch engages the second latch when the second and third latches are in the engaged position. The system where the fourth latch engages the third latch when the third and fourth latches are in the engaged position. The system where the first and second jaws of the first latch are configured to form a first frustoconically shaped portion of the first latch when the first latch is in the engaged position. 
     The system may also include where the third and fourth jaws of the first latch are configured to form a second frustoconically shaped portion of the second latch when the second latch is in the engaged position. The system may also include where a majority of an outer surface of the second frustoconically shaped portion abuts an inner surface of the first frustoconically shaped portion when the first and second latches are in the engaged position. The system where the first frustoconically shaped portion includes a first gap between the first and second jaws when the first latch is in the engaged position. The system may also include where the second frustoconically shaped portion includes a second gap between the third and fourth jaws when the second latch is in the engaged position. The system where the first and second gaps are parallel to the central axis of the housing, and the first and second gaps are circumferentially aligned with each other relative to the central axis. The system where the first and second gaps are parallel to the central axis of the housing, and the first gap is circumferentially offset, relative to the central axis, from the second gap. The system where the fifth and sixth jaws of the third latch are configured to form a third frustoconically shaped portion of the third latch when the third latch is in the engaged position. The system may also include where a majority of an outer surface of the third frustoconically shaped portion abuts an inner surface of the second frustoconically shaped portion when the second and third latches are in the engaged position. The system where the seventh and eighth jaws of the fourth latch are configured to form a fourth frustoconically shaped portion of the fourth latch when the fourth latch is in the engaged position. 
     The system may also include where a majority of an outer surface of the fourth frustoconically shaped portion abuts an inner surface of the third frustoconically shaped portion when the third and fourth latches are in the engaged position. The system where the third frustoconically shaped portion includes a third gap between the fifth and sixth jaws when the third latch is in the engaged position. The system may also include where the fourth frustoconically shaped portion includes a fourth gap between the seventh and eighth jaws when the fourth latch is in the engaged position. The system where the third and fourth gaps are parallel to the central axis of the housing, and the third and fourth gaps are circumferentially aligned with each other relative to the central axis. The system where the third and fourth gaps are parallel to the central axis of the housing, and the third gap is circumferentially offset, relative to the central axis, from the fourth gap. 
     The system further including a link interface system configured to rotate the housing up to greater than 90 degrees about a housing axis, the housing axis being perpendicular to the central axis, the link interface system including a rotary actuator, the rotary actuator including a body and a drive shaft, where the body is fixedly attached to the housing and the drive shaft is coupled to a link interface that is rotationally attached to the housing, and where when the drive shaft is rotated by the rotary actuator, the link interface is rotated about the housing axis. The system further including a link interface system configured to rotate the housing about a housing axis, the housing axis being perpendicular to the central axis, where the link interface is configured to engage a pair of links and rotate the housing relative to the links within a range of +/−4 degrees, +/−8 degrees, +/−12 degrees, +/−16 degrees, +/−20 degrees, +/−24 degrees, +/−28 degrees, +/−32 degrees, +/−36 degrees, +/−40 degrees, +/−44 degrees, +/−48 degrees, +/−52 degrees, +/−56 degrees, +/−60 degrees, +/−64 degrees, +/−68 degrees, +/−72 degrees, +/−76 degrees, +/−80 degrees, +/−84 degrees, +/−88 degrees, +/−92 degrees, +/−95 degrees, +/−96 degrees, +/−100 degrees, and +/−102 degrees, relative to an axis of at least one of the links. The system further including a hydraulic generator and an energy storage device, where the hydraulic generator generates electrical energy for operation of the elevator and stores a portion of the electrical energy in the energy storage device. The system where the storage device is a capacitor assembly. The system where the elevator is configured to be ATEX certified or IECEx certified according to ex zone 1 requirements. The system where the elevator, with the housing in a substantially horizontal orientation, is configured to support a tubular that weighs up to 1180 metric tons (˜ 1300 short tons), or up to 1134 metric tons (˜1250 short tons), or up to 1189 metric tons (˜ 1200 short tons), or up to 907 metric tons (˜1000 short tons), or up to 680 metric tons (˜750 short tons), or up to 454 metric tons (˜500 short tons), or up to 318 metric tons (˜350 short tons), or up to 227 metric tons (˜250 short tons). The system further including a top drive coupled to the elevator housing via a pair of links, with each of the links rotationally attached to the top drive at one end and rotationally attached to the housing at an opposite end. 
     The system further including a first lock for the first jaw, where the first lock retains a lateral portion of the first jaw to an attachment portion of the first jaw, and where the attachment portion of the first jaw is fixedly attached to the first drive shaft. The system further including a third lock for the third jaw, where the third lock retains a lateral portion of the third jaw to an attachment portion of the third jaw, and where the attachment portion of the third jaw is fixedly attached to the third drive shaft. The first lock engages a portion of the housing adjacent a spacer ring in the elevator when the first jaw is in the engaged position, and the third lock engages the first lock when the third jaw is in the engaged position, and where hydraulic force applied to the first and third jaws by rotary actuators is transferred through the first and third locks to the housing, thereby bypassing the spacer ring. 
     The system further including a spacer ring that engages the first and second jaws when the first and second jaws are in the engaged position, a shaft in the housing with a lever on one end and a cam on an opposite end, where rotation of the shaft engages the cam with a recess in the spacer ring, such that removal of the spacer ring from the housing is prevented. The shaft is rotated when the first jaw is rotated into the engaged position. 
     The system further including a pair of link interfaces configured to rotatably attach a pair of links to respective supports of the elevator that extend from opposite sides of the elevator, wherein each link is retained on the respective support by a removable device, and where the removable device can be installed by aligning an opening through the removable device with a retention feature of a retainer mount, receiving the retention feature within the opening, compressing two plates of the removable device together, rotating the removable device relative to the retention feature, and releasing the two plates to expand away from each other when the retention feature aligns with recesses on the removable device, thereby securing the removable device on the support. 
     One general aspect includes a system for conducting subterranean operations including: an elevator configured to move a tubular, the elevator including: a housing defining a central bore configured to receive the tubular therein, the central bore having a central axis; and a link interface system configured to rotate the housing up to greater than 90 degrees about a housing axis. 
     Embodiments may include one or more of the following features. The system where the link interface system is configured to engage a pair of links and rotate the housing relative to the links within a range of +/−4 degrees, +/−8 degrees, +/−12 degrees, +/−16 degrees, +/−20 degrees, +/−24 degrees, +/−28 degrees, +/−32 degrees, +/−36 degrees, +/−40 degrees, +/−44 degrees, +/−48 degrees, +/−52 degrees, +/−56 degrees, +/−60 degrees, +/−64 degrees, +/−68 degrees, +/−72 degrees, +/−76 degrees, +/−80 degrees, +/−84 degrees, +/−88 degrees, +/−92 degrees, +/−95 degrees, +/−96 degrees, +/−100 degrees, and +/−102 degrees relative to an axis of at least one of the links. The system further including a hydraulic generator and an energy storage device, where the hydraulic generator generates electrical energy for operation of the elevator and stores a portion of the electrical energy in the energy storage device. The system where the storage device is a capacitive assembly. The system where the elevator is configured to be ATEX certified or IECEx certified according to EX Zone 1 requirements. The system where the elevator, with the housing in a substantially horizontal orientation, is configured to support a tubular that weighs up to 1180 metric tons (˜ 1300 short tons), or up to 1134 metric tons (˜ 1250 short tons), or up to 1189 metric tons (˜ 1200 short tons), or up to 907 metric tons (˜ 1000 short tons), or up to 680 metric tons (˜ 750 short tons), or up to 454 metric tons (˜ 500 short tons), or up to 318 metric tons (˜ 350 short tons), or up to 227 metric tons (˜ 250 short tons). The system where the elevator is configured to manipulate the tubular between horizontal and vertical orientations, and where the tubular weighs up to 3000 kg (˜ 3 short tons). The system where the elevator further includes one or more sensors disposed between a spacer ring and the housing, and a controller, where the sensors detect a force applied between the spacer ring and the housing, and the controller is configured to determine a weight of the tubular supported by the elevator. 
     The system further including a top drive coupled to the elevator housing via a pair of links, with each of the links rotationally attached to the top drive at one end and rotationally attached to the housing at an opposite end. The system where the housing axis is perpendicular to the central axis, where the link interface system includes a rotary actuator having a body and a drive shaft, with the body fixedly attached to the housing and the drive shaft coupled to a link interface that is rotationally attached to the housing, and where when the drive shaft is rotated by the rotary actuator, the link interface is rotated about the housing axis. The system further including a sensor that detects an angular position of the housing relative to the link interface, where the sensor is disposed within a sealed chamber of the housing that prevents a portion of environmental fluids from entering the sealed chamber during the subterranean operations. The system further including a rotary actuator coupled to each pair of jaws of the elevator and a sensor coupled to each rotary actuator, where the sensor detects an angular position of the rotary actuator, and a controller is configured to determine whether one or more of the jaws are in an engaged or disengaged position. The system further including: a rig; a top drive supported by the rig; a pair of links rotatably attached to the top drive; and the elevator rotatably attached to the pair of links. The system further including a link interface system configured to interface with any one of a plurality of links with at least one of the plurality of links having a first diameter, another one of the plurality of links having a second diameter, with the first diameter being different than the second diameter. 
     The link interface system further including at least one pair of angled flanges that are configured to vary a clearance between angled flanges of the at least one pair of angle flanges from a first clearance to a second clearance, where the first clearance allows the angled flanges of the at least one pair of angled flanges to straddle a link with the first diameter and prevents the angled flanges of the at least one pair of angled flanges from straddling a link with the second diameter. 
     One general aspect includes a system for conducting subterranean operations including: an elevator configured to move a tubular, the elevator including: a housing defining a central bore configured to receive the tubular therein; a first latch including first and second jaws, with each of the first and second jaws being coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the first and second jaws are in the engaged position, engagement portions of the first and second jaws are positioned in the central bore; a second latch including third and fourth jaws, with each of the third and fourth jaws coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the third and fourth jaws are in the engaged position, engagement portions of the third and fourth jaws are positioned in the central bore; and an electronics enclosure within the housing, with the electronics enclosure configured to be ATEX certified or IECEx certified according to EX Zone 1 requirements. 
     Embodiments may include one or more of the following features. The system further including an electronics controller disposed in the enclosure and configured to control the elevator to handle the tubular. The system further including a hydraulic generator and an energy storage device, where the hydraulic generator generates electrical energy for operation of the elevator and stores a portion of the electrical energy in the energy storage device. The system where the storage device is a capacitive assembly or a battery, and where the storage device is disposed within the electronics enclosure. 
     One general aspect includes a system for conducting subterranean operations including: an elevator configured to move a tubular, the elevator including: a housing defining a central bore configured to receive the tubular therein; a first latch including first and second jaws, with each of the first and second jaws being coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the first and second jaws are in the engaged position, engagement portions of the first and second jaws are positioned in the central bore on opposite sides of, with respect to each other, a central axis of the central bore and define an opening of a first diameter; a second latch including third and fourth jaws, with each of the third and fourth jaws coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the third and fourth jaws are in the engaged position, engagement portions of the third and fourth jaws are positioned in the central bore on opposite sides of, with respect to each other, the central axis of the central bore and define an opening of a second diameter which is different than the first diameter; and an electronics controller disposed in an electronics enclosure within the housing and configured to control the elevator to handle the tubular. 
     Embodiments may include one or more of the following features. The system where the electronics enclosure is configured to be ATEX certified or IECEx certified according to EX Zone 1 requirements. 
     One general aspect includes a system for conducting subterranean operations including: an elevator configured to move a tubular, the elevator including: a housing defining a central bore configured to receive the tubular therein; a first latch including first and second jaws, with each of the first and second jaws being coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the first and second jaws are in the engaged position, engagement portions of the first and second jaws are configured to form a first frustoconically shaped portion positioned in the central bore and surrounding a central axis of the central bore, where the first frustoconically shaped portion defines an opening of a first diameter; and a second latch including third and fourth jaws, with each of the third and fourth jaws coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the third and fourth jaws are in the engaged position, engagement portions of the third and fourth jaws are configured to form a second frustoconically shaped portion positioned in the central bore and surrounding the central axis of the central bore, where the second frustoconically shaped portion defines an opening of a second diameter which is different than the first diameter, where the first frustoconically shaped portion includes a first gap between the first and second jaws when the first latch is in the engaged position, and where the second frustoconically shaped portion includes a second gap between the third and fourth jaws when the second latch is in the engaged position, and where the first and second gaps are parallel to the central axis, and the first gap is circumferentially offset, relative to the central axis, from the second gap. 
     Embodiments may include one or more of the following features. The system further including: a third latch including fifth and sixth jaws, with each of the fifth and sixth jaws coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the fifth and sixth jaws are configured to form a third frustoconically shaped portion positioned in the central bore and surrounding the central axis of the central bore, where the third frustoconically shaped portion defines an opening of a third diameter which is different than the first and second diameters, and a fourth latch including seventh and eighth jaws, with each of the seventh and eighth jaws coupled to the housing and configured to be moveable between an engaged position and a disengaged position, and when the seventh and eighth jaws are configured to form a fourth frustoconically shaped portion positioned in the central bore and surrounding the central axis of the central bore, where the fourth frustoconically shaped portion defines an opening of a fourth diameter which is different than the first, second, and third diameters, where the third frustoconically shaped portion includes a third gap between the fifth and sixth jaws when the third latch is in the engaged position, and where the fourth frustoconically shaped portion includes a fourth gap between the seventh and eighth jaws when the fourth latch is in the engaged position, and where the third and fourth gaps are parallel to the central axis, and the third gap is circumferentially offset, relative to the central axis, from the fourth gap. The system where the first and third gaps are circumferentially aligned relative to the central axis. The system where the second and fourth gaps are circumferentially aligned relative to the central axis. 
     Embodiment 1. A system for conducting subterranean operations comprising:
         an elevator configured to move a tubular, the elevator comprising:   a housing defining a central bore configured to receive the tubular therein, the central bore having a central axis; and   a link interface system configured to rotate the housing up to greater than 90 degrees about a housing axis.       

     Embodiment 2. The system of embodiment 1, wherein the link interface system is configured to engage a pair of links and rotate the housing relative to the links within a range of +/−4 degrees, +/−8 degrees, +/−12 degrees, +/−16 degrees, +/−20 degrees, +/−24 degrees, +/−28 degrees, +/−32 degrees, +/−36 degrees, +/−40 degrees, +/−44 degrees, +/−48 degrees, +/−52 degrees, +/−56 degrees, +/−60 degrees, +/−64 degrees, +/−68 degrees, +/−72 degrees, +/−76 degrees, +/−80 degrees, +/−84 degrees, +/−88 degrees, +/−92 degrees, +/−95 degrees, +/−96 degrees, +/−100 degrees, and +/−102 degrees relative to an axis of at least one of the links. 
     Embodiment 3. The system of embodiment 1, further comprising a hydraulic generator and an energy storage device, wherein the hydraulic generator generates electrical energy for operation of the elevator and stores a portion of the electrical energy in the energy storage device. 
     Embodiment 4. The system of embodiment 3, wherein the storage device is a capacitive assembly. 
     Embodiment 5. The system of embodiment 4, wherein the elevator is configured to be ATEX certified or IECEx certified according to EX Zone 1 requirements. 
     Embodiment 6. The system of embodiment 1, wherein the elevator, with the housing in a substantially horizontal orientation, is configured to support a tubular that weighs up to 1180 metric tons (˜ 1300 short tons), or up to 1134 metric tons (˜ 1250 short tons), or up to 1189 metric tons (˜ 1200 short tons), or up to 907 metric tons (˜ 1000 short tons), or up to 680 metric tons (˜ 750 short tons), or up to 454 metric tons (˜ 500 short tons), or up to 318 metric tons (˜ 350 short tons), or up to 227 metric tons (˜ 250 short tons). 
     Embodiment 7. The system of embodiment 1, wherein the elevator is configured to manipulate the tubular between horizontal and vertical orientations, and wherein the tubular weighs up to 3000 kg (˜ 3 short tons). 
     Embodiment 8. The system of embodiment 1, wherein the elevator further comprises one or more sensors disposed between a spacer ring and the housing, and a controller, wherein the sensors detect a force applied between the spacer ring and the housing, and the controller is configured to determine a weight of the tubular supported by the elevator. 
     Embodiment 9. The system of embodiment 1, further comprising a top drive coupled to the elevator housing via a pair of links, with each of the links rotationally attached to the top drive at one end and rotationally attached to the housing at an opposite end. 
     Embodiment 10. The system of embodiment 1, wherein the housing axis is perpendicular to the central axis, wherein the link interface system comprises a rotary actuator having a body and a drive shaft, with the body fixedly attached to the housing and the drive shaft coupled to a link interface that is rotationally attached to the housing, and wherein when the drive shaft is rotated by the rotary actuator, the link interface is rotated about the housing axis. 
     Embodiment 11. The system of embodiment 10, further comprising a sensor that detects an angular position of the housing relative to the link interface, wherein the sensor is disposed within a sealed chamber of the housing that prevents a portion of environmental fluids from entering the sealed chamber during the subterranean operations. 
     Embodiment 12. The system of embodiment 1, further comprising a rotary actuator coupled to each pair of jaws of the elevator and a sensor coupled to each rotary actuator, wherein the sensor detects an angular position of the rotary actuator, and a controller is configured to determine whether one or more of the jaws are in an engaged or disengaged position. 
     Embodiment 13. The system of embodiment 1, further comprising:
         a rig;   a top drive supported by the rig;   a pair of links rotatably attached to the top drive; and   the elevator rotatably attached to the pair of links.       

     Embodiment 14. The system of embodiment 1, wherein the link interface system is configured to interface with any one of a plurality of links with at least one of the plurality of links having a first diameter, another one of the plurality of links having a second diameter, and the first diameter is different than the second diameter. 
     Embodiment 15. The system of embodiment 14, wherein the link interface system comprises at least one pair of angled flanges that are configured to vary a clearance between angled flanges of the at least one pair of angle flanges from a first clearance to a second clearance, wherein the first clearance allows the angled flanges of the at least one pair of angled flanges to straddle a link with the first diameter and prevents the angled flanges of the at least one pair of angled flanges from straddling a link with the second diameter. 
     Embodiment 16. A system for conducting subterranean operations comprising:
         an elevator configured to move a tubular, the elevator comprising:   a housing defining a central bore configured to receive the tubular therein;   a first latch comprising first and second jaws, with each of the first and second jaws being coupled to the housing and configured to be moveable between an engaged position and a disengaged position; and   an electronics controller disposed in an electronics enclosure within the housing and configured to control the elevator to handle the tubular.       

     Embodiment 17. The system of embodiment 16, wherein the electronics enclosure is configured to be ATEX certified or IECEx certified according to EX Zone 1 requirements. 
     Embodiment 18. The system of embodiment 17, further comprising an electronics controller disposed in the enclosure and configured to control the elevator to handle the tubular. 
     Embodiment 19. The system of embodiment 17, further comprising a hydraulic generator and an energy storage device, wherein the hydraulic generator generates electrical energy for operation of the elevator and stores a portion of the electrical energy in the energy storage device. 
     Embodiment 20. The system of embodiment 19, wherein the storage device is a capacitive assembly or a battery, and wherein the storage device is disposed within the electronics enclosure. 
     While the present disclosure may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and tables and have been described in detail herein. However, it should be understood that the embodiments are not intended to be limited to the particular forms disclosed. Rather, the disclosure is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure as defined by the following appended claims. Further, although individual embodiments are discussed herein, the disclosure is intended to cover all combinations of these embodiments.