Patent Publication Number: US-11642691-B2

Title: Automatic pipe doping apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional application that claims priority to U.S. non-provisional application 16/175,259 that was filed Oct. 30, 2018, claims priority from U.S. provisional application No. 62/581,246, filed Nov. 3, 2017, which is incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD/FIELD OF THE DISCLOSURE 
     The present disclosure relates to the cleaning and application of lubricant to pin ends of tubular members. 
     BACKGROUND OF THE DISCLOSURE 
     The exploration and production of hydrocarbons requires the use of drilling systems that include tubulars such as drill pipes, casings, and other threadedly connected elements used in the well structures. Typically, a string of drill pipes coupled end-to-end and referred to as a drill string is used to form a wellbore. These tubulars are normally assembled in groups of two or more commonly known as “stands” to be vertically stored in the derrick or mast. 
     On a drilling rig, the drill string may be assembled in the derrick or mast. The drill string may be run downhole and into the wellbore. The drill string may be used to transmit rotational power to the drill bit located at the lower end of the drill string. The drill string may also be used to transmit drilling fluid, commonly known as mud, down through the internal bore in the drill string. The mud exits at or near the drill bit and then circulates back up the well annulus between the drill string and the well bore. The drill pipe string may also run casing, a liner, or a landing string downhole. The drill string may also be used for work-over activity of a hydrocarbon well. 
     The drill string is comprised of tubulars threaded and connected together by the threaded ends of each tubular. A joint or segment of a drill pipe may vary in length. A joint or segment of drill pipe is comprised of a female connection, known as the “box” and a male section known as the “pin”. The box end is internally threaded and adapted to receive the pin end member of another drill pipe joint, which has external threads. A drill string is assembled by connecting the multiple joints and tightening each threaded connection to a predetermined torque value. Typically, power tongs or automated roughnecks are used to transmit sufficient torque to the pipe joints to ensure that the pin is securely tightened to the box. The amount of torque required to securely tighten the tubulars is known as make-up torque. Properly torqued connections are crucial to drill string integrity. Insufficient torque may result in failure of the threaded connection and excessive torque could stretch or burst the box member or crack or break the pin member. 
     A blend of lubricating grease and fine metallic particles known as “pipe dope” is typically applied to each threaded connection. Pipe dope has several functions, including maintaining a consistent coefficient of friction so that predictable preloads result from the make-up torque, preventing galling in rotary shouldered connections, promoting sealing between each pin and box, and protecting thread surfaces from corrosion. 
     Typically, rig personnel manually apply pipe dope to the threaded pipe connections on the rig floor. Manual pipe doping is performed using bristle or mop style brushes dipped into containers of lubricating compound on the rig floor, then manually applied to the pin end of the tubular. An automated rig floor precludes this manual method. Further, this operation may be time consuming and dangerous for the rig personnel. 
     SUMMARY 
     The present disclosure provides an apparatus and method for applying pipe dope to the pin or box end of a tubular. In some embodiments, a pipe doping apparatus consistent with this disclosure comprises a rotating bucket assembly including a base and a rotating bucket supported on the base and having an inside volume, a rotary actuator, the rotary actuator mechanically coupled to the rotating bucket, a cleaning unit, the cleaning unit including at least one high pressure cleaning fluid nozzle inside the bucket, a drying unit, including at least one gas outlet inside the bucket, and, a lubricating unit, the lubricating unit having at least one retractable lubricant applicator inside the bucket. The apparatus may also include various sensors, including but not limited to fluid level sensors, pressure sensors, position sensors, rotation sensors, proximity sensors, timers, and contact sensors, each of which may provide input to the controller. 
     In some embodiments, a pipe doping apparatus may comprise a bucket assembly including a base and a bucket supported on the base and having an inside volume, a cleaning unit having at least one cleaning fluid outlet inside the bucket, a drying unit having at least one gas outlet inside the bucket, a lubricating unit having at least one retractable applicator inside the bucket, and a source of torque configured to rotate at least one of the bucket, the cleaning unit, the drying unit, and the lubricating unit relative to the base. 
     In some embodiments, the source of torque may be a fluid jet in at least one of the cleaning unit and the drying unit. At least one lubricant applicator may be retractable and may be actuated between a retracted position and an extended position by centripetal force. In some embodiments, at least one of the applicators is extendable and retractable by active (pneumatic, hydraulic, electric) or passive (centripetal) means. 
     The pipe doping apparatus may further include a positioning assembly supporting the base and the rotary bucket assembly and a controller connected to and controlling each of: the positioning assembly, the cleaning unit, the drying unit, and the lubricating unit. In some embodiments, the pipe doping apparatus may further include a bucket rotation sensor and the bucket may include a drain. In some embodiments, the pipe doping apparatus may further include an additional lubricating unit mounted on one of the bucket, the base, or the positioning assembly and extendable so as to apply lubricant to a top drive pin. 
     The pipe doping apparatus may further include a cleaning fluid reservoir and pump in fluid communication with the high pressure cleaning fluid nozzle. The drying unit gas outlet may be an air knife, which may be in fluid communication with a blower or air compressor. 
     A lubricant reservoir and pump may be in fluid communication with the retractable lubricant applicator and the retractable lubricant applicator may comprise an applicator selected from the group consisting of spatula-type applicators, bristle brushes, mop brushes, foam brushes, and roller brushes. The retractable lubricant applicator may be coupled to a pneumatic actuator that may be adapted to move the retractable lubricant applicator from a retracted position to an extended position. 
     A method of applying lubrication to a pin end of a tubular in accordance with the present disclosure comprises a) providing a pipe doping apparatus, the pipe doping apparatus comprising a rotating bucket assembly, the rotating bucket assembly including a base and a bucket supported on the base and having an inside volume, a rotary actuator, the rotary actuator mechanically coupled to the rotating bucket, a cleaning unit, the cleaning unit including at least one high pressure cleaning fluid nozzle extending into the inside volume, a drying unit, including at least one gas outlet extending into the inside volume, and a lubricating unit, the lubricating unit having at least one retractable lubricant applicator in the inside volume, b) positioning the pin end of the tubular within the rotating bucket assembly, c) rotating the rotating bucket assembly, and d) removing the pin end of the tubular from the rotating bucket assembly. Step c) may comprise, while rotating the rotating bucket assembly, c1) cleaning the pin end of the tubular, for example by supplying fluid through one or more high pressure fluid nozzles, c2) drying the pin end of the tubular, for example by supplying gas through the dryer nozzles, and c3) lubricating the pin end of the tubular, for example by supplying pipe dope to the lubricant applicators. 
     The pipe doping apparatus may include a positioning assembly supporting the base and the rotary bucket assembly and step b) may comprise using the positioning assembly to move the rotary bucket assembly such that the pin end of the tubular is received in the bucket. 
     Step c3) may include advancing the retractable lubricant applicator toward the pin end of the tubular, contacting the pin end of the tubular with the retractable lubricant applicator, and retracting the retractable lubricant applicator away from the pin end of the tubular and step c2) may comprise directing air through an air knife to the pin end of a tubular. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present disclosure is best understood from the following detailed description when read with the accompanying figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion. Also, for the sake of clarity, portions of the assembly may be hidden from view or cut-away in certain figures. 
         FIG.  1    is a partially exploded and partially schematic diagram of a pipe doping system consistent with at least one embodiment of the present disclosure. 
         FIG.  2    is a top view of part of a pipe doping apparatus consistent with embodiments of the present disclosure. 
         FIG.  3    is a cutaway side view showing a cleaning unit of a pipe doping apparatus consistent with embodiments of the present disclosure. 
         FIG.  4    is an enlarged side view showing a drying unit of a pipe doping apparatus consistent with embodiments of the present disclosure. 
         FIGS.  5  and  6    are each a cutaway view of a lubricating unit of a pipe doping apparatus consistent with elements of one embodiment of the present disclosure in a retracted and extended position, respectively. 
         FIG.  7    is a perspective view of a positioning assembly of a pipe doping apparatus consistent with embodiments of the present disclosure. 
         FIGS.  8  and  9    are perspective and side views, respectively, of an additional component of a pipe doping apparatus consistent with embodiments of the present disclosure. 
         FIG.  10    is a top view of the additional component of  FIGS.  8  and  9    mounted on a pipe doping apparatus according to one embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     It is to be understood that the following disclosure provides many different embodiments, or examples, for implementing different features of various embodiments. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. 
       FIG.  1    depicts pipe doping system  100  for applying pipe dope (lubricant) to one end of a tubular. Pipe doping system  100  may include a rotating bucket assembly  106  comprising a rotating bucket  107 , a removable guard  113 , and a base  102 , a fluid supply system  109 , an optional positioning assembly  600  (shown in  FIG.  7   ), and a controller  128 . Each is described in more detail below. When the system is in use, guard  113  fits over bucket  107  and rests on base  102 . Bucket  107  and guard  113  are configured to receive therein the pin end  112  of a length of pipe  110  (shown in phantom). 
     As shown in  FIG.  1   , fluid supply system  109  may include a cleaning fluid reservoir  116  in fluid communication with a cleaning fluid pump  124 , an drying gas reservoir  410  in fluid communication with drying gas pump  404 , which may be an air pump or compressor, and a lubricant reservoir  118  in fluid communication with a lubricant pump  119 . In some embodiments, fluid reservoir  116 , drying gas reservoir  410 , and lubricant reservoir  118  may be fluidly connected to rotating bucket assembly  106  through fluid supply lines  122   a - c  respectively, with flow therethrough controlled by valves  117   a - c , respectively. In some embodiments, the relative positions of each reservoir and pump may be interchanged. 
     Referring now to  FIGS.  1 - 2   , rotating bucket  107  of rotating bucket assembly  106  includes a bucket wall  202  with an inner surface  204 , an open top  114 , and plurality of drain holes  209  that are fluidly connected to a drain  130  ( FIG.  1   ) for drainage of residual cleaning fluid and lubricant. In certain embodiments, rotating bucket assembly  106  may include a rotation sensor (not shown) for determining whether rotating bucket assembly  106  is rotating relative to base  102 . As best shown in  FIG.  2   , rotating bucket assembly  106  may include one or more guides  108  to protect the bucket internals from inadvertent impact with the tubular. If desired, an additional guide, not shown, may be provided inside the bucket. The additional guide may be coaxial with the bucket and may be conical or frustoconical, so that the tubular slides over the additional guide as it enters the bucket and may be guided by the additional guide to a desired position within the bucket. As described below, rotating bucket  107  may contain a plurality of sub-assemblies including a cleaning unit  206 , a drying unit  208 , and a lubricating unit  210 , each of which may be mounted on the floor or inside wall of bucket  107  so as to rotate with rotating bucket  107 . 
     Referring now to  FIG.  3   , cleaning unit  206  may include one or more high pressure fluid jets  300  that are in fluid communication with fluid reservoir  116  and cleaning fluid pump  124 . In embodiments in which cleaning unit  206  includes a plurality of high pressure fluid jets  300 , high pressure fluid jets  300  may be arranged around the circumference of bucket wall inner surface  204 , vertically along bucket wall inner surface  204  (as shown), or otherwise as desired. Each high pressure fluid jet  300  may include a high pressure nozzle  302 . It will be understood that while cleaning unit  206  is shown wholly within bucket  107 , cleaning unit  206  may alternatively be mounted wholly or partially outside of bucket  107 , with jets  300  extending through bucket wall  202  and with nozzles  302  positioned at a desired location within bucket  107 . 
     Referring now to  FIG.  4   , drying unit  208  may include one or more air outlets  408  that are in fluid communication with drying gas reservoir  410 . In certain embodiments, drying unit  208  may be a high pressure air dryer. In some embodiments, air outlet  408  may be configured to provide an “air blade” or “air knife.” In other embodiments, air outlet  408  may comprise an array of air nozzles. Air outlet  408  may deliver pressurized air to the surface of pin end  112 , which may serve to dry pin end  112 . Drying gas pump  404  ( FIG.  1   ) may be a blower or air compressor. 
     Referring now to  FIGS.  5  and  6   , lubricating unit  210  may include one or more retractable lubricant applicators  500  that are in fluid communication with lubricant reservoir  118  and lubricant pump  119  via line  122   c  and a fluid passageway (not shown) that extends through each lubricating unit. One or more retractable lubricant applicators  500  may each include an applicator head  512  extending therefrom. Each retractable lubricant applicator  500  may be, for example and without limitation, a spatula-type applicator, a mop-type brush, a bristle brush, a foam brush, a roller brush, or any other device suitable for applying pipe dope. One or more lubricant applicator  500  may be formed from a durable material that is generally nonreactive to the chemicals in the pipe dope and other fluids typically encountered during operations. In some embodiments, lubricant may be delivered to each applicator head  512  through a grease passage  516  ( FIG.  6   ). 
     In embodiments in which there are multiple retractable lubricant applicators  500 , the brush heads may be arranged so that their configuration corresponds to the taper of pin end  112 . 
     Lubricating unit  210  may also include one or more pneumatic actuation system  502 . Pneumatic actuation system  502  may include a pneumatic cylinder  506  defining a chamber, a piston (not shown) received in the chamber, and, optionally, a spring  510 . Retractable lubricant applicators  500  may be mechanically coupled to the piston of pneumatic cylinder  506  such that when the chamber of pneumatic cylinder  506  is filled with pressurized air, spring  510  is compressed, thereby shifting applicator heads  512  toward bucket wall inner surface  204  and out of contact with pin end  112 . When pneumatic cylinder  506  is vented or pressurized on its other side, spring  510  extends (if present), the piston is pushed back through pneumatic cylinder  506 , thereby shifting applicator heads  512  away from bucket wall  202  and toward pin end  112  of tubular  110 . Thus, lubricant applicators  500  can be controllably retracted by selectively pressurizing pneumatic actuation system  502 . 
     Lubricant applicators  500  need not be co-supported. In alternative embodiments, a separate pneumatic actuation system  502  may be provided for each retractable lubricant applicator  500 . In some embodiments, each of retractable lubricant applicators  500  may be coupled to a divider valve assembly that controllably divides flow of lubricant among retractable lubricant applicators  500  and/or between multiple lubricating units  210 . 
     In some embodiments, lubricating unit  210  includes a centripetal actuation system that uses the inertia of the rotating components to move retractable lubricant applicators  500  from a retracted to an extended position. By way of example, a lubricant applicator may be pivotably mounted and a relatively heavier weight may be mechanically coupled thereto such that when lubricating unit  210  rotates around the bucket axis, the weight will tend to move outward, away from the bucket axis, causing the lubricant applicator to move toward the bucket axis. In some instances, the lubricant applicator or lubricant thereon may move far enough toward the bucket axis as to come into contact with the end of a tubular in the bucket. If desired, the applicator may be designed such that friction may slow rotation of the lubricating unit relative to the pipe, allowing the weight to return to its original position and causing the lubricant applicator to retract. 
     Referring again to  FIG.  1   , in certain embodiments, pipe doping apparatus  100  may include a rotary actuator  104  mechanically connected between base  102  and rotating bucket assembly  106 . Rotary actuator  104  is configured to rotate rotating bucket assembly  106  about the center axis of rotating bucket  107  relative to base  102 . Rotary actuator  104  may be any mechanism for providing a rotational force, or torque. By way of example, rotary actuator  104  may be a motor and may be driven by any suitable means, including hydraulic, electric, or pneumatic power sources. Rotary actuator  104  may drive bucket  107  directly or by means of gears, belts, or other power transmission means. In some alternative embodiments, bucket  107  may not rotate relative to the base and instead one or more of the sub-assemblies including cleaning unit  206 , drying unit  208 , and lubricating unit  210  may rotate relative to the bucket and/or the pipe. In these embodiments, bucket  107  may or may not rotate. 
     Alternatively or in addition, rotation of one or more components relative to pipe  110  may be driven by fluid momentum change from air or water jets. By way of example, at least one of the cleaning unit and the drying unit may include outlet jets that are oriented other than directly at the tool axis, such that flow of fluid through the outlet jets imparts a torque or rotational force to the jet and its support. If unit is able to rotate with respect to the base, this force will cause it to rotate. In still other embodiments, the rotary actuator may be mechanically connected between base  102  and a positioning assembly such as is described below, between bucket assembly  106  and a positioning assembly, or between one or more of the sub-assemblies and a positioning assembly. 
     In some embodiments, a slewing bearing  131  ( FIG.  3   ) mechanically couples rotating bucket assembly  106  to base  102 . A rotary coupling  111  enables fluid communication between rotating bucket assembly  106  and base  102 . Rotary coupling  111  supplies cleaning fluid, drying fluid, and lubricant from lines  122   a - c  to cleaning unit  206 , drying unit  208 , and a lubricating unit  210 , respectively. Rotary coupling  111  may include a stationary rotator coupling affixed to base  102  and a rotating rotator coupling affixed to rotating bucket assembly  106 . Rotating bucket assembly  106  may be positioned on top of base  102 . 
     In certain embodiments, pipe doping apparatus  100  may be positioned relative to pipe  110  using a positioning assembly  600 , illustrated in  FIG.  7   . Positioning assembly  600  may include a hinged arm assembly  603 , a support frame  604 , and at least one positioning actuator  602  configured to move hinged arm assembly  603  relative to support frame  604 . In some embodiments, arm assembly  603  and frame  604  can each extend and retract, with support frame  604  providing vertical movement and arm assembly  603  providing lateral movement. In some embodiments, there may be one positioning actuator to provide vertical motion of frame  604  and a second positioning actuator to provide lateral movement and or rotation of arm assembly  603 . Movement of either arm assembly  603  and/or frame  604  causes rotating bucket assembly  106  to move. Frame  604  may be mechanically coupled to any stationary part of a drilling rig. Each positioning actuator may comprise a hydraulic, pneumatic, or electric actuator and may be rotary or linear in form. 
     In certain embodiments, an additional lubricating unit  212  may be included in pipe doping system  100 . As shown in  FIG.  8   , additional lubricating unit  212  may include a housing  219  and one or more lubricant applicators  520  that may be in fluid communication with lubricant reservoir  118  and lubricant pump  119  ( FIG.  1   ). Lubricant applicators  520  may each include an applicator head  522  extending therefrom. Like retractable lubricant applicators  500 , each lubricant applicator  520  may be, for example and without limitation, a spatula-type applicator, a mop-type brush, a bristle brush, a foam brush, a roller brush, or any other device suitable for applying pipe dope and may be formed from a durable material that is generally nonreactive to the chemicals in the pipe dope and other fluids typically encountered during operations. If desired, lubricant applicators  520  may be supported on one or more telescoping arm  524  that allows the lubricant applicator(s) to be retracted into housing  219 . 
     Additional lubricating unit  212  may be mounted on rotating bucket  107 , on base  102 , on positioning assembly  600 , or may be mounted on an additional or separate positioning assembly (not shown) that is itself mounted on rotating bucket  107 , on base  102 , on positioning assembly  600 . By way of example only, as illustrated in  FIGS.  8 - 10   , additional lubricating unit  212  may include a mounting bracket  214  that can be attached to bucket guard  113  ( FIG.  1   ). 
     Additional lubricating unit  212  may be configured to apply lubricant to the pin end of a top drive assembly. The pin of a top drive tends to be less accessible than a tubular pin end and the components of additional lubricating unit  212  may be sized to fit between or around obstacles so as to position lubricant applicators  520  close enough to apply lubricant to the top drive pin. The position and operation of rotation of additional lubricating unit  212  may be controlled by controller  128 . 
     As indicated by the directional arrows in  FIG.  1   , in some embodiments, it may be desired to move the rotating bucket assembly  106  toward the pin end  112 , in some embodiments it may be desired to move the pin end  112  into the rotating bucket assembly  106 , and in some embodiments it may be desired to move both pin end  112  and rotating bucket assembly  106  jointly. Further, it will be understood that neither pin end  112  nor rotating bucket assembly  106  need be oriented as illustrated: by way of example, each could have a horizontal rather than a vertical axis. Optionally, one or more sensors (not shown) may be configured to sense when tubular  110  is in the desired position within bucket  107  and to communicate that information to controller  128 . 
     Still further, a sensor (not shown) may be used to actuate a cleaning, drying, and doping cycle when a tubular has reached a suitable position within bucket  107 . The sensor may be a mechanical (pressure) sensor, acoustic sensor, photo-sensor, or other suitable sensor capable of detecting the presence or location of pin end  112  and transmitting an actuation signal to controller  128 . 
     In certain embodiments, the flow of one or more of cleaning fluid, air, and lubricant may be controlled by one or more control valves. In some embodiments, as shown in  FIG.  1   , flow from cleaning fluid reservoir  116  is controlled by control valve  117   a , flow of air from drying gas reservoir  410  is controlled by control valve  117   b , and flow of lubricant from lubricant reservoir  118  is controlled by control valve  117   c . Control valves  117   a - c  may each be actuated by controller  128 , which is in data communication with control valves  117   a - c . In some embodiments, the flow of one or more of cleaning fluid, air, and lubricant may be controlled by the selective actuation of cleaning fluid pump  124 , drying gas pump  404 , and lubricant pump  119  respectively. In some such embodiments, fluid pump  124 , drying gas pump  404 , and lubricant pump  119  may also be controlled by controller  128 . 
     Referring again to  FIG.  1   , fluid reservoir  116  may hold a cleaning fluid for use in cleaning unit  206 . In a non-limiting example, the cleaning fluid is water. Fluid in fluid reservoir  116  may be transferred to pipe doping assembly  100  via cleaning fluid pump  124 . 
     Drying gas reservoir  410  may hold drying gas for use in drying unit  208 . In a non-limiting example, the drying gas is air. Gas in drying gas reservoir  410  may be transferred to pipe doping assembly  100  via drying gas pump  404 . 
     Lubricant reservoir  118  may hold lubricant fluid for use in lubricating unit  210 . Lubricant fluid may be pipe dope, grease, or any lubricating material for sealing and lubricating a tubular connection, herein referred to generally as “lubricant.” In some embodiments, the lubricant may be selected based on one or more desired material properties including but not limited to consistency, viscosity, and wetting properties. Lubricant from lubricant reservoir  118  may be transferred to pipe doping assembly  100  via lubricant pump  119 . 
     Operation 
     In an exemplary method of operation, when present, positioning assembly  600  may position pipe doping apparatus  100  for cleaning and lubricating pin end  112  of tubular  110 . Such positioning may include positioning rotating bucket  107  such that pin end  112  of tubular  110  is received in rotating bucket  107  through open top  114 . Optional sensors may sense when tubular  110  is in the desired position within bucket  107  and communicate that information to controller  128 . Once pin end  112  of tubular  110  is received in rotating bucket  107 , rotating bucket  107  and/or the components therein may be rotated using rotary actuator  104 . Rotation of rotating bucket  107  may be continuous or intermittent while pin end  112  of tubular  110  is within rotating bucket  107 . Tubular  110  may remain stationary. The rate and duration of rotation of rotating bucket  107  may be controlled by controller  128 . 
     Cleaning fluid may be pumped using fluid pump  124  from fluid reservoir  116 . When present, control valve  117   a  may be opened to allow cleaning fluid to flow through to rotary coupling  111  to one or more high pressure nozzles  302  via one or more cleaning fluid supply lines  122   a . Cleaning unit  206  may clean pin end  112  of tubular  110  by spraying pressurized cleaning fluid onto tubular pin end  112 . Cleaning unit  206  may rotate around tubular  110  as rotating bucket assembly  106  rotates, thereby cleaning the entire circumference of pin end  112 . Cleaning unit  206  may deliver a predetermined amount of cleaning fluid to pin end  112  or operate for a predetermined period of time. Upon completion of a cleaning cycle, controller  128  may close control valve  117   a  (if present) and fluid pump  124  may cease operation. Residual cleaning fluid may drain from rotating bucket assembly  106  through drain  130 . 
     After the cleaning cycle is complete, drying unit  208  may be activated by controller  128  to dry pin end  112  prior to lubricant application. Controller  128  may open control valve  117   b , allowing pressurized air or other drying fluid to enter rotating bucket assembly  106  through rotary coupling  111 . Drying unit  208  may remove cleaning fluid from pin end  112  by delivering pressurized air to surface of pin end  112 . Drying unit  208  may rotate around tubular  110  as rotating bucket assembly  106  rotates, thereby drying the entire circumference of pin end  112 . Drying unit  208  may operate for a predetermined amount of time or deliver a predetermined amount of air to pin end  112 . After completion of the drying operation, controller  128  may close control valve  117   b  (if present). 
     After the drying operation is completed, lubricating units  210  may engage pin end  112 . Pneumatic actuator  502  may extend one or more retractable lubricant applicators  500  from a retracted position to an extended position, as described above. Lubricant may be pumped by lubricant pump  119  from lubricant reservoir  118  through control valve  117   c  (if present) and rotary coupling  111  to the divider valve assembly (if present). The divider valve assembly may deliver a metered volume of lubricant to one or more retractable lubricant applicators  500 . Each applicator head  512  applies lubricant to the surface of pin end  112  of tubular  110 . Lubricating units  210  may rotate around tubular  110  as rotating bucket assembly  106  rotates thereby lubricating the entire circumference of pin end  112 . Lubricating unit  210  may operate for a predetermined amount of time or deliver a predetermined amount of lubricant to pin end  112 . 
     After completion of the lubricating operation, pneumatic actuator  502  may retract one or more retractable lubricant applicators  500  from an extended position to a retracted position, as described above. Controller  128  may close control valve  117   c  and lubricant pump  119  may cease operation. Controller  128  may then cease rotation of rotating bucket assembly  106 . Residual lubricant may exit rotating bucket  107  through drain  130 . 
     In other embodiments, the flow of fluid from the cleaning and/or drying unit may be sufficient to cause rotation of the components of the device relative to the pipe. In still further embodiments, rotation of the lubricating unit may be sufficient to actuate retractable lubricant applicators  500  from a retracted position to an extended position and cessation of rotation may allow them to fall back to a retracted position. 
     In some embodiments, the system may include one or more sensors for sensing the amount and distribution of cleaning fluid, drying fluid and lubricating compound applied to tubular  110 . 
     Upon completion of lubrication of tubular  110 , positioning assembly  600  may lower rotating bucket assembly  106 , thereby removing and/or disengaging rotating bucket assembly from tubular  110 . In some embodiments, the entire process takes place while the auto-doper system is rotating. If power is lost, the controller and control valves may fail to a safe mode where no water, air, or lubrication is supplied or pumped. 
     In some embodiments, additional lubricating unit  212  may be used to apply lubricant to a top drive pin as part of tripping operations in which the top drive assembles or disassembles the joints of a drill string. 
     The present automatic pipe doping system reduces or eliminates the need for rig personnel to be present on the rig floor, thereby removing them from a safety-intensive zone. Because bucket  107  rotates about the drill pipe connection, it is relatively easy for a pipe handling machine to insert a tubular for the cleaning and lubrication. The lubricant applicators in the present invention can be selected to apply lubricating compound to the pipe threads in the conventional manner or in another desired mode, thereby achieving a desired result. For example, if the conventional-style brushes are selected, the same even distribution of lubrication compound will result as with the current manual method. Alternatively, a special pattern of brushes could be selected to provide a specific lubricant pattern on the pipe. Similarly, the amount of cleaning fluid, drying fluid, and lubricant applied to tubular  110  may be adjusted on the fly by controller  128  so as to respond to varying conditions. 
     The present automatic pipe doping system may also reduce or eliminate the need for motors to move the various components of the system in order to accomplish the desired steps. By way of example, rotation of the components may be caused by fluid jets and actuation of the lubricant applicator(s) may be caused by centripetal action. By eliminating unneeded motors, the present system can be safer and less likely to fail. 
     The foregoing outlines features of several embodiments so that a person of ordinary skill in the art may better understand the aspects of the present disclosure. Such features may be replaced by any one of numerous equivalent alternatives, only some of which are disclosed herein. One of ordinary skill in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. One of ordinary skill in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure.