Patent Publication Number: US-2017363232-A1

Title: Torque Style Union for Joining Conduit and Tool for Use Therewith

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present invention claims priority from a provisional application, Ser. No. 62/352,250, filed Jun. 20, 2016, entitled “Hammerless Union Connection”, by the same inventor. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates generally to conduit unions for connecting sections of conduit and to a tool for attaching and removing such unions from conduit connections. 
     Description of the Prior Art 
     Threaded unions, sometimes referred to as “hammer unions”, are used in a variety of industries. In the area of petroleum exploration and production, they are used to join conduits together, for example, conduits containing high-pressure fluids, such as the pipelines used to convey drilling mud, fracturing fluids, and oil and gas produced as a result of drilling activities. Hammer unions have generally been considered to be economical, simple, reliable and robust. A typical example of the traditional hammer union is the WECO™ brand of hammer unions available from FMC Technologies of Houston, Tex. This particular hammer union is merely used to illustrate an example of the type of devices under consideration, there being many other similar commercially available devices at the present time. Typically, hammer unions are used in more temporary situations, for example, for joining together sections of pipe used for pumping fracturing fluids into a well bore under high pressure. However, hammer unions may also be used in certain long-term applications for their ease of make-up and break-out, especially, for example, for equipment that may need to be replaced quickly and efficiently (e.g., rotary hoses for conveying drilling mud between a stand pipe manifold and a rotary swivel or top drive, or components of a choke manifold, such as valves, chokes and spools which may fail unexpectedly due to erosive flows, etc). 
     Inevitably, in industrial piping systems, plumbing and flow lines systems, the lugs or tangs of the “wing nut” portion of the hammer union will receive variable degrees of visible external damage because of the repeated blows of a sledgehammer that is used against the hammer union to tighten the union. A wing nut with one or more deformed lugs may not be reliably mated with another piece of piping equipment. The piping equipment, however, would generally still be usable if the wing nut is replaced. Currently, when a wing nut becomes deformed due to damaged or deformed lugs, the end of the wing nut pipe segment on which the wing nut is installed is cut off, the deformed wing nut is replaced with a new wing nut, and the pipe is machined and welded together. Unfortunately, this repair approach often has quality problems. These quality problems lead to safety issues. A misaligned wing nut on a hammer union joint may hold pressure for a period of time, but may ultimately fail as the pressure pushes against the joint. 
     An attempted field repair of a wing nut using common cutting and welding techniques creates a significant risk for misaligned or poorly welded joints. In typical field situations, there may be few or no field personnel qualified to perform the highly skilled welding and machining operations required for a safe repair. Since field repairs may result in significant down time, there is also an economic impact when removing a pipe section to replace a deformed wing nut. In manufacturing and drilling operations, down time directly impacts a company&#39;s cost of operations. 
     The primary reason for wing nut damage is repeated blows from a sledgehammer during the act of tightening the wing nut. As mentioned, connections are made up and broken down by causing the wing nut to turn by repeated blows of heavy hammers, such as sledgehammers with hardened steel heads weighing as much as 20 lbs. that are wielded by hand. This can create a situation where the powerful sledgehammer swings are not correctly directed to the wing nut lugs or tangs, as the user may miss-swing or partially deflect the wing nut tang on a particular swing. This can result in strikes to a lower extremity of the sledgehammer user and can cause potential severe injury to the user. Additionally, the relatively small tangs of the union wing nuts can cause the sledgehammer user to miss the hammer tangs and cause strikes to undesired external surfaces, such as the conduits or surrounding piping. Furthermore, repeated striking of the lugs, tangs or the like of the wing nut can result in metal fatigue, causing the lug to break off and effectively become a dangerous missile. 
     The use of sledgehammers is among the top causes of job injuries in the oilfield industry. Swinging a hammer or striking or dropping a hammer against one&#39;s self or others can cause muscle strains, pinch points, or other physical harm to a worker. Further, conduit, hose, or pipe unions are often assembled or broken down in areas or locations where flammable fumes may permeate the air. Striking the surface of a wing or lug of a union connector, may create sparks which could ignite such flammable fumes creating the potential for explosions and fires that may expose the worker to severe burns or even death as well as extensive property damage to the location. 
     Another disadvantage of the standard hammer union is the fact that when making such connections with these hammers it is generally impossible to achieve or verify the torque required or desired for effectively mating the components of the threaded portions of the hammer unions. The general forceful over-tightening of the conduit union can inherently create a situation where the user is unable to fully disconnect the connected conduit because of the over-rated force applied during the assembly. This can make the fully-assembled conduit union nearly impossible to remove or to disassemble for common replacement or repositioning purposes. There is also the general lack of quality control considerations, since the user really has no definite idea how much torque has been applied to the connection at hand. 
     One alternative used in the past for the hammer union was the use of manually operable tongs. These tongs typically have a handle and jaw members that are used grip and turn a nut, swivel, or another threaded connection component of the threaded union. The torque or moment force used to turn the threaded connection components of the threaded union to make up or break out of the threaded joint is created by the force applied to the jaws by tong handle. When the union connection joint is completed, the jaws of the tongs are opened to permit their removal from around the conduit pipe and the threaded union creating the connection joint. Often the moment force or torque applied to the threaded union by the tong jaws is not sufficient to adequately seal the conduit ends together which may result in leaks or cause the conduit to decouple under pressure. Alternatively, the manual tongs may overtighten the connection. Again, the amount of torque applied by the tongs was not typically tracked or recorded. 
     Consequently, a need exists for an improved fluid conduit union connection and method that will reliably make-up and break-out such a union connection, reduce conduit sealing problems, and reduce the risk of harm for the workers and the risk of damage to the work site location and equipment. The use of such a device will correspondingly enhance worksite safety and reduce the cost and expenses typically associated with the conduit connecting devices and methods currently 
     A need also exists for an improved conduit union and associated make-up and break-out tool which will have improved capabilities for monitoring and recording the torque applied to each union connection in the pipe line. 
     Additional objects, features and advantages will be apparent in the written description which follows. 
     SUMMARY OF THE INVENTION 
     In one aspect, the present invention provides a torque style, or “hammerless” union for connecting fluid conduits. 
     In a further aspect, the present invention provides a union nut and wrench system for use in a hammerless union for connecting first and second conduits. 
     In a further aspect, the present invention provides a torque style union for connecting first and second conduits wherein the torque applied to make-up the connection can be determined. 
     In accordance with the above objects, a torque operable union nut is provided, comprising:
         a union nut body having an upper peripheral planar face, a lower peripheral planar face and a circumferential side wall connecting the front and rear planar faces, and wherein the circumferential side wall has a series of protuberances extending outwardly therefrom which define at least two circumferentially spaced wrench receiving formations; and   each of said wrench receiving formations comprising a generally arcuate slot portion which communicates with a transverse opening portion of the formation, the slot portions and transverse opening portions of the formations forming a series of radially extending T-shaped beam members when viewed in a plan view.       

     Preferably, each of the slot portions of the receiving formations forms a pair of oppositely arranged, circumferentially spaced nooks formed at opposite ends of each slot. The receiving formations are selectively sized to receive engaging surfaces of a mating wrench tool, the tool being used to apply torque to the union nut by rotating the union nut. A preferred wrench can be provided wherein the same wrench is engageable with the receiving formations for both making-up and breaking-out the nut from a pipe connection. The preferred union nut is thus hand tightenable with a suitable wrench, without requiring power tongs, or the like. 
     The present invention also encompasses the combination of a previously described torque operable union nut together with a special spanner wrench for turning the union nut. The preferred spanner wrench has a wrench body having a generally arcuate outer periphery and an interior bridge region, the bridge region terminating at either of two opposite ends with an engagement tang for engaging selected ones of the wrench receiving formations in the union nut body. 
     The spanner wrench is sized to span at least two of the receiving formations in the union nut body with the engagement tangs of the wrench body being received in selected receiving formations of the union nut body. At least one of the engagement tangs has a foot region which is engaged within one of the pair of oppositely arranged, circumferentially spaced nooks formed at opposite ends of the receiving formation slots. 
     The spanner wrench body has an upper planar surface, a lower planar surface and a thickness therebetween. A polygonally shaped opening communicates the upper and lower planar surfaces, the polygonally shaped opening being selectively sized to receive an operative member of a torque wrench for applying torque to the spanner wrench and, in turn, to the union nut body. The spanner wrench is preferably provided with an outer peripheral surface which is generally curved in nature and which is designed to deflect the blow of a hammer to discourage use of a hammer in attempting to tighten the union nut. 
     The combination torque operable union nut and spanner wrench further includes an electronic torque wrench engageable with the polygonally shaped opening in the spanner wrench body for providing an electronic indication of the relative torque being applied by the torque wrench. The preferred electronic torque wrench includes a data storage module which can be used to store and retrieve a history of the torque applied at each pipe connection being made with the union nut and spanner wrench. In some cases, the data storage module is an electronic storage disk which can be removed from the electronic torque wrench and read by a remotely located computer. In other cases, the electronic torque wrench can store and transmit data wirelessly to a remote location for establishing a history of the torque applied at each pipe connection being made with the union nut and spanner wrench. 
     An improved method is also shown for tightening a torque operable union nut. In the method of the invention, the previously described union nut is threadedly engaged with one of a respective pair of pipe components to be joined in a pipeline, whereby rotating the union nut tightens the pipeline connection. The previously described spanner wrench is then engaged with the selected receiving formations in the union nut body. A suitable torque wrench is then engaged with the polygonally shaped opening in the spanner wrench body and torque is applied to the spanner wrench and, in turn, to the union nut body to turn the union nut body and tighten the union nut. Preferably, the same spanner wrench is used to engage the union nut for both tightening and untightening the union nut. 
     As previously described, the torque wrench is preferably an electronic torque wrench which is engageable with the polygonally shaped opening in the spanner wrench body for providing an electronic indication of the relative torque being applied by the torque wrench and engaging the electronic torque wrench and recording at least one torque measurement made while tightening the union nut. The electronic torque wrench includes a data storage module which can be used to store and retrieve a history of the torque applied at each pipe connection being made with the union nut and spanner wrench. 
     These and further features and advantages of the present invention will become apparent from the following detailed description, wherein reference is made to the figures in the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-sectional view of a conventional, prior art hammer union employing a spherical metal-to-metal pressure seal. 
         FIG. 1A  is a perspective view of the wing nut portion of the prior art hammer union of  FIG. 1 . 
         FIG. 2  is a view similar to  FIG. 1 , but showing the torque style union of the invention. 
         FIG. 3  is a top plan view of one embodiment of the torque style union of the invention shown being engaged by the make-up break-out wrench of the invention. 
         FIG. 3A  is another top plan view, similar to  FIG. 3 , but showing a smaller spanner wrench engaging the wing nut. 
         FIG. 4  is a front perspective view of one embodiment of the torque style union of the invention showing the make-up break-out wrench engaging two of the outer slots on the wing nut. 
         FIG. 5  is an exploded view of an electronic style torque wrench of the type which is used to engage and turn the spanner wrench of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     While the invention will be described primarily with reference to the union nut and a tool (wrench) for turning the nut, it will be understood that the hammerless connection of the present invention encompasses not only the union nut and wrench system but suitable male and female subs, e.g. such as described with respect to the prior art assembly shown in  FIG. 1 . Further it will be understood that in addition to the metal-to-metal sealing shown in the prior art embodiment of  FIG. 1 , other sealing systems can be employed including elastomeric seals, composite seals, etc. 
     With reference to  FIG. 1 , there is shown a cross sectional view of a typical “hammer union” commonly used for joining conduits together, for example, conduit used to convey drilling mud, fracturing fluids and the like, commonly found in oil and gas operations.  FIG. 1A  shows the same hammer union in perspective. Hammer unions are typically commercially available in, for example, one inch to twelve inch sizes, capable of handling pressures on the order of 1000 psi to as much as 20,000 psi, or more. As shown in  FIG. 1 , hammer unions typically include three major parts: a shouldered male sub; a threaded union nut; and a threaded female sub. The hammer union is typically made-up or broken out by applying a sledgehammer to radial lugs on the threaded union nut. For example, with reference to  FIGS. 1 and 1A , the threaded union nut  11  has hammer lugs  13  which project radially outwardly from nut  11  and which are struck with a sledgehammer to turn and tighten the nut. Union nut  11  also has internal, female threads  15 . As seen, union nut  11  has an annular flange  17  which bears on annular shoulder  19  on a distal end of the shouldered male sub  21 . A sealing surface  23 , in this case a metal-to-metal seal is formed on the end of sub  21 . Threaded female sub  25  has external threads  27  which mate with threads  15  and a sealing surface  29  which forms the other half of the metal-to-metal seal with surface  23 . It will be understood that other types of pressure seals may be utilized, as well, such as those having elastomeric, or composite seals, especially for (relatively) low working pressure unions. 
     Turning then to  FIG. 2 , a torque style “hammerless” union of the present invention is shown in cross-section, designated generally as  10 . The union of the invention includes a male sub shown generally as  12  comprised of a tubular portion  14  on the end of which is formed an annular, radially outwardly projecting head portion  16 . Head portion  16  forms an annular region  18 , e.g., a convex surface formed by a spherical segment but which in any event is radiused. Head portion  16  joins the tubular portion  14  to form an annular shoulder  20 . 
     The union connection of the invention also includes a female sub shown generally as  22  which can comprise a tubular portion  24  and an upset portion  26 , the upset portion  26  having external threads  28 . Upset portion  26  is recessed to form a concave annular seating surface  30  which is complementary in shape to spherical surface  18  such that when surfaces  30  and  18  are in engagement, a metal-to-metal seal can be formed. 
     Connecting the subs  12  and  22  together is a torque style (hammerless) union nut shown generally as  40  in  FIG. 2  and described more fully below. As can be seen, union nut  40  has internal threads  42  which threadedly engage external threads  28  on sub  22  when the connection is made-up. Union nut  40  also has an annular, radially inwardly extending lip portion  44 . Union nut  40  has an upper peripheral planar face  41 , a lower peripheral planar face  43 , and a circumferential outer side wall  54 . Union nut  40  also has a through bore that is provided with internal female threads  42  in surrounding relationship to the through bore. As shown in  FIG. 2 , in the fully made-up position, i.e., when union nut  40  is threaded onto threaded upset portion  26 , lip portion  44  of union nut  40  is forced into engagement with shoulder  20  of male sub  12  forcing surfaces  30  and  18  into metal-to-metal sealing engagement with each other. 
     As perhaps can be best appreciated from  FIG. 3 , the peripheral outer side wall  54  of the union nut  40  has a series of T-shaped beam members or protuberances (such as protuberances  53 ,  55 ,  56 ) extending radially outwardly therefrom which define at least two circumferentially spaced, inwardly extending wrench receiving formations. One such wrench receiving formation is indicated at  49  in  FIG. 3 . Each of the wrench receiving formations further comprises a series of generally circumferentially extending, arcuate slots  52  which communicates with a transverse opening portion  50  (see  FIG. 3 ). Accordingly, there are funned first and second nooks or recesses  58  and  60  located at the terminal ends of each slot. 
     It can thus be seen from  FIG. 3  that each of the pairs of oppositely arranged, circumferentially spaced nooks  58  and  60 , the outer peripheral surface  54  of union nut  40 , and transverse openings  50  comprise the wrench receiving formations for receiving mating engagement portions of a It cooperating spanner wrench, to be further described. 
     In order to thread nut  40  onto female sub  22 , a wrench shown generally as “W” in  FIG. 3  is employed. In the embodiment shown in  FIG. 3 , the spanner wrench W has a wrench body having a curved outer periphery  70 . In the embodiment shown in  FIG. 3 , the outer periphery is generally arcuate shaped. The wrench body also has an interior bridge region  72 . The bridge region  72  terminates at either of two opposite ends with an engagement tang, i.e., tangs  74 ,  76 , for engaging selected ones of the wrench receiving formations in the union nut body. The spanner wrench W is sized to span at least two of the receiving formations in the union nut body with the engagement tangs  74 ,  76 , of the wrench body being received in selected receiving formations of the union but body, at least one of the engagement tangs  74 ,  76  being engaged within one of the pair of oppositely arranged, circumferentially spaced nooks (such as nooks  58 ,  60  in  FIG. 3 ) formed at opposite ends of the receiving formation slots. In the embodiment shown in  FIG. 3 , the spanner wrench W actually spans three of the receiving formations. 
     The spanner wrench body has an upper planar surface  78 , a lower planar surface  79  and a thickness “t” therebetween (see  FIG. 4 ). A polygonally shaped opening  90  communicates the upper and lower planar surfaces  78 ,  79 . The polygonally shaped opening is selectively sized to receive an operative end of a torque wrench for applying torque to the spanner wrench and, in turn, to the union nut body. 
     With reference again to  FIG. 3 , the tang  74  of the wrench forms an U-shaped head portion the most distal portion of which forms a laterally extending foot  58 . The distal end of the opposite tang  76  is truncated, since this is the low pressure side of the connection in the position shown. Thus, as wrench W engages union nut  40  as shown in  FIG. 3 , U-shaped end portion  74  will engage the respective receiving formation designated, while the opposite tang  76  will engage one of the other circumferentially spaced receiving formations. Note again that, with respect to FIG.  4 , the wrench will span at least two of the receiving openings, but as shown in  FIG. 3 , may span three or more openings. The relatively smaller style spanner wrench shown in  FIG. 3A  is designated as “W 1 .” 
     It will be appreciated that in the position shown in  FIG. 3 , wrench W will be moved in the direction of arrow A. Thus, end portion  74  of wrench W is being forced against one end of beam  81  associated with one of the receiving formations. As well, end portion  76  is forced generally radially inwardly such that its distal end contacts the inner peripheral sidewall  54  of the union nut. Thus there will be substantial force vectors tending to rotate nut  40  in the direction of arrow A. Assuming this direction of turn, i.e., that of arrow A shown in  FIG. 3  would result in tightening of nut  40  and accordingly make-up of the union, it will be recognized that if it were desired to break-out the union, i.e., loosen nut  40 , wrench W could be flipped over and inverted oppositely to the position shown in  FIG. 3  (see  FIG. 4 ). This is an important feature, since the same wrench W is engageable with the existing receiving formations for both making-up and breaking-out the nut from a pipe connection. It is also significant to note that the union nut is hand tightenable with the wrench W, and does not typically require a power tong, or the like. 
     Several other features of the union nut/wrench combination of the present invention are important. For one, wrench W can only engage nut  40  by movement of the bridge region  72  and tangs  74 ,  76  into the receiving formations by insertion from an axial direction with respect to the pipe. In other words, engagement by wrench W of nut  40  cannot be accomplished by relative movement of wrench W and nut  40  in a straight-in radial direction, as viewed in  FIG. 3 , Further, as will be appreciated from  FIG. 3 , once wrench W is fully engaged with nut  40 , wrench W cannot be disengaged from nut  40  by straight radial outward movement of wrench W relative to nut  40 . This ensures that when nut  40  is being tightened or loosened by wrench W, wrench W cannot disengage from nut  40  by radial outward movement. It will be appreciated that the shapes of the receiving formations of nut  40  and the shape of head portion of bridge  72  of wrench W can vary. Thus, the shapes shown in the figures are exemplifying several embodiments but the invention is not so limited. Note that the outer peripheral surface (designated as  83  in  FIG. 3 ) is arcuate shaped, or somewhat rounded. This ensures that there is no convenient point for a hammer to be applied to the wrench by an uninformed user. 
     Another important feature of the nut/wrench combination of the present invention, is that when the nut  40  is being moved, whether it be to tighten or loosen nut  40 , there are significant circumferential force vectors being applied by wrench W to nut  40 . 
     With regard to the type of torque wrench used to engage the polygonally shaped opening  90  of the wrench to apply torque, any of a variety of types of commercially available wrenches can be employed. For example, beam and dial systems can be employed. However, easier to use mechanical systems such as click or toggle torque wrench measuring devices are more preferred. In addition to purely mechanical torque measuring systems, electronic torque determinations based on strain gauges, and the like, can also be employed, Many of these systems can include electronic read-out either via a tethered connection to a portable controller or wirelessly to a remote unit. 
     Thus, in a further embodiment, the wrench W of the present invention can be provided with an electronic torque measuring device, shown in simplified fashion as  92  in  FIG. 5 . A number of such devices are commercially available, For example, DMC Corporation of Orlando, Fla., sells the “Angle USB Electronic Digital Torque Wrench” at the present time. It has a drive member  96  for engaging the opening in the spanner wrench, and an onboard memory, illustrated schematically as  94  in  FIG. 5 , which can upload and download information from a personal computer by means of a built-in USB port. This particular device is merely given by way of illustration, as a number of equivalent devices are commercially available at the present time. 
     With an electronic torque measuring device of this type, an on-board data module can be used to store and retrieve a history of the torque applied at each pipe connection being made with the union nut and spanner wrench. In some instances it is envisioned that the data storage module will incorporate an electronic storage disk (Scandisk™ or the like) which can be removed from the electronic torque wrench and read by a remotely located computer. In another embodiment, the electronic torque wrench can store and transmit data wirelessly to a remote location for establishing a history of the torque applied at each pipe connection being made with the union nut and spanner wrench. 
     Although specific embodiments of the invention have been described herein in some detail, this has been done solely for the purposes of explaining the various aspects of the invention, and is not intended to limit the scope of the invention as defined in the claims which follow. Those skilled in the art will understand that the embodiment shown and described is exemplary, and various other substitutions, alterations and modifications, including but not limited to those design alternatives specifically discussed herein, may be made in the practice of the invention without departing from its scope. 
     Thus, while the invention has been shown in several of its forms, it is not thus limited but is susceptible to various changes and modifications without departing from the spirit thereof.