Patent Publication Number: US-2021180730-A1

Title: Hammerless pipe union

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 15/854,591, filed Dec. 26, 2017, which claims the benefit of U.S. Provisional Application No. 62/440,768 filed Dec. 30, 2016, each of which is incorporated by reference herein in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The disclosed technology relates to the field of pipe couplings and more particularly to couplings used for pipes employed in petroleum recovery systems and mining. 
     BACKGROUND 
     Hammer unions are well known couplings used in the oil, gas and mining industries for fastening pipe together. For example, pipe carrying high-pressure fluids such as drilling mud, fracturing fluids and oil and gas produced in drilling activities may be coupled using hammer unions. Hammer unions generally comprise an annular metal body having a thread end and a nut end with one or more lugs or wing nuts extending outwardly from the annular body which can be struck with a hammer to rotate the hammer union in order to tighten or loosen it. 
     U.S. Patent Publication No. US 2012/0048069, incorporated herein by reference in its entirety, describes a hammer union wrench comprising a tool head having a substantially circular or disk shaped tool head body with an opening there through axially and transversally. The axial opening also includes slots which receive tabs associated with the hammer union. Although this is a useful arrangement, it requires the engagement of at least two of the tabs or bosses of the hammer union and fairly specific alignment of the tool head relative to the hammer union. 
     Other tools used with hammer unions are spanner wrenches. An example of one such arrangement is shown in U.S. Patent  2 , 830 , 480 , incorporated herein by reference in its entirety. This wrench has a semicircular tool head with a series of recesses and projections positioned on the tool head. The recesses and projections mate in registration with similarly configured recesses and projections in the tubing union. 
     U.S. Pat. No. 464,084, incorporated herein by reference in its entirety, describes a curved jaw tool head with a tooth positioned within the jaw and guiding ears associated therewith. 
     U.S. Pat. No. 2,691,912 incorporated herein by reference in its entirety, describes an anvil type wrench. The wrench effectively comprises a body suitable for use in pipe union fittings. 
     U.S. Pat. No. 1,528,892, incorporated herein by reference in its entirety, describes a wrench which has an internally-directed U-shaped head. 
     Japan Patent document JP 477315462, incorporated herein by reference in its entirety, describes a pipe fitting with a cam lever for locking pipes together. 
     Japan Patent document JP 0904959A, incorporated herein by reference in its entirety, describes a pipe joint with a handle-operated nut coupler. 
     Japan Patent document JP 2010169166A, incorporated herein by reference in its entirety, describes a bite type pipe connection structure with a cam surface to which a distal end of a ferrule is pressed is provided on a joint body. 
     U.S. Pat. No. 2,417,025, incorporated herein by reference in its entirety, describes a hammer lock union which is locked in place using a lateral pin. 
     U.S. Pat. No. 4,697,830, incorporated herein by reference in its entirety, describes a guide system for protecting threads and seals when joining lengths of production tubing. The system includes removable handles secured by large bolts. 
     U.S. Pat. Nos. 8,118,528, and 8,657,547, each of which is incorporated herein by reference in its entirety, each describe variations of a field replaceable hammer union wing nut with removable hammer pads. 
     U.S. Patent Publication No. 2015/0226355, incorporated herein by reference in its entirety, describes a hammer union connector which includes male and female pipe connectors, a threaded nut and load segments for insertion between the nut and the male sub. 
     There continues to be a need for improving pipe union systems for use in the oil, gas and mining industries for fastening pipes together. 
     SUMMARY 
     In one aspect, there is provided a device for forming a union of pipe ends, the device comprising: a) two pipe connectors, each configured for attachment to an end of a length of pipe at one end and each configured for joining to the other of the two connectors at the other end; b) a nut having a bore with internal threads configured to mate with outer threads on the outer surface of one or both of the two pipe connectors, the outer lateral surface of the nut having a plurality of handle connection structures; and c) a handle for increasing the amount of manually-generated torque on the nut during tightening or loosening of the nut with respect to the outer threads, the handle having a nut attachment end configured to engage the handle connection structures, the handle further provided with a mechanism for reversibly locking the handle to any one of the plurality of handle connection structures of the nut. 
     In some embodiments, the two pipe connectors are a female connector and a male connector. 
     In some embodiments, the outer threads are present only on the female connector and the male connector includes an outer abutment which cooperates with a ridge in the bore of the nut to stop the threading of the inner threads onto the outer threads. 
     In some embodiments, the handle connection structures are defined as sockets formed in the outer lateral surface of the nut, the sockets configured to receive the nut attachment end of the handle. 
     In some embodiments, the handle connection structures are defined as protrusions formed in or attached to the outer lateral surface of the nut, the protrusions configured to be received by sockets formed in the nut attachment end of the handle. 
     In some embodiments, the mechanism for connecting and reversibly locking the handle to each one of the plurality of handle connection structures of the nut is provided by a retaining pin configured to pass through aligned openings in the nut and in the nut attachment end of the handle. 
     In some embodiments, the device further comprises a hammer pad having a nut attachment end configured a mechanism for connecting and reversibly locking the hammer pad to each one of the plurality of handle connection structures of the nut, the hammer pad provided to present a flat laterally extending surface for striking with a hammer to increase the amount of manually-generated torque on the nut during tightening or loosening of the nut with respect to the outer threads. 
     In some embodiments, the mechanism for connecting and reversibly locking the hammer pad to each one of the plurality of handle connection structures of the nut is provided by a retaining pin configured to pass through aligned openings in the nut and in the nut attachment end of the hammer pad. 
     In some embodiments, the plurality of handle connection structures is six equi- spaced handle connection structures. 
     Another aspect of the disclosed technology is a kit for forming a union of two pipe ends. The kit includes the device as described herein in combination with instructions for forming a union of two pipes using the device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various objects, features and advantages of the disclosed technology will be apparent from the following description of particular embodiments, as illustrated in the accompanying drawings. The drawings are not necessarily to scale. Emphasis is instead placed upon illustrating the principles of various embodiments of the technology. 
         FIG. 1  is a perspective view of the separated parts of one embodiment of the hammerless union which includes a female connector  12 , a male connector  14  (respectively welded to pipes P- 1  and P- 2 ), a nut  16 , a handle  18  and a retaining pin  19  for holding the handle  18  in a socket  22   b  of the nut  16  as indicated by the partial exploded view. 
         FIG. 2  is a perspective view of the same embodiment of  FIG. 1  shown in a reversed orientation. 
         FIG. 3  is a perspective view of the same embodiment of  FIGS. 1 and 2  in generally the same orientation of  FIG. 1  showing a hammer pad  24  in place of the handle  18 . 
         FIG. 4  is a perspective view of the same embodiment of  FIGS. 1-3  in generally the same orientation as  FIG. 1  with the hammerless union fastened in place to fasten the two pipes P- 1  and P- 2 . 
         FIG. 5  is an arbitrary longitudinal cross section of  FIG. 4  taken through the center of the union between any two of the six sockets  22   a - f  of the nut  16 . 
         FIG. 6  is a perspective view of an embodiment of the hammerless pipe union wherein the nut  16  includes protrusions  36  configured to fit into a socket  38  formed on handle  18 . 
     
    
    
     DETAILED DESCRIPTION 
     Rationale 
     Over time, repetitively striking the wing nuts on a hammer union damages the wing nuts, causing them to wear down and become misshapen. This causes the wing nuts more difficult to strike accurately with a hammer. If the wing nuts become too damaged, the entire hammer union must be replaced. Replacing a hammer union is generally costly and time consuming because the pipe must be cut apart and re-welded. This is generally becoming more of a problem as more expensive pipes are increasingly being used in drilling mud systems in oil and gas wells to accommodate higher pressures. The inventors are engaged in efforts to improve union devices for joining pipes and have developed the technology which is described hereinbelow in context of an example embodiment. 
     Various aspects of the disclosed technology will now be described with reference to the figures. For the purposes of illustration, components depicted in the figures are not necessarily drawn to scale. Instead, emphasis is placed on highlighting the various contributions of the components to the functionality of various aspects of the disclosed technology. A number of possible alternative features are introduced during the course of this description. It is to be understood that, according to the knowledge and judgment of persons skilled in the art, such alternative features may be substituted in various combinations to arrive at different embodiments of the disclosed technology. 
       FIGS. 1 to 5  illustrate one embodiment of a hammerless union device for joining ends of two pipes P- 1  and P- 2 . In this embodiment, the end of pipe P- 1  is provided with a female connector  12  and pipe P- 2  is provided with a male connector  14  which is configured to mate with the female connector  12  to make a pipe connection. The connection is tightened using an internally threaded union nut  16  which is threaded onto external threads  20  on the outer sidewall of the female connector  12 . In some embodiments, the connectors  12  and  14  are fixed to the pipe ends by welding. In other embodiments, the connectors  12  and  14  have rearward threads which are configured for threading attachment to threaded pipes. 
     Once the female  12  and male  14  connectors are mated, a union nut  16  is placed over the two mated connectors to fix them in place. For greater clarity and with respect to the example embodiment, during installation of the hammerless union device on a pair of pipes P- 1  and P- 2 , the nut  16  is installed on pipe P- 2  prior to connection (e.g. by welding) of the male connector  14  to the pipe P- 2  because the interior sidewall of the bore of the nut  16  is provided with a circumferential ridge  32  which provides a reduced diameter bore acting as a stop when it encounters a circumferential abutment  34  formed in the outer sidewall of the male connector  14 . This arrangement prevents the nut  16  from moving past the male connector  14 . In this particular embodiment, the nut  16  has a central bore which has a majority portion with a threaded interior sidewall  26  (best illustrated in  FIGS. 1, 3 and 5 ). The threaded interior sidewall  26  is configured to thread onto outer threaded surface  20  of the female connector  12 . 
       FIG. 2  is a perspective view of the same embodiment of  FIG. 1  which is reversed relative to the perspective view of  FIG. 1 . It is seen in this perspective view (and in the cross section shown in  FIG. 5 ) that the interior of the female connector  12  has a seat  30  for an o-ring to prevent leaks from the union device when it is installed to join the pipes P- 1  and P- 2 . 
     The nut  16  is provided with a plurality of handle connection structures, which in this particular example embodiment, are in the form of six equi-spaced square sockets  22   a - f  formed in the outer lateral side of the nut  16 . These sockets  22   a - f  are dimensioned to accept the square end of a handle  18 , the purpose of which is to provide leverage for torquing the nut  16  during tightening or loosening of the nut  16 . It is advantageous to lock the handle  18  in place. In  FIG. 4 , the handle  18  is shown locked to socket  22   b  using a retaining pin  19  which is inserted into transverse holes  23   b  and  23   b ′ formed in the nut  16  (shown in the partially exploded view of  FIG. 1 ). The square end of the handle  18  has an opening  25  for accepting the retaining pin  19 . Thus, to lock the handle  18  in place in socket  22   b,  the pin  19  is inserted into hole  23   b  and pushed to insert it through opening  25  in the handle  18  and then through hole  23   b ′. With the handle  18  locked in place on the nut  16 , a user may confidently apply significant torque to the nut  16  during tightening or loosening of the nut  16 . 
     As noted above, the nut  16  of this embodiment includes six sockets  22   a - f.  Each one of the sockets is provided with a similar handle locking arrangement described above and thus sockets  22   a - f  have adjacent holes  23   a - f  and  23   a ′- f ′ although not all of these are visible in the views of  FIGS. 1-5 . The purpose of providing the six sockets  22   a - f  is to allow a user to engage the handle  18  at a plurality of positions in order to avoid obstacles which may exist in the vicinity of the hammerless union device when it is being assembled or disassembled. 
     In certain situations, the union device may be found to have been tightened excessively or affected by other environmental factors to an extent that sufficient torque cannot be applied to the connected handle  18  to loosen the nut  16 . The present embodiment provides an alternative mechanism for increasing torque on the nut  16  by providing a removable hammer pad  24 .  FIG. 3  illustrates connection of a hammer pad  24  to the nut  16  in an exploded perspective view. The hammer pad  24  is provided with a square end having an opening  27  for engagement of the retaining pin  19  in the same manner as described above for locking the handle  18 . As described above for the handle  18 , the hammer pad  24  may be engaged to the nut  16  at any one of the six sockets  22   a - f  in order to avoid obstacles in the vicinity of the union. In some embodiments, the hammer pad  24  is formed of a durable alloy such as brass or other similar alloy which does not generate sparks upon impact by a hammer. 
     Alternative Embodiments 
     It is to be understood that in alternative embodiments, the female connector  12  and the male connector  14  are replaceable with any other connector or adapter structures, provided that they are configured to join with each other to form at least a temporarily joined or coupled structure which may be rigidly fastened using an overlying structure exemplified by the nut  16  described herein. Although the male-female mating structures described herein as well as other possible male-female mating structures are advantageous for holding pipe ends together prior to fastening using a union structure, other connector structures are known to those with ordinary skill in the art and can be configured for fastening using a hammerless union nut as described hereinbelow. 
     While the example embodiment described above uses nut sockets to receive a handle, the skilled person will recognize that a reversed arrangement is also possible, as shown in  FIG. 6 , wherein the nut  16  is provided with protrusions  36  configured to fit into a socket  38  formed on an alternative handle  18 . This arrangement is also amenable to locking using a retaining pin  19  inserted into a hole  23  similar to the pin described above. This alternative embodiment is also within the scope of the disclosure. 
     While the example embodiment described above includes a threaded surface  20  on the female connector  12 , outer threads  20  may be present on the outer surface of both of the two pipe connectors, as shown in  FIG. 6 . 
     While a retention pin mechanism has been described as a handle/hammer pad locking mechanism, the skilled person will recognize that alternative locking mechanisms are possible, such as a button detent mechanism for example. Such alternative locking mechanisms are considered equivalents of the mechanism shown in the example embodiment and can be arranged by the skilled person without undue experimentation in development of alternative embodiments which are also within the scope of the disclosure. 
     While the example embodiment described above has six equi-spaced handle connection structures in the form of square sockets  22   a - f,  it is to be understood that useful alternative embodiments may include fewer sockets, but it is advantageous to include at least two handle connection structures to allow a user to avoid obstacles in the vicinity of the union. Sockets and cooperating handle and/or hammer pad connection ends with different shapes are also within the scope of the disclosure. 
     Equivalents and Scope 
     The terms “one,” “a,” or “an” as used herein are intended to include “at least one” or “one or more,” unless otherwise indicated. 
     Any patent, publication, internet site, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated material does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material. 
     Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this technology belongs. 
     While this technology has been particularly shown and described with references to embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope encompassed by the appended claims.