Abstract:
A plunger clamp is disclosed that includes a body comprising a first end, a second end, and a clamp connector disposed between the first and second ends, wherein the clamp connector comprises a threaded portion that interfaces with one or both of the first and second ends facilitating relative rotation with, and separation from, the first and second ends and the clamp connector.

Description:
BACKGROUND OF THE INVENTION 
     Field 
       [0001]    Embodiments of the disclosure generally relate to a plunger clamp utilized in fluid ends in pressurized fluid delivery systems that transfer high volumes of fluids at extreme pressures. 
       Description of the Related Art 
       [0002]    Pressurized fluid delivery systems which include fluid cylinder blocks for transferring fluids at high pressures are used in multiple industries. One example where such systems are used includes the oil and gas industry where high pressure fluid reciprocating pumps, such as multiplex plunger pumps, are commonly used. These types of pumps have a fluid end that includes valves, plungers, liners, among other components, that is driven by a power end that converts the rotation of a drive shaft to the reciprocating motion of the plunger(s) in the fluid end. The pumps facilitate pumping at rates of up to 100 bbl/minute, and are capable of creating variable pressures, e.g., between negative pressures during suction to a discharge pressure of about 1,000 pounds per square inch (psi), or more. A plunger clamp is used to connect a pony rod of the drive shaft to the plunger. 
         [0003]    Conventional plunger clamps are typically compact, one piece structures having a plate on both ends that facilitates coupling of the clamp to the pony rod and the plunger. Each of the plates have fastener holes disposed in shallow blind cavities between the plates. The fastener holes have a bolt pattern that matches a respective bolt pattern of the pony rod and the plunger. Fasteners are inserted into shallow cavities and into the fastener holes during assembly. The fasteners should then be tightened to a specific torque value. However, the close quarters of the shallow cavities make it difficult to insert tools used to tighten and/or verify the torque value. Additionally, debris, such as sand, often packs tightly into the cavities making it even more difficult to insert and/or properly tighten the fasteners. Oftentimes a user may simply tighten the fasteners by hand, or even forego verifying the torque value due to the difficulty of coupling a torque wrench to the fasteners. This presents a major safety hazard as the improperly tightened fasteners may come loose or break during operation which results in injury to personnel and/or damage to the equipment. 
         [0004]    Therefore, there exists a need for an improved plunger clamp. 
       SUMMARY 
       [0005]    In one embodiment, a plunger clamp is described that includes a body comprising a first end, a second end, and a clamp connector disposed between the first and second ends, wherein the clamp connector comprises a threaded portion that interfaces with one or both of the first and second ends facilitating relative rotation with, and separation from, the first and second ends and the clamp connector. 
         [0006]    In another embodiment, a plunger clamp is disclosed that includes a body comprising a first end, a second end, and a clamp connector disposed between the first and second ends, wherein the clamp connector comprises a threaded portion that interfaces with one or both of the first and second ends, the clamp connector includes a plurality of tool interfaces formed on a perimeter thereof that extend in a direction orthogonal to a longitudinal axis of the body, and the first and second ends include recessed portions corresponding to positions of fastener holes formed therethrough. 
         [0007]    In another embodiment, a fluid end is described that includes a body having a plurality of bores formed therein that intersect at a junction, a plunger disposed in one of the bores, and a plunger clamp coupled to the plunger. The plunger clamp comprises a body comprising a first end, a second end, and a clamp connector disposed between the first and second ends, wherein the clamp connector comprises a threaded portion that interfaces with one or both of the first and second ends, and one or both of the first end and the second end, and the clamp connector, includes a plurality tool interfaces formed on a perimeter thereof that extend radially inward in a direction orthogonal to a longitudinal axis of the body. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    Having generally described the various embodiments of the disclosure, reference will now be made to the accompanying drawings. 
           [0009]      FIG. 1  is an isometric view of a fluid end. 
           [0010]      FIG. 2  is a cross-sectional view of the fluid end along lines  2 - 2  of  FIG. 1 . 
           [0011]      FIG. 3A  is an isometric view of one embodiment of a plunger clamp. 
           [0012]      FIG. 3B  is an exploded isometric view of the plunger clamp of  FIG. 3A . 
           [0013]      FIG. 3C  is a section view of the plunger clamp along lines  3 C- 3 C of  FIG. 3A . 
           [0014]      FIG. 4  is a schematic side cross-sectional view of another embodiment of a clamp connector. 
           [0015]      FIG. 5A  is an isometric view of another embodiment of a plunger clamp. 
           [0016]      FIG. 5B  is an exploded isometric view of the plunger clamp of  FIG. 5A . 
           [0017]      FIG. 5C  is a section view of the plunger clamp along lines  5 C- 5 C of  FIG. 5A . 
           [0018]      FIG. 6A  is an isometric view of another embodiment of a plunger clamp. 
           [0019]      FIG. 6B  is an exploded isometric view of the plunger clamp of  FIG. 6A . 
           [0020]      FIG. 6C  is a section view of the plunger clamp along lines  6 C- 6 C of  FIG. 6A . 
       
    
    
       [0021]    To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one embodiment may be beneficially utilized on other embodiments without specific recitation. 
       DETAILED DESCRIPTION 
       [0022]      FIG. 1  is an isometric view of a fluid end  100  having a fluid cylinder body  105 .  FIG. 2  is a cross-sectional view of the fluid end  100  along lines  2 - 2  of  FIG. 1 . The fluid end  100  includes a plurality of bores  110 A- 110 D ( 110 A and  110 D are shown  FIG. 2 ) formed in the body  105 . The fluid end  100  is adapted to couple to a power end  112  via a pony rod  114 . While only one pony rod is shown, the power end  112  may have a pony rod that couples to each of the bores  110 A of the fluid end  100 . 
         [0023]    The fluid end  100  includes cover nuts  115  disposed in at least a portion of the bores  110 B and  110 C. A gauge connector  120  may be coupled to one of the bores  110 B by a gauge connector nut  125 . A discharge flange  130  may be coupled to opposing ends of the body  105  for connecting hoses with a discharge manifold (not shown). A plunger clamp  135  may be disposed between the fluid end  100  and the pony rod  114 . 
         [0024]    Referring to  FIG. 2 , the internal components of the fluid end  100  will be described. A plunger  200  is shown disposed in the bore  110 A and a valve assembly  205  having a spring  210  is shown disposed in the bore  110 B. A suction cover seal gland  215  is shown disposed in the bore  110 C and a valve stop  218  is shown in bore  110 D. A valve body  222  as well as a valve seat  224  may also be disposed in the bores  110 B and  110 D. The body  105  may also include a discharge manifold  220  formed therein that is in selective communication with at least the bore  110 B. The bores  110 A- 110 D intersect within the body  105  at a junction  225 . 
         [0025]      FIGS. 3A-3C  are various views of one embodiment of a plunger clamp  300  that may be used as the plunger clamp  135  of  FIGS. 1 and 2 .  FIG. 3A  is an isometric view of the plunger clamp  300 .  FIG. 3B  is an exploded isometric view of the plunger clamp  300  of  FIG. 3A .  FIG. 3C  is a section view of the plunger clamp  300  along lines  3 C- 3 C of  FIG. 3A . 
         [0026]    The plunger clamp  300  includes a multi-piece body  302  including a first end  305  that is adapted to couple with a plunger, such as the plunger  200  shown in  FIG. 2 . The plunger clamp  300  includes a second end  310  that is adapted to couple to a pony rod, such as the pony rod  114  if  FIG. 1 . A collar or clamp connector  315  is disposed between the first end  305  and the second end  310 . 
         [0027]    Holes  320  are formed in both of the first end  305  and the second end  310  along a longitudinal axis  322  of the body  302  for connecting to the plunger and the pony rod using fasteners (not shown), such as bolts or screws. Blind holes  325 , which may comprise a tool interface, are formed in at least a portion of the body  302  along a radial direction (orthogonal to the direction of the longitudinal axis  322  of the body  302 ) for coupling the first end  305  to the second end  310 . For example, blind holes  325  may be formed in the clamp connector  315  and at least one of the first end  305  (as shown) or the second end  310 , providing an interface for a tool (not shown), such as a spanner wrench, in order to rotate the clamp connector  315  relative to the first end  305  and/or the second end  310 . Other tool interfaces are contemplated, such as two or more flats formed on a perimeter of the first end  305  or the second end  310 , and on a perimeter of the clamp connector  315  for using a conventional open end wrench. In another example, grooves may be formed on a perimeter of the first end  305  or the second end  310 , and on a perimeter of the clamp connector  315  in order to increase friction when using a tool, such as a chain wrench, in order to rotate the clamp connector  315  relative to the first end  305  and/or the second end  310 . 
         [0028]    As shown in  FIGS. 3B and 3C , the first end  305  and the clamp connector  315  includes a threaded connection  330 . The threaded connection  330  allows the first end  305  to be fixed to the second end  310 , or allows the first end  305  to be separated from the second end  310 . In  FIG. 3C , the clamp connector  315  includes female threads  335  and the first end  305  includes male threads  340 . The male threads  340  may be inserted into an opening  345  formed in a center of the clamp connector  315 . The male threads  340  may be broken by recessed portions  350 . Additionally, the second end  310  includes recessed portions  355  formed in a side thereof. The recessed portions  350 ,  355  correspond to positions of the openings  320  and may be utilized to provide space for a fastener (not shown), such as a fastener head or a nut. As shown in  FIGS. 3B and 3C , a circular retainer member  360 , such as a snap ring may be utilized to couple the second end  310  to the clamp connector  315 . An annular groove  365  formed in the second end  310  may be used to capture the circular retainer member  360 . Alternatively, the circular retainer member  360  and groove  365  may be replaced by a threaded ring (not shown) that may be attached to threads (not shown) formed on an end  370  of a hub  375  of the second end  310 . 
         [0029]    An example for coupling the plunger clamp  300  to the plunger, such as the plunger  200  and the pony rod, such as the pony rod  114 , is as follows. The first end  305  may be disconnected from the clamp connector  315  for this exemplary coupling procedure. Likewise, the clamp connector  315  may be disconnected from the second end  310  for this exemplary coupling procedure. 
         [0030]    Both of the first end  305  and the second end  310  may be coupled to the plunger and the pony rod, respectively, using fasteners. The fasteners can be tightened and torqued according to specifications as the first end  305  and the second end  310  are disconnected from each other as well as the threaded connection  330 . Then, the clamp connector  315  may be coupled to the second end  310  by positioning the opening  345  about the hub  375 , and attaching the circular retainer member  360  thereon to secure the clamp connector  315  to the second end  310 . The clamp connector  315  may then be rotated onto the threads  335  of the first end  305  to bring the first end  305  closer to the second end  310 . The first end  305  and the clamp connector  315  may be tightened using the blind holes  325 . A torque value may be specified for the threaded connection  330  to ensure the threaded connection  330  does not loosen over time. 
         [0031]      FIG. 4  is a schematic side cross-sectional view of another embodiment of a clamp connector  400  that may be utilized to replace the clamp connector  315  of  FIGS. 3A-3C . The clamp connector  400  includes a split-ring collar having a first portion  405  and a second portion  410  adapted to be coupled to each other using fasteners, such as a bolt  415  and a nut  420 . The fasteners may be disposed in through-holes  425  formed in both of the first portion  405  and the second portion  410 . Torque values may be specified for the bolts  415  and the nuts  420 . The first portion  405  and the second portion  410  includes the blind holes  325  formed on a perimeter thereof as well as female threads  335  formed on an interior surface thereof. When the first portion  405  and the second portion  410  are coupled together, a connector body  430  is provided, which may be rotated onto the threads  335  of the first end  305  to bring the first end  305  closer to the second end  310 . The blind holes  325  may be utilized to tighten the connector body  430  according to the exemplary installation procedure described above. 
         [0032]      FIGS. 5A-5C  are various views of another embodiment of a plunger clamp  500  that may be used as the plunger clamp  135  of  FIGS. 1 and 2 .  FIG. 5A  is an isometric view of the plunger clamp  500 .  FIG. 5B  is an exploded isometric view of the plunger clamp  500  of  FIG. 5A .  FIG. 5C  is a section view of the plunger clamp  500  along lines  5 C- 5 C of  FIG. 5A . 
         [0033]    The plunger clamp  500  includes a multi-piece body  502  that is similar to the plunger clamp  300  shown and described in  FIGS. 3A-3C  with the following exceptions. The plunger clamp  500  includes a segmented retainer  505  (shown in  FIGS. 3B and 3C ) that in addition to the circular retainer member  360  of  FIGS. 3B-3C . 
         [0034]    According to this embodiment, the segmented retainer  505  includes a plurality of segments  515  that are coupled to each other using the circular retainer member  360 . The segmented retainer  505  may be placed about the hub  375  of the second end  310  in segments  515 , and the segments  515  may be retained be installing the circular retainer member  360  in a groove  520  formed in each of the segments  515 . Each of the segments  515  of the segmented retainer  505  may include a radial wall  525  formed on each of the segments  515  and the radial walls  525  may be retained on the hub  375  by a circular band  530  formed on the hub  375 . The installation of the plunger clamp  500  may be similar to the installation of the plunger clamp  300  described in  FIGS. 3A-3C . 
         [0035]      FIGS. 6A-6C  are various views of another embodiment of a plunger clamp  600  that may be used as the plunger clamp  135  of  FIGS. 1 and 2 .  FIG. 6A  is an isometric view of the plunger clamp  600 .  FIG. 6B  is an exploded isometric view of the plunger clamp  600  of  FIG. 6A .  FIG. 6C  is a section view of the plunger clamp  600  along lines  6 C- 6 C of  FIG. 6A . 
         [0036]    The plunger clamp  600  includes a multi-piece body  602  that is similar to the plunger clamp  300  shown and described in  FIGS. 3A-3C  with the following exceptions. A clamp connector  605  of the plunger clamp  600  includes threaded members  610  extending from a central flange  615  thereof (only one threaded member  610  is shown in  FIG. 6A . 
         [0037]    As shown in  FIGS. 6B and 6C , the threaded members  610  include threads  620  and threads  625  that are opposing the threads  620 . For example, the threads  620  may be right-handed threads and the threads  625  may be left-handed threads. The threads  620  are adapted to interface with mating threads  630  provided in an opening  632  of the first end  305 . Likewise, the threads  625  are adapted to interface with mating threads  635  provided in an opening  632  of the second end  310 . 
         [0038]    To couple the plunger clamp  600  to the plunger, such as the plunger  200  and the pony rod, such as the pony rod  114 , the first end  305  may be disconnected from the clamp connector  605 . Likewise, the clamp connector  605  may be disconnected from the second end  310 . Both of the first end  305  and the second end  310  may be coupled to the plunger and the pony rod, respectively, using fasteners. The fasteners can be tightened and torqued according to specifications as the first end  305  and the second end  310  are disconnected from each other as well as the clamp connector  605 . 
         [0039]    The threaded connection  330  provided by the threads  620  and  630 , and the threads  625  and  635  may provide a configuration such that the clamp connector  605  functions as a turnbuckle. After the connection of the first end  305  and the second end  310  to the plunger and the pony rod, respectively, the clamp connector  605  may be coupled to the first end  305  by rotating the clamp connector  605  relative to the first end  305 . Simultaneously, the clamp connector  605  may be coupled to the second end  310  by rotating the clamp connector  605  relative to the second end  310 . The blind holes  325  of the clamp connector  605  and/or the first end  305  may be used to tighten the clamp connector  605  to the first end  305  and the second end  310 . A torque value may be specified for the threaded connection  330  to ensure the threaded connection  330  does not loosen over time. 
         [0040]    Embodiments of the plunger clamps  300 ,  500  and  600  as described herein easily secures a pony rod to a plunger of a fluid end with a connection that is enables proper torqueing of fasteners, which enables safer operation. The plunger clamps  300 ,  500  and  600  may be disassembled such that each side (the first end and the second end) can be installed without being connected to each other, which facilitates tightening of fasteners to the required torque values. The plunger clamps  300 ,  500  and  600  as described herein is usable on existing equipment without any additional machining or retrofitting to existing fluid ends, plungers and/or power ends. The plunger clamps  300 ,  500  and  600  may be installed without removal of the plunger from the fluid end which saves considerable time. The plunger clamps  300 ,  500  and  600  may be installed using standard tools, such as spanner wrenches or packing nut bars. The plunger clamps  300 ,  500  and  600  are significantly cheaper to manufacture than conventional clamps and the side that couples to the plunger (e.g., the first side  305 ) fits all plunger sizes. This reduces the quantity and cost of expendable parts the operator must keep in inventory as well as reducing operational and maintenance downtime. 
         [0041]    While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.