Patent Publication Number: US-2023151721-A1

Title: Clamp connection for use with flowlines and/or components of a hydraulic fracturing operation

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority from U.S. Provisional Patent Application Ser. No. 63/279,820, filed on Nov. 16, 2021, and entitled “Clamp Connection for Use with Flowlines and/or Components of a Hydraulic Fracturing Operation”. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to hydraulic fracturing operations. More particularly, the present invention relates to clamp connections used for joining components of such fracturing operations. More particularly, the present invention relates to clamp connections for joining flowlines and other components of a hydraulic fracturing operations. 
     2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98. 
     In some oil field service operations, such as hydraulic fracturing, cementing, acidizing and the like, high-pressure fluids are pumped down the well. In some cases, the fluid pressures may be in excess of 15,000 p.s.i. Typically, an operator brings high-pressure pumping equipment to the well site and installs temporary service flowlines from the high-pressure pumps to the wellhead. Because high volumes of fluid may be needed, a number of pumping units may be connected together at one well site. 
     The temporary flowline components include joints or sections of steel pipe of differing lengths, various junctions, valves, swivels and the like. Generally, each well site differs, and the workers have to arrange the flowlines to extend around and past a variety of well site equipment. Many connections have to be made up, and each connection must be able to withstand the high-pressure forces. The workers need to be able to quickly make and break-out the connections to minimize the time for each job. 
     A hammer union is a common type of connector used for these temporary flowlines. The flowline components have ends that abut each other. A collar fits loosely on one end. The collar has internal threads for engaging threads on the end of the other flowline component. The collar has external lugs, and the workers deliver blows to the lugs to tighten the collars. While these hammer union systems work well, there are various disadvantages. The larger size components can be fairly heavy. The ends being joined have to be elevated above the ground to tighten the hammer union. A worker might sustain an injury while lifting the components and delivering blows with a hammer In very cold climates, the hammer union could shatter or break due to the blows. Sparks can be created by delivering the blows, which could create an explosion if any combustible gas has leaked in the vicinity. The task of connecting the components with a hammer union is also time-consuming. 
     Another type of temporary oilfield service flowline utilizes clamps to clamp the ends of the flowlines together. The workers employ wrenches to secure four bolts that draw the clamp halves together. The clamp engages annular external flanges formed on the ends of the flowline components. A cylindrical seal recess is formed in the bore at the end of each flowline component. The cylindrical recess terminates in a shoulder that is parallel to the end face of the flowline component. A cylindrical metal carrier ring fits within but does not seal to the cylindrical seal recess. Rather, a clearance exist between the recess and the carrier ring to facilitate entry of the carrier ring into the recess. Elastomeric seal rings are mounted to the carrier ring to seal against the cylindrical portions and shoulders of the recesses. This type of service flowline avoids the disadvantages of hammer unions, but is not in wide use. 
     In the clamp-type of temporary flowline mentioned above, the external dimensions of the clamps are fairly large because the external flanges protrude considerably more than the outer diameter of the flowline component. Reducing the size would make setting up flowlines more convenient because of compactness. However, the high-pressure ratings mandate a certain amount of support metal and still must be maintained. 
     Another type of flowline connector uses clamps that are secured to the tubular members. In that type, the seal ring has conical surfaces that form metal-to-metal seals with conical surfaces formed in the passages of the tubular members. While able to sustain high pressures, these connectors are not normally used for oilfield service work because the metal seals would not withstand daily make-up and break-out. The metal-to-metal seals also become very difficult to remove and replace. As such, the various components are utilized in a one-use manner. It would be desirable, in the field, that the components would be able to be separated from each other, reattached, and reused. As such, a need has developed so as to avoid the use of such metal-to-metal seals in such hydraulic fracturing flowlines. 
     In the past, a variety of patents have issued with respect to these clamp connections used in hydraulic fracturing operations. For example, an early patent directed to engaging tubular members together is shown in U.S. Pat. No. 2,766,999, issued on Oct. 16, 1956 to Watts et al. This patent describes a conduit connection with conically-formed inter-engaging seats on seal and connection members. A unitary continuous sealing ring of hard metal is utilized. This unitary continuous sealing ring comprises an inner annular flange portion with oppositely disposed flexible lips and an integral substantially centrally disposed external rib portion. The lips have exterior sealing surfaces which taper outwardly toward the rib portion at an angle not exceeding 35° with respect to the longitudinal axis of the sealing ring. The tapered lips are undercut at the juncture points of the exterior sealing surfaces with the rib portion. 
     U.S. Pat. No. 3,216,746, issued on Nov. 9, 1965 to J. D. Watts, teaches a sealing ring component having first and second annular parts having annular end surfaces presented toward one another in coaxial alignment. There is a conically tapered radially inwardly facing sealing surface on each of the annular parts. The sealing surfaces each extend at an acute angle with respect to the longitudinal axis of the parts and increase in radius toward the annular end surfaces. The sealing surfaces join the annular end surfaces at the radially inner extent of the annular end surface. An annular sealing ring of hard metal or the like provides a seal between the parts when they are drawn toward one another. The sealing ring has a radially inner annular flange portion having a pair of oppositely-disposed annular flexible lips with an integral substantially centrally disposed annular rib portion having a pair of oppositely axially facing end surfaces. 
     U.S. Pat. No. 4,218,080, issued on Aug. 19, 1980 to W. D. Kendrick, discloses a repairable composite seal ring for a conduit connection. The seal assembly has first and second conduit parts. Each of the conduit parts has an axially extending flow passage and an end surface radially intersecting the flow passage. Each of the conduit parts has an internal sealing cavity adjacent the end surface and radially offset from the flow passage. A composite annular seal is interposed between the conduit parts and extends into the two sealing cavities. The composite annular seal includes a central rim portion from which extend two generally axially-disposed lip portions projecting oppositely outwardly into the conduit sealing cavities. Each lip portion has an annular groove therein. 
     U.S. Pat. No. 6,832,789, issued on Dec. 21, 2004 to K. L. Church, shows a threaded pipe connection with a cylindrical metal-to-metal high-pressure containment seal. This connection utilizes a separate ramp or ramp regions that simulate a pin swaging or a box expansion which results in the ability of the cylindrical components of the seal to assemble without interference with only slight interference. 
     U.S. Pat. No. 7,204,525, issued on Apr. 17, 2007 to M. D. Matzner, shows a flowline connection assembly that connects first and second tubular members to each other. Each tubular member has a proximal flange on its end. The conical recess is formed in the bore at the ends of each of the tubular members. A metal ring has a pair of legs extending in opposite axial directions. Each of the legs has a conical outer surface that engages one of the conical recesses. Each ring has an elastomeric seal that seals the recess. A clamp has cam surfaces that engage the flanges and pulls the tubular members axially toward each other. 
     U.S. Pat. No. 7,549,681, issued on Jun. 23, 2009 to M. D. Matzner, describes a flowline connection assembly that connects first and second tubular members to each other. Each tubular member has an external flange on its end. A recess is formed in the bore at the end of each of the tubular members. A seal ring extends into each of the conical recesses. A clamp with a pair of halves includes cam surfaces that engage the flanges and pulls the tubular members axially toward each other. Bolts extend from one clamp half to the other. A retainer ring on each bolt retains the bolts with one of the clamp halves. 
     U.S. Pat. No. 7,823,265, issued on Nov. 2, 2010 to Matzner et al., teaches a flowline torque arm assembly for removing a pair of flowline members relative to each other. This assembly has a pair of flowline collars that are adapted to connect to an end portion of one of the pair of flowline members. The assembly has an arm member with an end portion rotationally mounted to one of the flowline collars and a connecting member pivotally mounted to the other flowline collar. The connecting member is pivotally mounted to the arm member a distance away from the end portion of the arm member that is connected to the flowline collar so that rotational movement of the arm member moves the flowline members relative to each other. 
     U.S. Pat. No. 8,978,695, issued on Mar. 17, 2015 to Witkowski et al., teaches a check valve assembly that has a body with the central cavity intersected by upstream and downstream flow passages. A seat is secured by a threaded engagement in the upstream flow passage. An access bore intersects the cavity and has a support shoulder formed in it. A holder is supported on the support shoulder. A flapper is pivotally secured to the holder and is located in the cavity for movement between an open position and a closed position. A straight edge portion in the access bore engages a straight edge portion of the holder to prevent rotation of the holder. A fastener extends through a hole in the support shoulder into engagement with the seat to prevent rotation of the seat. 
     It is an object of the present invention to provide a clamp connector that minimizes the effects of external loads and vibrations from the pump systems. 
     It is another object of the present invention to provide a clamp connector that avoids cracks in the connections between flowlines and other components of a hydraulic fracturing system. 
     It is another object of the present invention to provide a clamp connector that does not require metal-to-metal seals. 
     It is another object of the present invention provide a clamp connector that can be reused. 
     It is another object of the present invention to provide a clamp connector that has a more robust sealing action. 
     It is still another object of the present invention to provide a clamp connector that has a substantially greater lifetime of use. 
     It is another object of the present invention to provide a clamp connector that is cost-effective. 
     It is a further object of the present invention to provide a clamp connector that is able to be used at various locations of a flowline. 
     It is a further object of the present invention to provide a clamp connector that avoids damage to seal surfaces. 
     These and other objects and advantages of the present invention will become apparent from a reading of the attached specification and appended claims. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is clamp clamp connection for use with flowlines of a hydraulic fracturing operation. This clamp connection includes a female clamp hub having a seal pocket formed in a face thereof, a male clamp hub having a raised face at an end thereof and having an annular protrusion extending outwardly of the raised face, an elastomeric seal received in the seal pocket of the female clamp hub, and a clamp connector extending around the female clamp hub and the male clamp hub so as to maintain the male clamp hub and the female clamp hub in liquid-tight relationship. The annular protrusion bears against the side of the elastomeric seal. The raised face of the male clamp hub is received an interior of the female clamp hub. 
     The female clamp hub has an end face that bears against end face of the male clamp hub. The female clamp hub and the male clamp of each have an annular flange formed at an outer diameter thereof. The clamp connector is engaged with both of the annular flanges of the female clamp hub and the male clamp hub. The female clamp hub has a recessed area formed inwardly of the end face thereof. The raised face of the male clamp hub is received in the recessed area of the female clamp. The annular protrusion of the male clamp hub extends at least partially into the seal pocket of the female clamp. 
     The elastomeric seal has an anti-extrusion ring at an outer diameter thereof. The annular protrusion bears against this anti-extrusion ring. 
     The female clamp hub and the male clamp hub each have an interior passageway axially aligned with each other. The elastomeric seal has an inner diameter facing the interior passageway of the female clamp hub. The interior passageway of the female clamp hub has a wall and the interior passageway of the male clamp hub has a wall. The inner diameter of the elastomeric seal is generally flush with or recessed from the walls of the male clamp hub and the female clamp hub. 
     In the various embodiments of the present invention, various components can be connected by way of the clamp connection of the present invention. In one embodiment, a swivel joint is connected to the one of the male clamp hub and the female clamp hub and a check valve is connected to another of the male clamp hub and the female clamp hub. In another embodiment, a swivel joint is connected to the one of the male clamp hub and the female clamp hub and a pipe section is connected to another of the male clamp hub and the female clamp hub. In another embodiment of the present invention, a check valve is connected to the one of the male clamp hub and the female clamp hub and a pipe section is connected to another of the male clamp hub and the female clamp hub. In still a further embodiment of the present invention, a first pipe section is connected to one of the male clamp hub and the female clamp hub and a second pipe section is connected to another of the male clamp hub and the female clamp hub. 
     The clamp connector of the present invention includes a first semi-annular member extending around a portion of the annular flanges of the male clamp hub and the female clamp hub and a second semi-annular member extends around another portion of the annular flanges of the male clamp hub and the female clamp hub. The first semi-annular member has bolt holes extending outwardly therefrom. The second semi-annular member has bolt holes extending outwardly therefrom. The bolt holes of the second semi-annular member are axially aligned with the bolt holes of the first semi-annular member. A bolt is received in each of the aligned pairs of bolt holes of the first semi-annular member and the second semi-annular member. The bolt is tightable so as to draw the end faces of the male clamp hub and the female clamp hub together. The annular protrusion applies a compression force against the elastomeric seal when the end faces are drawn together. 
     This foregoing Section is intended to describe, with particularity, the preferred embodiments of the present invention. It is understood that modifications to these preferred embodiments can be made within the scope of the present claims. As such, this Section should not to be construed, in any way, as limiting of the broad scope of the present invention. The present invention should only be limited by the following claims and their legal equivalents. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIG.  1    is a cross-sectional view of the clamp connection of the present invention. 
         FIG.  2    is an exploded view of the clamp connection of the present invention. 
         FIG.  3    is a detailed view showing circled area “ 3 ” of  FIG.  2   . 
         FIG.  4    is an exploded perspective view showing the configuration of the male clamp hub. 
         FIG.  5    is an exploded upper perspective view of the female clamp hub of the present invention. 
         FIG.  6    is an upper perspective view showing the complete assembly of the clamp connection of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIG.  1   , there is shown the clamp connection  10  in accordance with the teachings of the present invention. The clamp connection  10  includes a female clamp hub  12  having a seal pocket  14  formed therein, a male clamp hub  16  having a raised face  18  formed at an end thereof, an elastomeric seal  20  received in the seal pocket  14  of the female clamp hub  12 , and a clamp connector  22  extending around the female clamp hub  12  and the male clamp hub  16  so as to maintain the male clamp hub  16  and the female clamp hub  12  in a liquid-tight relationship. The male clamp hub  16  has an annular protrusion  24  extending outwardly of the raised face  18 . This annular protrusion  24  bears against a side of the elastomeric seal  20 . The raised face  18  of the male clamp hub  16  is received in an interior of the female clamp hub  12 . 
     The female clamp hub  12  has an end face  26  that bears against an end face  28  of the male clamp hub  16 . The female clamp hub has an annular flange  30  formed at an outer diameter thereof. The male clamp hub  16  also has an annular flange  32  formed at an outer diameter thereof. The clamp connector  22  is engaged with both of the annular flanges  30  and  32  of the female clamp hub  12  and the male clamp hub  16 . 
     The female clamp hub  12  has a recessed area  34  formed inwardly of the end face  26  thereof. The raised face  18  of the male clamp hub  16  is received in this recessed area  34  of the female clamp hub  12 . It can be seen that the annular protrusion  24  of the male clamp hub  16  extends at least partially into the seal pocket  14  of the female clamp hub  12 . 
     The elastomeric seal  20  has an anti-extrusion ring  36  at an outer diameter thereof. The annular protrusion  24  bears against this anti-extrusion ring  36 . 
     The female clamp hub  12  has an interior passageway  38 . The male clamp hub  16  also has an interior passageway  40 . The interior passageway  38  of the female clamp hub  12  is axially aligned with the interior passageway  40  of the male clamp hub  16 . The elastomeric seal  24  has an inner diameter  42  that faces the interior passageway  38  of the female clamp hub  12 . The interior passageway  38  of the female clamp hub  12  has a wall  44 . The interior passageway  40  of the male clamp hub  16  also has a wall  46 . The inner diameter  42  of the elastomeric seal  20  is generally flush with or recessed from the walls  44  and  46  of the female clamp hub  12  and the male clamp hub  16 . 
     In normal use, the female clamp hub  12  and the male clamp hub  16  can be joined the various components of a hydraulic fracturing system. In one embodiment, a swivel joint can be connected to one of the male clamp hub  16  and the female clamp hub  12  and a check valve can be connected to another of the male clamp hub  16  and the female clamp hub  12 . In another embodiment, a swivel joint can be connected to one of the male clamp hub  16  and the female clamp hub  12  while a pipe section is connected to another of the male clamp hub  16  and the female clamp hub  12 . In another embodiment, a check valve can be connected to one of the male clamp hub  16  and the female clamp hub  12  while a pipe section can be connected to another of the male clamp hub  16  and the female clamp hub  12 . In still a further embodiment of the present invention, a first pipe section to be connected to one of the male clamp hub  16  and the female clamp hub  12  while a second pipe section is connected to another of the male clamp hub  16  and the female clamp hub  12 . 
       FIG.  1    shows a configuration of a cross-section of the clamp connector  22 . The clamp connector  22  is of a configuration of a clamp connector currently manufactured by Greyloc. This clamp connector includes a first semi-annular member  50  extending around a portion of the annular flanges of the male clamp hub  16  and the female clamp hub  12 . There is a second semi-annular member  52  that extends around another portion of the annular flanges  30  and  32  of the female clamp hub  12  and the male clamp hub  16 . When the first and second semi-annular members  50  and  52  are drawn together, the tapered relationship between the outer surfaces of the flanges  30  and  32  will cause the end faces  26  and  28  to be drawn together in order to create a liquid-tight seal between the female clamp hub  12  and the male clamp hub  16 . When this liquid-tight relationship is achieved, the annular protrusion  24  will exert a compression force against the elastomeric seal  20 . 
     In this configuration of the present invention, the use of the elastomeric seal, as opposed to metal-to-metal seals minimizes the effects of external loads and vibrations associated with pump systems. The elastomeric seal will tend to absorb many of these vibrations so that the vibrations do not pass entirely from one component to another component. This somewhat flexible and shock-absorbing connection avoids cracks in the connection that would otherwise occur by a metal-to-metal seal. The present invention entirely avoids such metal-to-metal seals. The use of the elastomeric seal  20 , along with a clamp connector  22 , allows the clamp connection to be reused. The engagement between the annular protrusion  24  and the elastomeric seal  20  establishes a more robust sealing configuration. The arrangement of the present invention allows the clamp connection to have a longer life than that of metal-to-metal seals. The use of the elastomeric seal  20 , in combination with the annular protrusion  24 , is very cost effective. The configuration of the clamp connection of the present invention allows it to be used in various locations along a flowline. This configuration also avoids damage to the various seal surfaces which could otherwise occur through the use of metal-to-metal seals. 
       FIG.  2    illustrates the relationship between the female clamp hub  12  and the male clamp hub  16 . It can be seen that the female clamp hub  12  includes annular flange  30  extending outwardly therefrom. Male clamp hub  16  has annular flange  32  extending outwardly therefrom. The female clamp hub  32  includes a seal pocket (not illustrated) which is adapted to receive the elastomeric seal  20  therein. The male clamp hub  16  includes a raised face  18  that extends outwardly from the face  28  thereof. The annular protrusion  24  extends outwardly of the raised face  18 . 
       FIG.  3    shows a detailed view of the relationship between the raised face  18  and the annular protrusion  24 . It can be seen that the annular protrusion  24  has an outer diameter slightly less than the outer diameter of the raised face  18 . The raised face  18  has a portion  60  that extends toward the body of the male clamp hub  16 . The raised face  24  will extend into the seal pocket  14  so as to bear against a side of the elastomeric seal  20  in order to provide a strong sealing force thereagainst. 
       FIG.  4    shows a further view of the relationship between the female clamp hub  12  and the male clamp hub  16 . In particular, it can be seen that the raised face  18  extends outwardly of the face  28  of the male clamp hub  16 . The annular protrusion  24  extends slightly outwardly of the raised face  18 . The annular protrusion  24  is generally aligned with the size and diameter of the elastomeric ring  20 . 
       FIG.  5    shows the configuration of the seal pocket  14  of the female clamp hub  12 . The elastomeric ring  20  is received into the interior of the seal pocket  12 . The interior surfaces within the seal pocket  14  will bear against the side of the elastomeric ring  20  so as to provide a strong sealing force thereagainst. The male clamp hub  16  is positioned so as to be aligned with the female clamp hub  12 . 
       FIG.  6    illustrates how the clamp connector  22  is configured so as to join the female clamp hub  12  with the male clamp hub  16 . In particular, the clamp connector  22  includes a first semi-annular member  50  and a second semi-annular member  52  that are positioned over the respective annular flanges  30  and  32  of female clamp connector  12  and male clamp connector  16  in a manner shown in  FIG.  1    hereinabove. The first semi-annular member  50  has bolt holes  62  and  64  extending outwardly therefrom. The second semi-annular member  52  also has bolt holes  66  and  68  extending outwardly therefrom. Bolts  70  and  72  are received in the bolt holes  62  and  66 . Bolts  74  and  76  are received in the bolt holes  64  and  68 . The bolt holes of the first semi-annular member  50  are axially aligned with the bolt holes of the second semi-annular member  52 . The bolts  70 ,  72 ,  74  and  76  are suitably tightenable so as to draw the first and second semi-annular members  50  and  52  together so as to apply a strong force against the annular flanges of the female clamp hub  12  and the male clamp hub  16  in order to draw the end faces together. When this is accomplished, the annular protrusion applies a compression force against the elastomeric seal. 
     The foregoing disclosure and description of the invention is illustrative and explanatory thereof. Various changes in the details of the illustrated construction can be made within the scope of the appended claims without departing from the true spirit of the invention. The present invention should only be limited by the following claims and their legal equivalents.