Patent Publication Number: US-10767445-B2

Title: Valve assembly for downhole pump of reciprocating pump system

Description:
BACKGROUND OF THE DISCLOSURE 
     Reciprocating pump systems, such as sucker rod pump systems, extract fluids from a well and employ a downhole pump connected to a driving source at the surface. A rod string connects the surface driving force to the downhole pump in the well. When operated, the driving source cyclically raises and lowers the downhole plunger, and with each stroke, the downhole pump lifts well fluids toward the surface. 
     For example,  FIG. 1  shows a sucker rod pump system  10  used to produce fluid from a well. A downhole pump  14  has a barrel  16  with a standing valve  24  located at the bottom. The standing valve  24  allows fluid to enter from the wellbore, but does not allow the fluid to leave. Inside the pump barrel  16 , a plunger  20  has a traveling valve  22 , which allows fluid to move from below the plunger  20  to the production tubing  18  above, but does not allow fluid to return from the tubing  18  to the pump barrel  16  below the plunger  20 . A driving source (e.g., a pump jack or pumping unit  26 ) at the surface connects by a rod string  12  to the plunger  20  and moves the plunger  20  up and down cyclically in upstrokes and downstrokes to lift fluid to the surface. 
     Various types of valve assemblies have been used for the standing and traveling valves of a downhole pump. For example,  FIG. 2A  illustrates a one-piece valve assembly  30 A according to the prior art, which can be used for a standing valve or a traveling valve of a downhole pump. The assembly  30 A includes a housing  40  having uphole and downhole ends  44  and  46  with a flow passage  42  therethrough. The ends  44  and  46  have threads for threading to other components of a pump system. An internal cage  50  is integrally machined inside the flow passage  42 . A ball (not shown) inserts in the internal cage  50 , and a seat (not shown) inserts in the flow passage  42  to engage an internal shoulder  55 . A pin-threaded component can then thread to the thread at the housing&#39;s downhole end  46  to retain the seat and ball in the cage  50 . 
     The cage  50  includes a stop  52  to stop the ball and include flutes  54  in the flow passage  42  that allow flow to pass the ball when engaged with the stop  52 . Axial rails or ball guides  56  between the flutes  54  provide support for the ball in its movement. 
     Being integral, the housing  40  and internal cage  50  are composed of the same material. In many cases, they are made of a stainless steel, a nickel-copper alloy, MONEL® metal, or the like. (MONEL is a registered trademark of HUNTINGTON ALLOYS CORPORATION.) It is common to line the rails  56  and even the stop with  52  with a cobalt-chromium alloy, such as a STELLITE® material, to provide hardness for supporting and engaging the ball. (STELLITE is a registered trademark of KENNAMETAL INC.) A welding process, such as tungsten inert gas (TIG) welding, is used to line the hardening alloy on the surfaces, which can be complicated. 
     As can be seen from this example in  FIG. 2A , forming the internal cage  50  and making threads  44 ,  46  requires a considerable amount of machining and manipulation. Coating internal surfaces of the cage  50  with a hard alloy requires additional manufacturing and precision. 
     Rather than a one-piece assembly, multi-piece assemblies can be used. For example,  FIG. 2B  illustrates one type of two-piece valve assembly  30 B according to the prior art, which can be used for a standing valve or a traveling valve of the downhole pump. Again, the assembly  30 B includes a housing  40  having uphole and downhole ends  44  and  46  with a flow passage  42  therethrough. The ends  44  and  46  have threads for threading to other components of a pump system. 
     An insert  60  is separately machined and inserted inside the flow passage  42  to engage its upper end  64  against a shoulder  45 . A ball B inserts in the insert  60 , and a seat  70  inserts in the flow passage  42  to engage the lower end  66  of the insert  60 . To provide sealing, a spacer  72  with a seal  74  fits against the seat  70 . A pin-threaded component can then thread to the downhole end  46  to retain the spacer  72 , the seat  70 , the ball B, and the insert  60 . 
     The insert  60  includes a stop  62  to stop the ball B and includes flutes  65  in the flow passage  42  that allow flow to pass the ball B when engaged with the stop  62 . Axial rails or ball guides  67  between the flutes  65  provide support for the ball B in its movement. Because the insert  60  is a separate component, it can be made of a different material than the housing  40  and can be made, for example, of a STELLITE® material. 
     The spacer  72  and the seal  74  are needed because fluid can leak past the end  66  of the insert  60  engaged on the seat  70  and can leak around the outside of the seat  70 . For example, if the assembly  30 B is used as a traveling valve in a downhole pump, fluid at higher pressure in the plunger during an upstroke may leak to the lower pressure of the barrel. This leakage, if allowed to enter the threads at the downhole end  46 , can erode the threads of the pump during operation. The spacer  72  with the seal  74  helps reduce leakage. 
     The components of the insert  60 , the seat  70 , and the spacer  72  are all sandwiched against the shoulder  45  by the threading of an adapter at the housing&#39;s downhole end  46 . This can produce compressive load on the insert  60 , which can lead to distortion and failure. For this reason, this insert  60  has an increased wall thickness to handle the compressive load, which requires the assembly  30 B to be used with a ball B smaller than a standard API-sized ball. 
       FIG. 2C  illustrates another type of two-piece valve assembly  30 C according to the prior art, which can be used for a standing valve or a traveling valve of the downhole pump. This assembly  30 C is for use with a standard API-sized ball. Again, the assembly  30 C includes a housing  40  having uphole and downhole ends  44  and  46  with a flow passage  42  therethrough. The ends  44  and  46  have threads for threading to other components of a pump system. 
     An insert  60  is separately machined and inserted inside the flow passage  42  to engage its lower end  66  against a shoulder  45 . To retain the insert  60  and provide sealing, a gasket  63  is placed on the upper end of the insert  60 , and an adapter  41  of the housing  40  threads to the uphole threads  44 . To complete the assembly, a ball (not shown) inserts in the insert  60 , and a seat (not shown) inserts in the flow passage  42  to engage the shoulder  45 . A pin-threaded can then thread to the thread at the housing&#39;s downhole end  46  to retain the seat and ball in the housing  40 . 
     The insert  60  includes a stop  62  to stop the ball and include flutes  65  in the flow passage  42  that allow flow to pass the ball when engaged with the stop  62 . Axial rails  67  between the flutes  65  provide support for the ball. Because the insert  60  is a separate component, it can be made of a different material than the housing  40  and can be made, for example, of a STELLITE® material. 
     Because the insert-style assemblies  30 B-C of  FIGS. 2B-2C  require the insert  60  to be both securely captivate and sealed in the flow passage  42 , the typical method is to incorporate additional threaded members and to tighten them to sandwich the insert  60  against a housing shoulder  45 . The compressive load placed on the insert  60  can lead to increased chances of failure and can disport its shape. For these and other reasons, such insert-style design has its drawbacks such as leaking, high temperature limitations, and manufacturing costs. 
     The subject matter of the present disclosure is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above. 
     SUMMARY OF THE DISCLOSURE 
     A method is disclosed of assembling a valve assembly of a downhole pump for a reciprocating pump system. The method comprises: inserting an insert in a flow passage of a housing. To position the insert, a charge of the metallic material can be initially positioned in a circumferential groove about the insert. 
     The housing has first and second ends and defines the flow passage therethrough. The flow passage defines a surface between the first and second ends, and the insert has third and fourth ends allowing for flow therethrough. The third end defines a ball stop, and the fourth end has a ball passage. 
     The method further comprises setting one of the third and fourth ends of the insert against the surface in the flow passage; and securing the insert in the housing by metallurgically affixing between at least a portion of the insert and the flow passage. 
     The method can further comprise positioning a ball movably disposed in the flow passage of the housing, engagable with the ball stop of the insert, and passable at least partially through the ball passage of the insert and can even further comprise positioning a ball seat in the flow passage adjacent the fourth end of the insert having the ball passage. To position the ball seat in the flow passage, for example, the ball seat can abut against the fourth end or can abut against an opposite side of the surface against which the fourth end abuts. Finally, the method can further comprise attaching the first end of the housing to a plunger of the downhole pump or to a barrel of the downhole pump. 
     The housing can be initially formed by machining the flow passage in the housing to define the surface between the first and second ends and by machining threads at the first and second ends for threading to other components of the downhole pump. The insert can be initially formed by casting the insert with the ball stop and the ball passage. 
     To machine the flow passage in the housing to define the surface between the first and second ends, the method can comprise forming a rim, a lip, a detent, a stop, or a shoulder in the flow passage, forming an inwardly angled portion of a sidewall of the flow passage, or forming a cylindrical portion of the sidewall of the flow passage. 
     A number of steps can be used to set the one of the third and fourth ends of the insert against the surface and to metallurgically affix between at least the portion of the insert and the flow passage. In particular, the steps involve: (i) engaging the third end of the insert against the surface, and metallurgically affixing between at least a portion of the fourth end of the insert and the flow passage; (ii) engaging the fourth end against the surface, and metallurgically affixing between at least a portion of the third end of the insert and the flow passage; (iii) engaging the third end of a body of the insert against the surface, inserting a spacer of the insert separate from the body toward the second end of the housing, and metallurgically affixing between at least a portion of the spacer and the flow passage; (iv) engaging the fourth end of a body of the insert against the surface, inserting a spacer of the insert separate from the body toward the first end of the housing, and metallurgically affixing between at least a portion of the spacer and the flow passage; or (v) engaging one of the third and fourth ends of the insert against the surface, and metallurgically affixing between at least a portion of both of the third and fourth ends of the insert and the flow passage. 
     To metallurgically affix between at least the portion of the insert and the flow passage, the method can comprise brazing with a brazing material between at least the portion of the insert and the flow passage. A charge of the brazing material can be initially positioned adjacent an annular space between the insert and the flow passage and applying heat adjacent the brazing material. The charge of the brazing material can be positioned in a circumferential slot around the insert. The heat can be applied using inductive heating with a coil disposed relative to the housing. 
     To metallurgically affix between at least the portion of the insert and the flow passage, the method can comprises soldering with a soldering material between at least the portion of the insert and the flow passage; or solid-state joining at least the portion of the at least one of the third and fourth ends of the insert in the flow passage. 
     According to the present disclosure, a downhole pump for a reciprocating pump system having a rod string disposed in a tubing string comprises a valve assembly assembled according to the method of disclosed above. 
     A valve assembly is disclosed for a downhole pump. The assembly comprises: a housing disposed on the pump, the housing having first and second ends and defining a flow passage therethrough, the flow passage defining a surface between the first and second ends; and an insert disposed in the housing, the insert having third and fourth ends allowing for flow therethrough, the third end defining a ball stop, the fourth end having a ball passage, at least one of the third and fourth ends engaging the surface of the housing, at least a portion of the insert metallurgically affixed to the flow passage. 
     The first end of the housing can define first threads for threading to a first component of the downhole pump, and the second end of the housing can define second threads for threading to a second component of the downhole pump. 
     A number of arrangements of the insert can be used. The third end of the insert can engage the surface, and at least a portion of the fourth end of the insert is metallurgically affixed to the flow passage. Alternatively, the fourth end of the insert can engage the surface, and at least a portion of the third end of the insert is metallurgically affixed to the flow passage. 
     In other arrangements, the third end of the insert can comprise a body of the insert engaging the surface, and the fourth end of the insert can comprise a spacer separate from the body of the insert. The spacer is disposed against the body and being metallurgically affixed in the flow passage. Alternatively, the fourth end of the insert can comprise a body of the insert engaging the surface, and the third end of the insert can comprise a spacer separate from the body of the insert. The spacer is disposed against the body and being metallurgically affixed in the flow passage. In a further alternative, the one of the third and fourth end of the insert can engage the surface, and at least a portion of both of the third and fourth ends of the insert are metallurgically affixed to the flow passage. 
     The assembly further comprises: a ball seat disposed in the flow passage adjacent the fourth end having the ball passage; and a ball movably disposed in the flow passage of the housing, engagable with the ball stop of the insert, passable at least partially through the ball passage of the insert, and seatable in the ball seat. 
     The ball seat can abut against the fourth end of the insert or can abut against an opposite side of the surface against which the fourth end of the insert abuts. The insert can define a circumferential groove thereabout and comprises a charge of metallic material therein. The flow passage can define an annular groove therein, wherein the insert has a charge of metallic material disposed thereon and positioned adjacent the annular groove. 
     The metallurgical affixation and the surface can secure the insert in the flow passage without compressive load across the third and fourth ends of the insert. Moreover, the metallurgical affixation can seal the insert in the flow passage preventing flow through an annular space between the insert and the flow passage. 
     A number of forms of metallurgical affixation can be used. In particular, a brazing material can braze at least the portion of the at least one of the third and fourth ends of the insert in the flow passage. In general, the housing can comprise a nickel-copper alloy; the insert can comprise a cobalt-chromium alloy; and the brazing material can comprise a silver-based alloy. In other arrangements, a soldering material can solder at least the portion of the at least one of the third and fourth end of the insert in the flow passage, or a solid-state weldment can join at least the portion of the at least one of the third and fourth ends of the insert in the flow passage. 
     A downhole pump is disclosed herein for a reciprocating pump system having a rod string disposed in a tubing string. The pump comprises: a barrel coupling to the tubing string and having a standing valve assembly; and a plunger coupling to the rod string and movably disposed in the barrel, the plunger having a traveling valve assembly. At least one of the standing and traveling valve assemblies comprises a valve assembly as disclosed above. 
     The foregoing summary is not intended to summarize each potential embodiment or every aspect of the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates an example of a reciprocating rod pump system known in the art. 
         FIG. 2A  illustrates a one-piece valve assembly according to the prior art. 
         FIG. 2B  illustrates one type of two-piece valve assembly according to the prior art. 
         FIG. 2C  illustrates another type of two-piece valve assembly according to the prior art. 
         FIG. 3  illustrates a downhole pump of a reciprocating pump system according to the presented disclosure. 
         FIGS. 4A-4C  illustrate different sectional views of a first type of a valve assembly for the downhole pump of  FIG. 3   
         FIGS. 5A-5B  illustrate sectional views of valve components during a stage of manufacture of the first type of valve assembly of the present disclosure. 
         FIGS. 5C-5D  illustrate details of the valve components in  FIGS. 5A-5B . 
         FIGS. 6A-6B  illustrate sectional views of valve components during a stage of manufacture of a second type of valve assembly of the present disclosure. 
         FIGS. 6C-6D  illustrate details of the valve components in  FIGS. 6A-6B . 
         FIGS. 7A-7B  illustrate sectional views of valve components during a stage of manufacture of a third type of valve assembly of the present disclosure. 
         FIGS. 8A-8B  illustrate sectional views of valve components during a stage of manufacture of a fourth type of valve assembly of the present disclosure. 
         FIG. 9  illustrates a sectional view of valve components during a stage of manufacture of a fifth type of valve assembly of the present disclosure. 
         FIG. 10  illustrates a sectional view of valve components during a stage of manufacture of a sixth type of valve assembly of the present disclosure. 
         FIGS. 11A-11D  illustrate a number of variations for setting the insert inside the flow passage of the housing. 
         FIG. 12  illustrates a process of manufacturing a valve assembly of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE DISCLOSURE 
       FIG. 3  illustrates a downhole pump  70  of a reciprocating pump system according to the presented disclosure. The downhole pump  70  has a stationary assembly having a barrel  72  connected to a seating assembly  74  and a top outlet  76 . Various types of seating assemblies  74  can be used, and the one shown is only provided as an example. A standing valve assembly  92  is located at the bottom of the barrel  72 . The standing valve assembly  92 , which includes a cage, a ball, and a seat, allows fluid to enter the barrel  72  from a wellbore, but does not allow the fluid to leave. 
     A traveling assembly  80  connects at a coupling  82  to a rod string (not shown) used for reciprocating the traveling assembly  80 . A rod  84  extends from the coupling  82  to a ported coupling  86  connected to a plunger  88 , which is movably disposed in the barrel&#39;s internal chamber  75 . The plunger  88  has a traveling valve assembly  90 , which includes a cage, a ball, and a seat. The traveling valve assembly  90  allows fluid to enter from below the plunger  88 , but does not allow fluid to leave. 
     As will be appreciated, the lengths of the barrel  72 , rod  84 , plunger  88  and the like are not shown to relative scale in  FIG. 3  representative of the stroke of the pump  70 . In any event, during the upstroke, the traveling valve assembly  90  is closed, and any fluid above the plunger  88  is lifted towards the outlet  76 . Meanwhile, the standing valve assembly  92  opens and allows fluid to enter the pump barrel  72  from the wellbore. During the downstroke, the traveling valve assembly  90  is opened, and the standing valve assembly  92  closes. Previously drawn fluid in the barrel  72  can then enter through the traveling valve  90  to above the plunger  88 . 
     The traveling valve assembly  90  and/or the standing valve assembly  92  use a valve assembly according to the present disclosure. Several configurations for the valve assemblies are disclosed below. 
     Turning to  FIGS. 4A-4C , different sectional view of a valve assembly  100  for the downhole pump of  FIG. 3  are shown. The valve assembly  100  includes a housing  110 , an insert  120 , a ball  130 , and a seat  140 . The housing  110  has first and second ends  114 ,  116  and defines a flow passage  112  therethrough. Internally, the flow passage  112  defines a surface  115  between the ends  114 ,  116 . (The surface  115  here is a shoulder defined in the flow passage  112 , but as will be detailed below, use of a shoulder is not strictly necessary. For example, the surface  115  can be a rim, lip, detent, stop, or the like. The surface  115  can be an angling of the sidewall to create an interference fit, or the surface  115  may simply be a point on the cylindrical sidewall of the flow passage  112 .) As is typical, the ends  114 ,  116  have threads for threading to other components of the pump assembly. As shown here, the ends  114 ,  116  include box threads, but either one or both could be pin threads depending on the location of the valve assembly. 
     The insert  120  has ends  124 ,  126  allowing for flow therethrough. The upper end  124  defines a ball stop  125 , and the lower end  126  defines a ball passage  127 . Axial rails  123  divided by flutes  123 ′ connect between the ends  124 ,  126 . The rails  123  support the axial movement of the ball  130 , while the flutes  123 ′ allow for flow around the ball  130 . The insert  120  can be a unitary piece as shown or can comprise more than one piece in an assembly. For example, as disclosed below, the insert  120  can comprise a body having the ball stop, and a spacer defining at least portion of the ball passage. 
     At least one of the ends  124 ,  126  engages the surface or shoulder  115 , which in this case is the upper end  124 . Here, the seat  140  inserts against the lower end  126  of the insert  120  and is held in place by an adapter  102  threaded to the thread of the downhole end  116  of the housing  110 . The ball  130  is movable in the insert  120  to engage the stop  125  or to seat in the seat  140 . 
     The insert  120  secures in the flow passage  112  with metallic material  150  metallurgically affixed between the flow passage  112  and at least a portion of the insert  120 . As shown here, the metallic material  150  metallurgically affixes the lower end  126  of the insert  120  to the flow passage  112 . This securing produces a seal that helps prevent fluid leakage from passing in the annulus between the insert  120  and the flow passage  112 , which could leak past the seat  140  and potentially erode the thread at the connection of the housing&#39;s end  116  to the adapter  102 . 
     The metallic material  150  can be comprised of a number of materials and can be metallurgically affixed in a number of ways. In one arrangement, the material  150  comprises a brazing material that metallurgically affixes between portion of the insert  120  and the flow passage  112  using a brazing process. In another arrangement, the material  150  comprises a soldering material that metallurgically affixes between portion of the insert  120  and the flow passage  112  using a soldering process. In yet another arrangement, the material  150  comprises weldment material that metallurgically affixes between portion of the insert  120  and the flow passage  112  using a solid state joining process. Variations of these are disclosed further below. 
     Once assembled, the metallic material  150  of the metallurgical affixing and the surface or shoulder  115  secure the insert  120  in the flow passage  112  without (or with at least reduced) compressive load across the insert&#39;s ends  124 ,  126 . As noted, compressive load on the insert  120  could distort its shape and lead to premature failure. Additionally, the metallic material  150  seals the insert  120  in the flow passage  112  preventing flow through an annular space between the insert  120  and the flow passage  112 . This sealing can help in preventing fluid leakage from damaging other components of a downhole pump, such as the threaded ends of the various components. 
       FIGS. 5A-5B  illustrate sectional views of valve components during a stage of manufacture of this first type of valve assembly  100  of the present disclosure, such as the assembly  100  of  FIGS. 4A-4C . Similar reference numbers are used for the same components between configurations. 
     In the manufacture, the insert  120  installs in the flow passage  112  with the upper end  124  engaging the surface or shoulder  115  near the uphole end  114  of the housing  110 . If the surface  115  is a shoulder as shown, then the location of the insert  120  can be well-defined in the flow passage  112  for fitting additional components of seat, adapters, and the like. If another type of surface  115  is used, then the location of the insert  120  can be defined by a temporary fixture used in the flow passage  112  during assembly, such as during brazing or soldering as disclosed herein. This can allow the ends of the insert  120  to be properly spaced in the flow passage  112  for eventual coupling of the housing  110  to other components of the assembly. 
     A charge  151  of metallic material is positioned at the lower end  126  of the insert  120 , and heating is applied to melt the charge  151  to form the metallurgical affixing between the lower end  126  of the insert  120  and the flow passage  112 . An additional charge (not shown) of a brazing material could be used between the insert&#39;s upper end  124  and the surface or shoulder  115  if suitable. 
     The heating can be supplied by a heating appliance H. (Although not shown, the assembly  100  may be inverted so that gravity facilitate the wicking of the metallurgical affixing between the lower end  126  of the insert  120  and the flow passage  112 .) 
     As shown specifically here, the charge  151  can be a ring, strip, coil or the like of metallic material, which can be soldering or brazing material. For soldering, the heating appliance H can heat the charge  151  of soldering material. For brazing, the heating appliance H can be an inductive coil disposed relative to the housing  110  to heat the charge  151  of brazing material. For friction welding, heating can also be used. In any of these arrangements, the heating appliance H can be disposed about and/or inside the housing  110 . The heating can be performed in a number of ways, such as using an inductive coil, an oven, a heating torch or the like. 
     As best shown in the detail of  FIG. 5C , a beveled edge  128  can be provided on the insert&#39;s lower end  126  to facilitate the placement of the charge  151  and wicking of the affixing material. As best shown in  FIG. 5D , an inner annular slot  113  can be defined in the flow passage  112  of the housing  110  and/or an outer annular slot  129 ′ can be defined around the outside of the insert&#39;s lower end  126  to facilitate the placement and wicking of the affixing material. 
     Once the insert  120  is metallurgically affixed, the configuration of  FIGS. 5A-5B  would then be assembled in a similar way to the assembly of  FIGS. 4A-4C  to include the seat (not shown) at the insert&#39;s lower end  126  and to include an adapter (not shown) at the housing&#39;s downhole end  116 . 
     Although the housing  110  has the surface or shoulder  115  toward the uphole end  114  against which the upper end  124  of the insert  120  rests so the insert  120  can secure with the material  150  at the lower end  126 , a reverse arrangement could be used. Thus, the housing  100  can instead have the surface or shoulder  115  toward the downhole end  116  against which the lower end  126  of the insert  120  rests so the insert  120  can secure with the material  150  at the upper end  124  of the insert  120 . 
     Turning to  FIGS. 6A-6B , for example, sectional views of valve components are illustrated during a stage of manufacture of a second type of valve assembly  100  of the present disclosure. Similar reference numbers are used for the same components between configurations. 
     In the manufacture, the insert  120  installs in the flow passage  112  with the lower end  126  engaging the surface or shoulder  115  near the downhole end  116  of the housing  110 . A charge  151  of metallic material is positioned at the upper end  124  of the insert  120 , and heating is applied to melt the charge  151  to form the metallurgical affixing between the upper end  126  of the insert  120  and the flow passage  112 . As before, the heating can be supplied by a heating appliance or inductive coil H. 
     As shown specifically here, the charge  151  can be a ring, strip, coil or the like of metallic material, which can be soldering or brazing material. As best shown in the detail of  FIG. 6C , a circumferential slot  129  can be provided on the insert&#39;s upper end  124  to facilitate the placement of the charge  151  and wicking of the affixing material. As best shown in  FIG. 6D , an inner annular slot  113  can be defined in the flow passage  112  of the housing  110  to facilitate the placement and wicking of the affixing material. 
     Once the insert  120  is metallurgically affixed, the configuration of  FIGS. 6A-6B  would then be assembled to include the seat (not shown) against the opposite side of the surface or shoulder  115  and to include a lower adapter (not shown) at the housing&#39;s downhole end  116 . An upper adapter, plunger, barrel, or other component (not shown) can then be threaded at the housing&#39;s uphole end  114 . 
     In the above configurations, the insert  120  has provisions to accept the charge  151 . In alternative configurations, a “spacer” element of the insert  120  having such provisions can be used adjacent to a body of the insert  120 . Turning to  FIGS. 7A-7B , for example, sectional views of valve components are illustrated during a stage of manufacture of a third type of valve assembly  100  of the present disclosure. Similar reference numbers are used for the same components between configurations. 
     In the manufacture, the insert  120  includes a body  121  and a spacer  160  that install in the flow passage  112  with the insert&#39;s upper end  124  engaging the surface or shoulder  115  near the uphole end  114  of the housing  110 . If suitable, an additional charge (not shown) of a brazing material could be used between the insert&#39;s upper end  124  and the surface or shoulder  115 . 
     The spacer  160  of the insert  120  has a charge  151  of metallic material, and the spacer  160  is positioned at the lower end  126  of the body  121  of the insert  120 , and heating is applied to melt the charge  151  to form the metallurgical affixing between the spacer  160  and the flow passage  112 . As before, the heating can be supplied by a heating appliance or inductive coil (not shown). 
     As shown specifically here, the charge  151  can be a ring, strip, coil or the like of metallic material, which can be soldering or brazing material. As shown, a circumferential slot  169  can be provided around the spacer  160  and an annular slot  113  can be defined inside the flow passage  112  to facilitate the placement and wicking of the affixing material. 
     Once the insert  120  is metallurgically affixed, the configuration of  FIGS. 7A-7B  would then be assembled. An upper adapter (not shown) can then be threaded at the housing&#39;s uphole end  114 . In one arrangement, the passage  162  in the spacer  160  may actually form the seat  165  for the ball (not shown). As expected, this would require insertion of the ball prior to the metallurgical affixing process. A lower adapter (not shown) could then connect at the housing&#39;s downhole end  116 . 
     In alternative arrangement, the spacer  160  may include a larger passage  162  than shown, and the configuration could be assembled to include the seat (not shown) against the spacer  160  and to include a lower adapter (not shown) at the housing&#39;s downhole end  116 . Gaskets (not shown) may be used for additional sealing. 
     Turning to  FIGS. 8A-8B , sectional views of valve components are illustrated during a stage of manufacture of a fourth type of valve assembly  100  of the present disclosure. This is a reverse of the previous arrangement, and similar reference numbers are used for the same components between configurations. 
     In the manufacture, the insert  120  installs in the flow passage  112  with the lower end  126  engaging the surface or shoulder  115  near the downhole end  116  of the housing  110 . If suitable, an additional charge (not shown) of a brazing material could be used between the insert&#39;s lower end  126  and the shoulder  115 . 
     A spacer  160  has a charge  151  of metallic material. The spacer  160  is positioned at the upper end  124  of the insert  120 , and heating is applied to melt the charge  151  to form the metallurgical affixing between the spacer  160  and the flow passage  112 . 
     As shown specifically here, the charge  151  can be a ring, strip, coil or the like of metallic material, which can be soldering or brazing material. As shown, a circumferential slot  169  can be provided around the spacer  160  and an annular slot  113  can be defined inside the flow passage  112  to facilitate the placement and wicking of the affixing material. 
     Once the insert  120  is metallurgically affixed, the configuration of  FIGS. 8A-8B  would then be assembled to include an upper adapter (not shown) threaded at the housing&#39;s uphole end  114 . The seat (not shown) would install against the other side of the shoulder  115 , and a lower adapter (not shown) would thread at the housing&#39;s lower thread  116 . Gaskets (not shown) may be used for additional sealing. 
     Turning to  FIG. 9 , a sectional view of valve components are illustrated during a stage of manufacture of a fifth type of valve assembly  100  of the present disclosure. Similar reference numbers are used for the same components between configurations and are not described again. In contrast to the previous configurations, the insert  120  metallurgically affixes at both ends  124  and  126  inside the flow passage  112 . For example, a bevel  128  at the lower end  126  receives a charge  151  of metallic material to affix to the passage  112 . The upper end  124  includes a circumferential slot  129  for another charge  151 ′ of metallic material to affix to the passage  112 . Heating applied as before could then melt the affixing material of the charges  151 ,  151 ′ to both secure and seal the insert in the flow passage  112 . 
     As shown here, the upper end  124  engages against the surface or shoulder  115 , although an opposite arrangement could be used. As will be appreciated by the present example as well as previous ones, the insert  120  of the present disclosure can be metallurgically affixed inside the flow passage  112  in one or more locations. 
       FIG. 10  illustrates a sectional view of valve components during a stage of manufacture of a sixth type of valve assembly  100  of the present disclosure. Similar reference numbers are used for the same components between configurations and are not described again. In contrast to the previous configurations, the insert  120  metallurgically affixes inside the flow passage  112  with a weldment of metallic material  150 , which also produces the desired seal. The weldment of the metallic material  150  is composed of the solid-state joining of the two existing metallic materials from the housing  110  and the insert  120  so that no additional charge of material is needed (although it could be). 
     As shown on the left side of the figure, the lower end  126  of the insert  120  includes an outwardly protruding lip  157 , and the flow passage  112  includes a complementary shoulder  117 . During assembly as the insert  120  is inserted into the flow passage  112  so that the upper end  124  engages the shoulder  115 , a solid state joining process, such as friction welding, creates the resulting weldment of the metallic material  150  between the insert  120  and the flow passage  112 . The friction welding may alternatively or additionally form a resulting weldment of the metallic material  150 ′ between the insert  120  and the shoulder  115 , as also depicted. 
     To perform the friction welding, one or both of the housing  110  and the insert  120  are rotated so that the lip  157  and shoulder  117  weld together (as well as the fend  124  and the shoulder  115  if appropriate). Inductive heating can also be applied during the process. As will be appreciated in the friction welding process, a number of considerations are necessary, such as the types of material used, which of the housing and/or insert  120  is rotated, what dimensions are needed for the engaging lip  157  and shoulder  117  to make the desired weldment, what fixtures are needed to support the insert  120 , and the like. 
       FIGS. 11A-11D  illustrate a number of variations for setting the insert  120  inside the flow passage  112  of the housing  110 . As noted previously, the surface  115  against which either the upper or lower end  124 ,  126  of the insert  120  is set can be a shoulder defined in the flow passage  112 . As already hinted to above, use of a shoulder is not strictly necessary. For example, a feature such as a rim, a lip, a detent, a stop, or the like can be used. Moreover, the surface  115  can be an angling of the sidewall to create an interference fit, or it may simply be a point on the cylindrical sidewall of the flow passage  112 . 
     For example,  FIG. 11A  shows the insert  120  set inside the flow passage  112  for metallurgically affixing therein (in this case using a charge  151  for brazing the lower end  126  to the flow passage  112 ). Instead of the upper end  124  engaging a protruding shoulder, the upper end  124  sets against or engages at a point on the surface  115  of the cylindrical sidewall of the flow passage  112 . The metallurgical affixing disclosed herein can be sufficient to axially support the insert  120  in the flow passage  112  even under high compressive loads. 
     In the example of  FIG. 11B , the insert  120  sets inside the flow passage  112  for metallurgically affixing therein (in this case using a charge  151  for brazing the upper end  124  to the flow passage  112 ). Instead of the lower end  126  engaging a protruding shoulder, the lower end  126  sets against or engages at a point on the surface  115  of the cylindrical sidewall of the flow passage  112 . 
     In the example of  FIG. 11C , the insert  120  sets inside the flow passage  112  for metallurgically affixing therein (in this case using charges  151  for brazing the upper and lower ends  124 ,  126  to the flow passage  112 ). Instead of the lower end  126  engaging a protruding shoulder, the ends  124 ,  126  set against or engage at points on the surface  115  of the cylindrical sidewall of the flow passage  112 . 
     In the example of  FIG. 11D , the insert  120  sets inside the flow passage  112  for metallurgically affixing therein (in this case using a charge  151  for brazing the lower end  126  to the flow passage  112 ). Instead of the upper end  124  engaging a protruding shoulder, the end  124  sets against or engage at an inwardly angled surface  115  of the sidewall of the flow passage  112 . A reverse arrangement could be used, and brazing at both ends of the insert  120  could be performed. 
     Although not shown in  FIGS. 11A-11D , it will be appreciated that any of the arrangements of the insert  120  having a body  121  and a spacer  160  can be similarly configured. In fact any of the arrangements having a body  121  and a spacer  160  for the insert  120 , one or both ends of the insert&#39;s body  121  can be metallurgically affixed in the flow passage  112  in addition to the metallurgical affixing of the spacer  160 . 
       FIG. 12  illustrates a process  200  of manufacturing a valve assembly  100  of the present disclosure. (For understanding, reference will be made to components of the various configurations of valve assembly  100  discussed above.) 
     In the manufacture, the housing  110  and the insert  120  are formed (Blocks  210 ,  220 ). In particular, the housing  110  is machined to have the flow passage  112 , the shoulder  115 , and any internal grooves  113 , or the like. The threads are formed on the ends  114 ,  116 . 
     For its part, the insert  120  may be machined or may be cast from a suitable material, such as a STELLITE® material. The insert  120  is formed for flow therethrough and to have a ball stop  125 , a ball passage  127 , axial rails  123 , flutes  123 ′, and the like. If the insert  120  is made of a material other than a STELLITE® material or the like, various surfaces can be treated with hardened material in a welding process. 
     In preparation of assembly (Block  230 ), the housing  110  and the insert  120  are cleaned. If brazing or soldering is used, flux is applied to surfaces as needed. 
     For assembly, the insert  120  is inserted in the flow passage  112  of the housing (Block  240 ), and one of the ends  124 ,  126  is set against the shoulder  115  (Block  250 ), depending on the configuration. 
     The insert  120  is then secured in the housing  110  using brazing, soldering, or solid state joining (friction welding). In these steps, any charge  151  of the metallic material for brazing or soldering may be added to the end(s) of the insert  120  and/or the spacer  160  (if used), or the charge  151  may have already been disposed in any circumferential groove on the insert  120  and/or spacer before insertion into the flow passage  112 . For friction welding, a charge  151  may not be used. 
     For brazing and soldering, heating is applied to the housing  110  and the insert  120 . Heating can also be used for friction welding. For example, inductive heating can be applied by coils fit externally about the housing  110  at the location(s) of the charge(s)  151  or the joining surfaces for friction weldment. 
     The process  200  now metallurgically affixes the metallic material  150  between the flow passage  112  and at least a portion of the insert  120  (Block  270 ). To complete the assembly at any time after the manufacture, a ball  130  can be movably disposed in the flow passage  112  (Block  280 ) so that the ball  130  will be engagable with the ball stop  125  and passable through the ball passage  127 . The ball seat  140  is then positioned in the flow passage adjacent the ball passage  127  of the insert  120  (Block  280 ). The additional components, such as adapters, are then threaded to the ends  114 ,  116  of the housing  110 , and the assembly  100  can be added to other components of a downhole pump, such as a plunger body or barrel body. 
     In the metallurgically affixing of Step  270 , for example, the upper end  124  of the insert  120  engages against the shoulder  115  as in  FIG. 5A . The metallic material  150  can then metallurgically affix between the flow passage  112  and the lower end  126  of the insert  120 . Alternatively, the lower end  126  can engage against the shoulder  115 , for example, as in  FIG. 6A . The metallic material  150  can then metallurgically affix the between the flow passage  112  and the upper end  124  of the insert  120 . 
     Alternatively, for example, the insert&#39;s upper end  124  can engage against the shoulder  115 , and a spacer separate from a body of the insert  120  can be inserted at the lower end  126 , as in  FIG. 7A . The metallic material  150  can then metallurgically affix between the flow passage  112  and the spacer  160 . Alternatively, for example, the lower end  126  can engage against the shoulder  115 , and a spacer  160  separate from a body  121  of the insert  120  can be inserted at the upper end  124 , as in  FIG. 8A . The metallic material  150  can then metallurgically affix between the flow passage  112  and the spacer  160 . Further still, both upper and lower ends  124 ,  126  can be metallurgically affixed, as in  FIGS. 9-10 . 
     According to various configurations disclosed above, the insert  120  is secured to the housing  110  by means of brazing. This process can ensure that the insert  120  is sealed as well as permanently secured to the housing  110 . A complete housing  110  is machined prior to placing and brazing the insert  120  therein. This form of assembly translates into shorter lead times and lower manufacturing costs. Depending on the materials used, several factors are configured for performing this process, such as the brazing material composition, the orientation of the insert (parallelism and flatness between the cage body axis is desired), flux type, amount of brazing material used (there needs to be a certain shear load carried by the brazed joint), and the brazing method. 
     According to the present disclosure, for example, the metallurgically affixing of the metallic material  150  between the flow passage  112  and at least a portion of the insert  120  can involve brazing a charge  151  of brazing material for the metallic material  150  between the flow passage  112  and at least the portion of the insert  120 . The brazing material is positioned adjacent an annulus between the flow passage  112  and the insert  120 , such as against the end of the insert  120 , in a beveled edge  128 , in a circumferential slot  129 , or the like. Application of the heating to the housing  110  using an inductive coil H adjacent the brazing material then melts the brazing material, which wicks in the annular space and cools to secure and seal. 
     The brazing material used can be any suitable alloy for the application at hand and can be composed of a silver-based braze suited for 300-series stainless steels. For use with a STELLITE® insert  120  and housing  110  of MONEL® material, stainless steel or the like, the brazing material can be a sliver brazing filler metal having various combinations of silver Ag, copper Cu, zinc Zn, cadmium Cd, nickel NI, tin Sn, lithium Li, manganese Mn, and other elements. 
     A particularly useful brazing material may include by weight percent about 50% Ag±1%, 20% Cu±1%, 28% Zn±2%, and 2% Ni±0.5%. The general chemical composition of the brazing material can include AWS classification of BAg-24 (UNS P07505). Other commercially available brazing materials can be used, such as SILVALOY® 505 manufactured by Lucas-Milhaupt, Inc. or STAY-SILV® 50N manufactured by Harris Products Group. (SILVALOY® is a registered trademark of LUCAS-MILHAUPT WARWICK LLC, and STAY-SILV® is a registered trademark of LINCOLN GLOBAL, INC.) 
     The flux can be a black brazing flux for use with high silver brazing filler metals. Black flux turns transparent close to the brazing application temperature, which may be in the range of about 1000-1700° F. One useful flux includes STAY-SILV® black paste flux. 
     According to the present disclosure, the metallurgically affixing of the metallic material  150  between the flow passage  112  and at least a portion of the insert  120  can involve soldering a charge  151  of soldering material for the metallic material  150  between the flow passage  112  and at least the portion of the insert  120 . The soldering material is positioned adjacent an annulus between the flow passage  112  and the insert  120 , such as against the end of the insert  120 , in a beveled edge  128 , in a circumferential slot  129 , or the like. Application of the heating to the housing  110  adjacent the soldering material then melts the soldering material, which wicks in the annular space and cools to secure and seal. Soldering may be suited for lower temperature applications because the solder may have a lower melting point of 500-F or the like. The soldering material used can be any suitable alloy for the application at hand and can be composed of silver and tin. A suitable soldering material would include Stay Brite #8 tin/silver solder, which has a weight percent of 5.5 to 6% silver and a remaining weight percent of tin. ASTM classification for this solder material is B32 Grade Sn95. 
     According to the present disclosure, the metallurgically affixing of the metallic material  150  between the flow passage  112  and at least a portion of the insert  120  can involve a solid state weldment of the material of the housing  110  and the insert  120 . In the solid-state joining process, the housing  110  and the insert  120  can be composed of the same (or similar materials) or can be composed of different materials, such as MONEL® and STELLITE®. As will be appreciated, friction welding dissimilar materials such as MONEL® and STELLITE® would require proper parameters to be defined and may require some pre-heating to be perform. Application of inductive heating to the housing  110  can facilitate the solid-state joining process of spinduction. 
     The foregoing description of preferred and other embodiments is not intended to limit or restrict the scope or applicability of the inventive concepts conceived of by the Applicants. It will be appreciated with the benefit of the present disclosure that features described above in accordance with any embodiment or aspect of the disclosed subject matter can be utilized, either alone or in combination, with any other described feature, in any other embodiment or aspect of the disclosed subject matter. 
     In exchange for disclosing the inventive concepts contained herein, the Applicants desire all patent rights afforded by the appended claims. Therefore, it is intended that the appended claims include all modifications and alterations to the full extent that they come within the scope of the following claims or the equivalents thereof.