Pump discharge valve assembly

Abstract

A plunger pump includes a housing with a discharge valve in communication with an outlet. The housing includes a bore that slidably accommodates a plunger. The housing also includes an inlet. The plunger has a closed proximal end connected to an actuator and a distal end with an outlet valve. The plunger also includes a sidewall with an opening that is in communication with the inlet of the housing. Fluid flows through the inlet and through the opening and into the plunger. When the plunger is retracted away from the discharge valve, the outlet valve of the plunger opens thereby providing fluid for the housing bore. As the plunger is moved towards the discharge valve, pressure in the housing bore increases thereby opening the discharge valve and permitting the pressurized fluid to exit through the outlet.

1 . A discharge valve assembly for a pump, comprising:
 a discharge valve sleeve coupled to a bore of a pump, the discharge valve sleeve including a radially inwardly directed valve seat at a proximal end of the discharge valve sleeve;   a retainer including a proximal side spaced apart from the valve seat and a distal side to face an outlet of the pump, the retainer having a hub extending proximally from the proximal side of the retainer, the retainer including at least one passageway axially extending therethrough to provide communication between the proximal side of the retainer and the outlet of the pump;   a discharge valve head disposed between the retainer and the discharge valve seat, the discharge valve head having a proximal side to sealably engage the valve seat when the discharge valve assembly is in a closed position, and a shaft extending from a distal side of the discharge valve head slidably received in the hub of the retainer;   wherein the discharge valve head is biased in its closed position.   
     
     
         2 . The discharge valve assembly of  claim 1  wherein the hub includes a radially extending orifice for providing fluid communication between an annular cavity defined between the retainer and the valve seat and a space defined within the hub between a distal end of the shaft and the proximal side of the retainer. 
     
     
         3 . The discharge valve assembly of  claim 1  wherein the proximal side of the discharge valve head is frusto-conically shaped and a distal side of the valve seat is frusto-conically shaped. 
     
     
         4 . The discharge valve assembly of  claim 1  wherein a biasing element is contained within the hub between a distal end of the shaft and the proximal side of the retainer. 
     
     
         5 . The discharge valve assembly of  claim 4  wherein the hub includes at least one radial opening providing communication between a space occupied by the biasing element between the distal end of the shaft in the proximal side of the retainer. 
     
     
         6 . This discharge valve assembly of  claim 1  wherein the retainer has a disk body having a threadable portion formed along a perimeter of the disk body for threadable engagement with to a distal end of an inner wall of the discharge valve sleeve. 
     
     
         7 . The discharge valve assembly of  claim 1  wherein the sleeve is threadably connected to a distal end of the housing assembly. 
     
     
         8 . A pump comprising:
 an inlet to receive fluid;   an outlet to discharge fluid;   a housing assembly defining a housing bore;   an axial plunger slidably disposed within the housing bore to form a compression chamber disposed between a distal end of the plunger and the outlet, the compression chamber in axial alignment with the outlet, the plunger configured to receive fluid from the inlet and pass fluid to the compression chamber;   a discharge valve sleeve coupled to the housing bore, the discharge valve sleeve including a valve seat at a proximal end;   a retainer including a proximal side spaced apart from the valve seat and a distal side to face the outlet, the retainer having a hub extending proximally from the proximal side of the retainer, the retainer including at least one passageway extending therethrough to provide communication between the proximal side of the retainer and the outlet;   a discharge valve head disposed between the retainer and the discharge valve seat, the discharge valve head having a proximal side to sealably engage the valve seat when the discharge valve assembly is in a closed position, and a shaft extending from a distal side of the discharge valve head slidably received within the hub of the retainer, wherein the discharge valve head is biased in a closed position,   wherein when the pressure of the fluid within the compression chamber is beyond a threshold pressure, the discharge valve head is movable away from the closed position to permit pressurized fluid to move from the compression chamber to the outlet.   
     
     
         9 . The pump of  claim 8  wherein the hub includes a radial orifice for providing fluid communication between a space in the hub between a distal end of the shaft and the proximal side of the retainer. 
     
     
         10 . The pump of  claim 8  wherein the proximal side of the discharge valve head is frusto-conically shaped and a distal side of the valve seat is frusto-conically shaped. 
     
     
         11 . The pump of  claim 8  wherein a biasing element is trapped in the hub between a distal end of the shaft and the proximal side of the retainer. 
     
     
         12 . The pump of  claim 8  wherein a spring biases the discharge valve head towards the discharge valve seat. 
     
     
         13 . This pump of  claim 8  wherein the retainer is threadably connected to the distal end of the discharge valve sleeve. 
     
     
         14 . The pump of  claim 8  wherein the discharge valve sleeve is threadably connected to a distal end of the housing assembly. 
     
     
         15 . A method for pumping hydraulic fracturing fluid, the method comprising:
 biasing a discharge valve head against a discharge valve seat to close an outlet of a pump, the discharge valve head being connected to a shaft that is slidably received within a hub connected to a proximal side of a retainer;   providing communication between an inlet of the pump and an axial housing bore defined by a housing assembly of the pump;   moving a plunger disposed axially within the housing bore towards the discharge valve head thereby pressurizing a portion of the housing bore disposed between the plunger and the discharge valve head to form a compression chamber in axial alignment with the discharge valve head thereby overcoming the bias of the discharge valve head against the valve seat and providing communication between the compression chamber and the outlet of the pump; and   dispensing fluid through the outlet.   
     
     
         16 . The method of  claim 15  further including:
 isolating an inlet of the pump from the housing bore thereby depressurizing the compression chamber; 
 biasing the discharge valve head towards the discharge valve seat; and 
 dampening engagement between the discharge valve head and the discharge valve seat by providing communication between a space defined by the distal end of the shaft, the hub and the proximal side of the retainer. 
 
     
     
         17 . The method of  claim 15  wherein the hub has a radial orifice for the release of pressurized fluid for dampening the engagement between the discharge valve head and the discharge valve seat. 
     
     
         18 . The method of  claim 15  wherein the providing of communication between the inlet and the housing bore further includes communicating fluid from the inlet, through an opening in the plunger, through the plunger and out through and outlet valve assembly disposed at a distal end of the plunger. 
     
     
         19 . The method of  claim 15  wherein the outlet is detachably coupled to the housing assembly, the retainer is detachably coupled to a discharge valve sleeve and the discharge valve sleeve is detachable coupled to the housing assembly, the method further including replacing the discharge valve seat and the discharge valve head as follows:
 removing the outlet from the housing assembly; 
 removing the retainer from the discharge valve sleeve; 
 removing the discharge valve sleeve and discharge valve head from the housing assembly; 
 providing a new or repaired discharge valve sleeve and a new or repaired discharge valve head; 
 coupling the new or repaired discharge valve sleeve to the housing assembly; 
 inserting the new or repaired discharge valve head into the discharge valve sleeve; 
 coupling the retainer to the discharge valve sleeve and the hub over the shaft of the discharge valve head; 
 re-coupling the outlet to the housing assembly. 
 
     
     
         20 . The method of  claim 15  wherein the retainer is threadably connected to the discharge valve sleeve and the discharge valve sleeve is threadably connected to the housing assembly.