Variable capacity plunger pump

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 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;   wherein when the plunger is at a first position the compression chamber is at a first volume to receive fluid from the plunger at a first pressure, and when the plunger is at a second position, the compression chamber is at a smaller second volume to pressurize the fluid within the compression chamber to a higher second pressure, wherein the fluid at the second pressure is discharged from the compression chamber into the outlet.   
     
     
         2 . The pump of  claim 1  further comprising a liner disposed along at least a portion of the housing bore. 
     
     
         3 . The pump of  claim 2 , wherein the liner is removable. 
     
     
         4 . The pump of  claim 3  wherein the inlet is disposed between the proximate and middle seals. 
     
     
         5 . The pump of  claim 1  wherein the inlet has an inlet axis and the housing bore has a bore axis that is at least substantially perpendicular to the inlet axis. 
     
     
         6 . The pump of  claim 1  wherein the proximal end of the plunger is coupled to an actuator. 
     
     
         7 . The pump of  claim 1  wherein the housing assembly may be coupled to a plurality of pumps as described in  claim 1 . 
     
     
         8 . The pump of  claim 1  wherein the outlet valve assembly and the discharge valve assembly are biased towards closed positions when the plunger is stationary in the loaded position. 
     
     
         9 . The pump of  claim 1  wherein the outlet valve assembly is biased towards a closed position and the discharge valve assembly is biased towards an open position when the plunger is moved from the loaded position to the dispense position. 
     
     
         10 . The pump of  claim 1  wherein the outlet valve assembly is biased towards an open position and the discharge valve assembly is biased towards a closed position when the plunger is moved from the dispense position towards the loaded position. 
     
     
         11 . 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 having a sidewall defining a plunger bore extending therethrough, the plunger including at least one opening formed in the sidewall configured to pass fluid from the inlet into the plunger bore, the plunger configured to communicate fluid from the plunger bore and to the compression chamber;   wherein when the plunger is at a first position the compression chamber is at a first volume to receive fluid from the plunger at a first pressure, and when the plunger is at a second position, the compression chamber is at a smaller second volume to pressurize the fluid within the compression chamber to a higher second pressure, wherein the fluid at the second pressure is discharged from the compression chamber into the outlet.   
     
     
         12 . The pump of  claim 11  wherein the inlet has an inlet axis and the housing bore has a bore axis that is at least substantially perpendicular to the inlet axis. 
     
     
         13 . The pump of  claim 11  wherein the proximal end of the plunger is coupled to an actuator. 
     
     
         14 . The pump of  claim 11  wherein a portion of the housing bore accommodates a removable liner having a thickness that reduces the volume of the housing bore. 
     
     
         15 . The pump of  claim 11  wherein the housing assembly may be coupled to a plurality of pumps as described in  claim 11 . 
     
     
         16 . The pump of  claim 11  wherein the outlet valve assembly and the discharge valve assembly are biased towards closed positions when the plunger is stationary in the loaded position. 
     
     
         17 . The pump of  claim 11  wherein the outlet valve assembly is biased towards a closed position and the discharge valve assembly is biased towards an open position when the plunger is moved from the loaded position to the dispense position. 
     
     
         18 . The pump of  claim 11  wherein the outlet valve assembly is biased towards an open position and the discharge valve assembly is biased towards a closed position when the plunger is moved from the dispense position towards the loaded position. 
     
     
         19 . A method for pumping hydraulic fracturing fluid, the method comprising:
 retracting a plunger to increase a volume of a compression chamber defined within a housing bore of a pump between a distal end of the plunger and an outlet of the pump, and to provide communication between an inlet of the pump and the compression chamber in order to receive fluid in a plunger bore of the plunger, the compression chamber in axial alignment with the outlet, the plunger configured to communicate fluid from the plunger bore and to the compression chamber;   moving the plunger to reduce a volume of the compression chamber to pressurize the fluid within the compression chamber; and   dispensing the pressurized fluid from the compression chamber to the outlet.   
     
     
         20 . The method of  claim 19  further including:
 altering an output capacity of the pump by lining the housing bore with a replaceable liner. 
 
     
     
         21 . A pumping module comprising:
 a plurality of pumps arranged in a side by side configuration, each pump including:   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;   wherein when the plunger is at a first position the compression chamber is at a first volume to receive fluid from the plunger at a first pressure, and when the plunger is at a second position, the compression chamber is at a smaller second volume to pressurize the fluid within the compression chamber to a higher second pressure, wherein the fluid at the second pressure is discharged from the compression chamber to the outlet.