Apparatus and system to actuate and pump well bore liquids from hydrocarbon wells

Abstract

Pump apparatus and pump systems for use with hydrocarbon wells are actuated in response to a working fluid delivered at a high pressure to pump a fluid to be pumped or production fluid. The pump advantageously employs translation motion of a piston. Some embodiments employ working fluids at two ports. Other embodiments employ working fluid at one port and a spring. Working fluid may be provided via one or more hydraulically powered piston subassemblies, which may be controlled via one or more hydraulic power supplies. A flush system may include flush pump, flush valve and may be responsive to a characteristic of a fluid in a line.

1 . A pump suitable for hydrocarbon well applications, the pump comprising:
 an elongated pump body having a first end and a second end opposite the first end, a first port at least proximate the first end and a second port at least proximate the second end, a central body portion between the first and the second ends and a pair of peripheral body portions between the central body portions and respective ones of the first and the second ends, the pump body forming a longitudinally extending pump body chamber extending between the first and the second ports, the first and the second ports providing fluid communication between the longitudinally extending pump body chamber and an exterior of the pump body, the longitudinally extending pump body chamber including a production chamber between the first and the second ends and a pair of pressure chambers between the production chamber and respective ones of the first and the second ends, the production chamber having a circumference that is larger than a circumference of either of the pressure chamber; and   a piston having an elongated piston body including a first end and a second end opposite the first end, a central piston body portion between the first and the second ends and a pair of peripheral piston body portions between the central piston body portion and respective ones of the first and the second ends, the central piston body portion having an external circumference sized to be closely received by the production chamber of the pump body and the peripheral piston body portions each having a respective external circumference sized to be closely received by respective ones of the pressure chamber of the pump body, the piston body forming a passageway extending between and through the first and the second ends, the piston body slideably received in the longitudinally extending pump chamber of the pump body such that the central piston body portion divides the production chamber of the pump body into two production chamber portions, each of the production chamber portions having a volume that varies inversely with the volume of the other one of the production chamber portions, and the peripheral piston body portions received by respective ones of the pressure chambers of the pump body such that a respective volume of each of the pressure chambers of the pump body varies inversely with the volume of the other one of the pressure chamber.   
     
     
         2 . The pump of  claim 1 , further comprising:
 a first seal, the first seal received about the circumference of the central piston body to form a seal with the production chamber portion;   a second seal, the second seal received about the circumference of one of the peripheral piston body portions to form a seal with a respective one of the pressure chambers; and   a third seal, the third seal received about the circumference of the other one of the peripheral piston body portions to form a seal with a respective one of the pressure chambers.   
     
     
         3 . The pump of  claim 2  wherein the first, the second and the third seals are urethane ring seals. 
     
     
         4 . The pump of  claim 2  wherein the first, the second and the third seals are metal ring seals and the pump body chamber is hardened. 
     
     
         5 . The pump of  claim 1  wherein the pump body includes a third and a fourth port that provide fluid communication with respective ones of the production chamber portions from the exterior of the pump body to receive and expel fluid to be pumped, and wherein each of the peripheral piston body portions includes a piston head surface positioned in respective ones of the pressure chambers to be acted on by a working fluid introduced under pressure into the pressure chambers via the first and second ports to cause selective translation of the piston in the pump body chamber in two opposed directions. 
     
     
         6 . The pump of  claim 5  wherein the piston body forms a first production fluid port that provides fluid communication between the passageway of the piston body and the third port of the pump body and a second production fluid port that provides fluid communication between the passageway of the piston body and the fourth port of the pump body, further comprising:
 a first valve received in the passageway of the piston body between the first end of the piston body and the third port of the pump body; and 
 a second valve received in the passageway of the piston body between the second end of the piston body and the fourth port of the pump body. 
 
     
     
         7 . The pump of  claim 6  wherein the piston body forms a bypass channel, further comprising:
 a flush valve received in the passageway of the piston body between the first and the second valves, the flush valve response to a much higher pressure than the first and the second valves. 
 
     
     
         8 . The pump of  claim 6  wherein the piston body forms a bypass channel, further comprising:
 a first production screen coupled to the third port of the pump body; 
 a first production valve coupled to control a fluid flow via the third port of the pump body; 
 a second production screen coupled to the fourth port of the pump body; and 
 a second production valve coupled to control a fluid flow via the fourth port of the pump body. 
 
     
     
         9 . The pump of  claim 1  wherein each of the peripheral piston body portions includes a piston head surface, the piston head surface of a first one of the peripheral piston body portions positioned in a respective first one of the pressure chambers to be acted on by a working fluid introduced under pressure into the first one of the pressure chambers via the first port to cause selective translation of the piston in the pump body chamber in a first direction, and further comprising:
 a spring positioned to act on the piston head surface of the other one of the peripheral piston body portions to cause selective translation of the piston in the pump body chamber in a second direction opposite the first direction, wherein a fluid to be pumped is received in the pump body via the second port and is expelled from the pump body via the first port. 
 
     
     
         10 . The pump of  claim 9  wherein the spring moves the piston in the second direction to a position at which the piston head surface of the first one of the peripheral piston body portions is adjacent the first outlet. 
     
     
         11 . The pump of  claim 9 , further comprising:
 a first valve received in the passageway of the piston body between the first and the second ends of the piston body; and   a check valve received in the passageway of the piston body between the first valve and the second end of the piston body, wherein the first valve and the check valve are cooperatively operable to selectively allow a fluid to be pumped to flow from the production chamber to the first pressure chamber without allowing a working fluid to flow from the first pressure chamber to the production chamber.   
     
     
         12 . The pump of  claim 9 , further comprising:
 at least one spring sub removably physically coupled to the pump body and to the spring.   
     
     
         13 . The pump of  claim 1  wherein each of the peripheral piston body portions includes a piston head surface, the piston head surface of a first one of the peripheral piston body portions positioned in a respective first one of the pressure chambers to be acted on by a working fluid introduced under pressure into the first one of the pressure chambers via the first port to cause selective translation of the piston in the pump body chamber in a first direction, and further comprising:
 a spring positioned to act on the piston head surface of the other one of the peripheral piston body portions to cause selective translation of the piston in the pump body chamber in a second direction opposite the first direction, wherein a fluid to be pumped is received in the pump body via the second port and is expelled from the pump body via a third port spaced distally from the second port with respect to the first port. 
 
     
     
         14 . The pump of  claim 13  wherein the spring moves the piston in the second direction to a home position at which the piston head surface of the first one of the peripheral piston body portions is spaced from the first outlet. 
     
     
         15 . The pump of  claim 13 , further comprising:
 a first valve that selectively controls a flow via the third port of the pump body; and   a second valve that selectively controls a flow via the second port of the pump body, wherein the first and the second valves are cooperatively operable to selectively allow a fluid to be pumped to be received via the second port and expelled via the third port without allowing the fluid to be pumped to be expelled via the second port or received via the third port.   
     
     
         16 . The pump of  claim 13 , further comprising:
 at least one spring sub removably physically coupled to the pump body and to the spring.   
     
     
         17 . A pump system suitable for hydrocarbon well applications, the pump system comprising:
 a downhole pump apparatus selectively operable to pump a production fluid in response to a pressurized working fluid via translation of a piston;   at least one hydraulically powered piston subassembly configured to alternately supply a working fluid at high pressure to actuate the downhole pump apparatus to pump a fluid to be pumped;   at least one hydraulic power supply coupled to operate the at least one piston subassembly.   
     
     
         18 . The pump system of  claim 17  wherein the downhole pump apparatus is a downhole pump apparatus according to any of  claims 1  through  16 . 
     
     
         19 . The pump system of  claim 17 , further comprising:
 a flushing pump; and   a flushing valve, the flushing pump and flushing valve configured to force a very high pressure stream of liquid through the downhole pump apparatus to flush any contaminants or any buildups out of the downhole pump apparatus.   
     
     
         20 . The pump system of  claim 19 , further comprising:
 a sensor line to monitor a flow of fluid in a fluid line; and   a controller configured to shutdown the at least one hydraulic power supply and to actuate the flushing pump to generate the very high pressure stream of liquid in response to a characteristic of the flow of fluid in the sensor line that is indicative of debris in the fluid flow.   
     
     
         21 . The pump system of  claim 20  wherein the controller is configured to cause the very high pressure stream to exist the flush value in at least one of a steady state or in bursts. 
     
     
         22 . The pump system of  claim 17  wherein the at least one hydraulically powered piston subassembly includes two hydraulically powered piston subassemblies, each of the hydraulically powered piston subassemblies coupled a respective first and second working fluid ports of the downhole pump apparatus and configured to alternately supply a working fluid at high pressure to the first the second working fluid ports. 
     
     
         23 . The pump system of  claim 22  wherein the at least one hydraulic power supply includes two hydraulic power supplies, each of the hydraulic power supplies coupled to operate a respective one of the hydraulically powered piston subassemblies.