System and method for reducing pressure fluctuations in an oilfield pumping system

Abstract

Presented herein is a system, method, and assembly for reducing pressure fluctuations in an oilfield pumping system. The pressure fluctuation dampening assembly includes a junction, a dampening chamber, and a supply of a compressible medium. The compressible medium is supplied so as to form an interface between the fluid and the compressible medium such that a pressure fluctuation of fluid passing through the junction is reduced.

What is claimed is: 
     
         1 . A system for reducing pressure fluctuations, comprising:
 at least one pump directing fluid through a junction having a first port, a second port, and a third port;   a chamber coupled to the third port of the junction; and   a supply of a compressible medium in fluid communication with the chamber;   wherein the supply of compressible medium provides the compressible medium to the chamber so as to form an interface between the fluid and the compressible medium such that a pressure fluctuation of fluid passing through the junction is reduced.   
     
     
         2 . The system of  claim 1 , wherein the chamber is oriented so as to trap gas. 
     
     
         3 . The system of  claim 2 , wherein the chamber is substantially vertical. 
     
     
         4 . The system of  claim 1 , wherein the interface is movable in response to the pressure fluctuation of the fluid. 
     
     
         5 . The system of  claim 1 , wherein the first port is in communication with a fluid end of a pump, and the second port is in communication with a wellbore. 
     
     
         6 . The system of  claim 1 , wherein the junction is a tee-junction. 
     
     
         7 . The system of  claim 1 , wherein a sonic choke is couple to at least one of the first port and the second port. 
     
     
         8 . The system of  claim 1 , wherein the pump is a positive displacement pump. 
     
     
         9 . The system of  claim 1 , wherein the fluid is an oilfield fluid used in an oilfield operation selected from the group consisting of hydraulic fracturing, cementing, drilling, testing, measuring, stimulating, working over, completing, and producing. 
     
     
         10 . The system of  claim 1 , wherein the junction is a portion of the at least one pump. 
     
     
         11 . The system of  claim 1 , wherein the first port and the second port are substantially aligned. 
     
     
         12 . The system of  claim 1 , wherein the first port and the second port are substantially nonaligned. 
     
     
         13 . The system of  claim 1 , wherein a pressure in the junction is at least 10,000 PSI. 
     
     
         14 . The system of  claim 1 , wherein a pressure in the junction is at least 15,000 PSI. 
     
     
         15 . A method for dampening pressure fluctuations in a fluid stream, the method comprising:
 providing a junction having a first port, a second port, and a third port;   connecting the first port to at least one pump, and the second port to a wellbore;   connecting a chamber to the third port of the junction;   directing a fluid through the junction;   supplying a compressible medium to the chamber; and   forming an interface between the fluid and the compressible medium so as to reduce a pressure fluctuation in the fluid.   
     
     
         16 . The method of  claim 15 , wherein the fluid is an oilfield fluid used in an oilfield operation selected from the group consisting of hydraulic fracturing, cementing, drilling, testing, measuring, stimulating, working over, completing, and producing. 
     
     
         17 . The method of  claim 15 , wherein the compressible medium is supplied upstream of the junction. 
     
     
         18 . A pressure fluctuation dampening assembly, comprising:
 a junction having a first port, a second port, and a third port;   a chamber coupled to the third port of the junction, and oriented so as to trap gas; and   a gas supply tank in fluid communication with the chamber so as to provide gas to the chamber;   wherein gas supplied to the chamber forms an interface between a fluid passing through the junction and the gas such that a pressure fluctuation of the fluid is reduced.   
     
     
         19 . The assembly of  claim 18 , wherein the first port and the second port are substantially aligned. 
     
     
         20 . The assembly of  claim 18 , wherein the first port and the second port are substantially nonaligned. 
     
     
         21 . The assembly of  claim 18 , wherein the junction is a tee-junction.