Positive Displacement Pump

Abstract

A positive displacement fluid pump with increased service life is described. The positive displacement pump includes a plunger, a suction bore and a discharge bore. The plunger, the suction bore and the discharge bore form a pumping chamber. The diameter of the suction bore is greater than the diameter of the discharge bore. The difference in the diameters of the suction bore and the discharge bore allows for less fluid to be discharged through the discharge valve than what is being put into the bore through the suction valve and helps in increasing the service life of the pump. A method of operation of such a positive displacement pump is also provided.

What is claimed is: 
     
         1 . A positive displacement pump, comprising:
 a movable reciprocating plunger;   a pumping chamber, wherein a volume of the pumping chamber is varied by a movement of the movable plunger inside the pumping chamber;   a suction bore providing an inlet for a fluid into the pumping chamber; and   a discharge bore providing an outlet for the fluid out of the pumping chamber, wherein an internal diameter of the discharge bore is less than an internal diameter of the suction bore, such that the difference in the diameters of the suction bore and the discharge bore is configured to maintain a continuous flow of fluid through the outlet bore.   
     
     
         2 . The positive displacement pump of  claim 1  wherein the difference in diameters is 20 percent. 
     
     
         3 . The positive displacement pump of  claim 2  wherein the difference in diameters is 10 to 15 percent. 
     
     
         4 . The positive displacement pump of  claim 3  wherein the difference in diameters is 5 to 10 percent. 
     
     
         5 . The positive displacement pump of  claim 1 , further comprising an inlet valve provided at the suction bore for controlling the fluid flow into the pumping chamber. 
     
     
         6 . The positive displacement pump of  claim 5 , further comprising at least one outlet valve provided at the discharge bore for controlling the fluid flow out of the pumping chamber. 
     
     
         7 . The positive displacement pump of  claim 6 , wherein each of the inlet valve and the outlet valve further include a seat valve, retainer valve, and a valve spring. 
     
     
         8 . A fluid pump configured to provide a continuous fluid flow, the fluid pump comprising:
 a pumping chamber;   an inlet bore for introducing fluid in the pumping chamber; and   an outlet bore, wherein a diameter of the outlet bore is less than a diameter of the inlet bore in such a way that the fluid does not fully discharge from the pumping chamber in a single pump cycle.   
     
     
         9 . The pump according to any of the above claims used in the oil and gas industry for pumping drilling fluids. 
     
     
         10 . The pump according to any of the above claims wherein the suction and discharge bore have sharp edges. 
     
     
         11 . The pump according to  claim 10  wherein the suction and discharge bore have curved edges. 
     
     
         9 . The pump according to  claim 1  used in the oil and gas industry for pumping drilling fluids. 
     
     
         12 . The pump according to  claim 8  used in the oil and gas industry for pumping drilling fluids.