Multi-piston pump having multiple inlet conduits

Abstract

A pump includes multiple piston chambers each including a piston, an inlet valve and an outlet valve. The pump further includes a first input conduit coupled to the inlet valve of each of a first subset of the piston chambers, a second input conduit coupled to the inlet valve of each of a second subset of the piston chambers, and one or more output conduit coupled to the outlet valve of each of the piston chambers. A mixed fluid stream may be formed by supplying a first fluid to the first subset of piston chambers, supplying a second fluid to a second subset of piston chambers, operating the pump to discharge the first fluid through the first subset of piston chambers and discharge the second fluid through the second subset of piston chambers, and combining the first fluid discharge and the second fluid discharge to form the mixed fluid stream.

What is claimed is: 
     
         1 . A system, comprising:
 a pump including multiple piston chambers, each piston chamber including a piston, an inlet valve and an outlet valve;   a first input conduit in fluid communication with the inlet valve of each of a first subset of the piston chambers;   a second input conduit in fluid communication with the inlet valve of each of a second subset of the piston chambers; and   one or more output conduit in fluid communication with the outlet valve of each of the piston chambers.   
     
     
         2 . The system of  claim 1 , wherein the multiple piston chambers range from  2  to  5  piston chambers. 
     
     
         3 . The system of  claim 1 , characterized in that a ratio of an amount of fluid pumped from the first input conduit to an amount of fluid pumped from the second input conduit is predetermined by a first number of the piston chambers in the first subset and a second number of piston chambers in the second subset. 
     
     
         4 . The system of  claim 1 , wherein the one or more output conduit is a single output manifold that is in fluid communication with the outlet valve of each of the piston chambers in the pump body. 
     
     
         5 . The system of  claim 4 , wherein a fluid output from the multiple piston chambers into the single output manifold includes a mixture of a first fluid from the first input conduit and a second fluid from the second input conduit, wherein the mixture is characterized by a predetermined ratio of an amount of the first fluid to an amount of the second fluid that is established by a ratio of a first number of the piston chambers in the first subset and a second number of piston chambers in the second subset. 
     
     
         6 . The system of  claim 1 , wherein the one or more output conduit includes a first output conduit and a second output conduit, wherein the first output conduit is in fluid communication with the outlet valve of each of the first subset of the piston chambers, and wherein the second output conduit is in fluid communication with the outlet valve of each of the second subset of the piston chambers. 
     
     
         7 . The system of  claim 6 , further comprising:
 an inline mixer in fluid communication with the first output conduit and the second output conduit for receiving and mixing a first fluid from the first output conduit and a second fluid from the second output conduit.   
     
     
         8 . The system of  claim 7 , further comprising:
 a source of a first fluid connected to the first input conduit to supply the first fluid to the inlet valve of each of the first subset of the piston chambers; and   a source of a second fluid connected to the second input conduit to supply the second fluid to the inlet valve of each of the second subset of the piston chambers, wherein the first fluid includes an epoxy resin and the second fluid includes a hardener.   
     
     
         9 . The system of  claim 8 , further comprising:
 a coiled tubing injector for controllably extending concentric tubing into a well, wherein the first output conduit is coupled to a first channel within the concentric tubing and the second output conduit is coupled to a second channel within the concentric tubing, and wherein the inline mixer is coupled to a distal portion of the concentric tubing.   
     
     
         10 . A method of forming a mixed fluid stream, comprising:
 supplying a first fluid to a first subset of piston chambers in a pump having multiple piston chambers;   supplying a second fluid to a second subset of piston chambers in the pump having multiple piston chambers;   operating the pump to discharge the first fluid through the first subset of piston chambers and discharge the second fluid through the second subset of piston chambers; and   combining the first fluid discharged from the first subset of piston chambers with the second fluid discharged from the second subset of piston chambers to form the mixed fluid stream.   
     
     
         11 . The method of  claim 10 , wherein the first fluid is discharged from the first subset of piston chambers into a discharge manifold, the second fluid is discharge from the second subset of piston chambers into the discharge manifold, and the first and second fluids are combined within the discharge manifold. 
     
     
         12 . The method of  claim 10 , wherein the first fluid is discharged from the first subset of piston chambers into a first discharge conduit, the second fluid is discharged from the second subset of piston chambers into a second discharge conduit, and the first and second discharge conduits are connected downstream to cause mixing of the first and second fluids. 
     
     
         13 . The method of  claim 12 , wherein the first and second discharge conduits are connected to a static mixer that mixes the first and second fluids. 
     
     
         14 . The method of  claim 10 , wherein the first subset of piston chambers includes a first number of piston chambers, the second subset of piston chambers includes a second number of piston chambers, and a ratio of the first number of piston chambers and the second number of piston chambers affects relative amounts of the first fluid and the second fluid in the mixed fluid stream. 
     
     
         15 . The method of  claim 10 , wherein a ratio of a first number of piston chambers in the first subset to a second number of piston chambers in the second subset establishes a volumetric ratio of the first fluid and the second fluid in the mixed fluid stream. 
     
     
         16 . The method of  claim 15 , wherein the ratio of the first number of piston chambers in the first subset to the second number of piston chambers in the second subset is selected from 1:1, 2:1 and 3:1. 
     
     
         17 . The method of  claim 10 , wherein the first fluid includes a first reactant and the second fluid includes a second reactant that is reactive with the first reactant. 
     
     
         18 . The method of  claim 17 , wherein the first and second reactants are the components of a two-part epoxy formulation. 
     
     
         19 . The method of  claim 18 , wherein the first reactant is an epoxy resin and the second reactant is a hardener selected from an amine, imidazole, and/or anhydride. 
     
     
         20 . The method of  claim 18 , wherein none of the piston chambers in the pump ever contain both the first and second fluids.