Injection line valve mechanism

Abstract

A downhole valve assembly, including a line operatively arranged to carry a fluid, a splitter arranged on the line, the splitter dividing the line into a control leg and an injection leg. The injection leg terminating in an injection port, and a valve mechanism actuatable for selectively sealing the injection port, the valve mechanism controllable via a fluid pressure in the line, the fluid pressure communicated to the valve mechanism via the control leg for actuating the valve mechanism.

1 . A downhole valve assembly, comprising:
 a line operatively arranged to carry a fluid;   a splitter arranged on the line, the splitter dividing the line into a control leg and an injection leg, the injection leg terminating in an injection port; and   a valve mechanism actuatable for selectively sealing the injection port, the valve mechanism controllable via a fluid pressure in the line, the fluid pressure communicated to the valve mechanism via the control leg for actuating the valve mechanism.   
     
     
         2 . The assembly of  claim 1 , wherein the control leg terminates in a sealed chamber. 
     
     
         3 . The assembly of  claim 2 , wherein the valve mechanism includes a slidable sleeve. 
     
     
         4 . The assembly of  claim 3 , wherein the sleeve includes a profile operatively arranged in the sealed chamber to enable creation of a pressure differential across the sleeve for controlling actuation of the sleeve based on the fluid pressure in the line. 
     
     
         5 . The assembly of  claim 2 , wherein the valve mechanism includes a piston at least partially located in the sealed chamber. 
     
     
         6 . The assembly of  claim 5 , wherein the piston includes a passage therethrough, the passage alignable with oppositely disposed portions of the injection leg for selectively enabling fluid communication between the line and the injection port. 
     
     
         7 . The assembly of  claim 1 , further comprising an actuator for urging the valve mechanism into a closed position by default, wherein the fluid pressure in the line must overcome a force exerted by the actuator to transition the valve mechanism into an open position. 
     
     
         8 . The assembly of  claim 7 , wherein the actuator is a spring. 
     
     
         9 . The assembly of  claim 1 , wherein the injection port is in fluid communication with production tubing when the valve mechanism is in an open position and sealed from the production tubing when the valve mechanism is in a closed position. 
     
     
         10 . The assembly of  claim 1 , wherein the injection leg includes a check valve for preventing back flow of fluid through the line. 
     
     
         11 . The assembly of  claim 10 , wherein the injection leg includes a pressure differential device for creating a pressure differential across the check valve. 
     
     
         12 . The assembly of  claim 11 , wherein a first pressure is required to open the valve mechanism, a second pressure is required to overcome the pressure differential device, and the second pressure is greater than or equal to the first pressure. 
     
     
         13 . A method of injecting fluid downhole, comprising:
 pumping a fluid in a line, the line including a splitter for dividing the line into a control leg and an injection leg, the injection leg terminating in an injection port; and   selectively controlling a valve mechanism to open and close the injection port based on the fluid pressure of the fluid in the line, the fluid pressure communicatable to the valve mechanism via the control leg.   
     
     
         14 . The method of  claim 13  wherein the valve mechanism includes a slidable sleeve. 
     
     
         15 . The method of  claim 13 , wherein the sleeve includes a profile in fluid communication with the line for enabling creation of a pressure differential across the sleeve for actuating the sleeve based on the fluid pressure in the line. 
     
     
         16 . The method of  claim 13 , wherein selectively controlling the valve mechanism further comprises increasing the fluid pressure to equal or exceed a first threshold pressure for opening the injection port. 
     
     
         17 . The method of  claim 16 , further comprising automatically returning the valve mechanism to a closed positioned when the fluid pressure falls below the first threshold pressure. 
     
     
         18 . The method of  claim 17 , wherein a spring biases the valve mechanism to automatically return to the closed position. 
     
     
         19 . The method of  claim 16 , further comprising increasing the fluid pressure in the line to a second threshold pressure, the second threshold pressure greater than the first threshold pressure and required to open a check valve included along the injection leg upstream of the injection port. 
     
     
         20 . The method of  claim 13 , wherein the valve mechanism includes a piston.