System for Selective Incremental Closing of a Hydraulic Downhole Choking Valve

Abstract

Systems for operating one or more sliding sleeve valves in an incremental, step-type fashion between open and closed positions, permitting the valve or valves to be choked to progressively smaller flow areas. The systems of the present invention also permit the valve or valves to be fully closed without having to progress through incremental steps.

1 . A hydraulic metering assembly for operating a hydraulic device from a fluid source between a fully open position and a fully closed position, the hydraulic metering assembly comprising:
 an incremental piston assembly operably interconnected with the hydraulic device and operable to deliver metered amounts of fluid from the fluid source to the hydraulic device, thereby operating the hydraulic device incrementally from the fully open position toward the fully closed position; and   a bypass mechanism to selectively permit substantially unrestricted fluid flow from the fluid source to the hydraulic device to move the hydraulic device to the fully closed position.   
   
   
       2 . The hydraulic metering assembly of  claim 1  wherein the bypass mechanism comprises a check valve that will open upon application of a predetermined level of fluid pressure. 
   
   
       3 . The hydraulic metering assembly of  claim 1  wherein the incremental piston assembly comprises:
 a housing defining a piston chamber and having a fluid inlet and a fluid outlet; and   a piston member moveably disposed within the piston chamber between a retracted position and an extended position, the piston member displacing a volume of fluid from the piston chamber through the fluid outlet during movement from its retracted position to its extended position.   
   
   
       4 . The hydraulic metering assembly of  claim 3  wherein the incremental piston assembly further comprises a spring for returning the piston member from its extended position to its retracted position. 
   
   
       5 . A hydrocarbon production assembly for use in a wellbore comprising:
 a hydrocarbon production string;   a production nipple incorporated into the production string, the production nipple being operable between fully open, fully closed and partially open positions;   a hydraulic open line interconnecting a fluid source with the production nipple to flow fluid from the fluid source to the production nipple to move the production nipple toward the fully open position;   a hydraulic close line interconnecting a fluid source with the production nipple to flow fluid from the fluid source to move the production nipple toward the fully closed position;   a hydraulic metering assembly incorporated into the close line, the hydraulic metering assembly comprising:   a) an incremental piston assembly operable to deliver metered amounts of fluid from the fluid source to the production nipple, thereby operating the production nipple incrementally from the fully open position toward the fully closed position; and   b) a bypass mechanism to selectively permit substantially unrestricted fluid flow from the fluid source to the production nipple to move the production nipple to the fully closed position.   
   
   
       6 . The hydrocarbon production assembly of  claim 5  wherein the bypass mechanism comprises a check valve that permits fluid flow from the fluid source to the production nipple upon application of a fluid pressure above a predetermined level. 
   
   
       7 . The hydrocarbon production assembly of  claim 6  further comprising a check valve that permits one-way fluid flow away from the production nipple. 
   
   
       8 . The hydrocarbon production assembly of  claim 5  wherein the incremental piston assembly comprises:
 a housing defining a piston chamber and having a fluid inlet and a fluid outlet; and   a piston member moveably disposed within the piston chamber between a retracted position and an extended position, the piston member displacing a volume of fluid from the piston chamber through the fluid outlet during movement from its retracted position to its extended position.   
   
   
       9 . The hydrocarbon production assembly of  claim 8  wherein the incremental piston assembly further comprises a spring for returning the piston member from its extended position to its retracted position. 
   
   
       10 . The hydrocarbon production assembly of  claim 5  wherein the production nipple comprises a sliding sleeve valve comprising:
 an outer housing defining an axial flowbore;   a lateral fluid flow port disposed through the housing;   a sleeve member disposed within the flowbore of the housing and having a lateral opening disposed therethrough;   the sleeve member being moveable with respect to the housing so that the lateral opening of the sleeve member is selectively alignable with the flow port of the housing to provide an adjustable flow area.   
   
   
       11 . The hydrocarbon production assembly of  claim 10  wherein:
 the flowbore of the housing provides a recess; and   the sleeve member presents a radially extending flange that is disposed within the recess to define first and second fluid chambers.   
   
   
       12 . A method for controlling a sleeve valve between an open position and a closed position, the method comprising the steps of:
 associating the sleeve valve with an open side fluid source for moving the sleeve valve to its open position;   associating the sleeve valve with a closed side fluid source for moving the sleeve valve to its closed position;   incorporating a hydraulic incremental piston device between the closed side fluid source and the sleeve valve, the incremental piston device being operable to transmit fluid to the sleeve valve in discrete increments;   moving the sleeve valve to a substantially fully open position; and   actuating the incremental piston device to move the sleeve valve from the substantially fully open position to a partially open position.   
   
   
       13 . The method of  claim 12  further comprising the step of bypassing the incremental piston device to move the sleeve valve to its closed position.