Hydraulic circuit for controlling a movable component
AssigneeNational Oilwell Varco, L.P.
InventorsRichard W. Cowan, Frank Benjamin Springett, James William Weir, Travis James Miller, James Landrith
Life of this patent
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Abstract
Hydraulic circuits for controlling a movable component use one or more of a plurality of fluid supplies. Pressurized fluid flowing from one supply is routed toward the component and is not inadvertently vented into another fluid supply, or into an exit port. A backflow path is provided for fluid returning from the hydraulic component when the component is actuated in a reversed direction. The hydraulic circuits can be used, for example, on blowout preventers in a subsea environment.
Claims17
1-15. (canceled)
A hydraulic circuit for controlling a movable component using one or more of a plurality of fluid supplies, comprising:
- a plurality of check valves, each one of the plurality of check valves fluidly coupled to a corresponding one of the plurality of fluid supplies and oriented to prevent fluid backflow toward the corresponding fluid supply;
- a first flowline in fluid communication between the plurality of fluid supplies downstream of the corresponding one of the plurality of check valves;
- a function port fluidly coupled to the movable component;
- a venting port;
- a valve fluidly coupled between the function port and the venting port, the valve having a first position wherein the valve prevents flow between the function port and the venting port, and a second position wherein the valve allows flow between the function port and the venting port;
- a pressure path between at least one of the plurality of fluid supplies and the valve;
- and
- a second flowline fluidly coupling the valve and the first flowline,
- wherein the valve is normally in the second position upon removing pressure in the pressure path, and
- wherein the valve is shifted to the first position upon supplying pressure in the pressure path.
A method of controlling a movable component using one or more of a plurality of fluid supplies, comprising:
- fluidly coupling a function port to the movable component;
- fluidly coupling a valve between the function port and a venting port, the valve having a first position wherein the valve prevents flow between the function port and the venting port, and a second position wherein the valve allows flow between the function port and the venting port;
- providing a pressure path between at least one of the plurality of fluid supplies and the valve,
- preventing fluid backflow toward any of the plurality of fluid supplies using one or more check valves;
- shifting the valve in the second position upon removing pressure in the pressure path;
- shifting the valve in the first position upon supplying pressure in the pressure path;
- and
- flowing hydraulic fluid from the at least one of the plurality of fluid supplies into the function port sequentially after the valve being shifted in the first position.
Dependencies are inferred from the claim text.