초록 ▼

A subsurface well safety valve having two control lines which run from the well surface to first and second piston and cylinder assemblies for controlling the valve. The first of the assemblies is connected to a flow tube for operating the valve but the second assembly is disconnected from the flow

A subsurface well safety valve having two control lines which run from the well surface to first and second piston and cylinder assemblies for controlling the valve. The first of the assemblies is connected to a flow tube for operating the valve but the second assembly is disconnected from the flow tube. When a failure occurs in the primary control system, the first assembly is disconnected from the flow tube and the second piston and cylinder assembly is connected to the flow tube to operate the safety valve.

대표청구항 ▼

In a subsurface well safety valve for controlling the fluid flow through a well conduit and including a housing having a bore and a valve closure member moving between open and closed positions for controlling the fluid flow through the bore, a tubular member telescopically moving in the housing for

In a subsurface well safety valve for controlling the fluid flow through a well conduit and including a housing having a bore and a valve closure member moving between open and closed positions for controlling the fluid flow through the bore, a tubular member telescopically moving in the housing for controlling the movement of the valve closure member, the improvement in fluid actuating means for actuating the valve closure member comprising, a first piston and cylinder assembly in the housing adapted to be connected to a hydraulic control line, said first assembly connected to the tubular member, a second piston and cylinder assembly in the housing adapted to be connected to a hydraulic control line, said second assembly disconnected from the tubular member, and means for disconnecting the first assembly from the tubular member and connecting the second assembly to the tubular member. The method of operating a subsurface well safety valve for controlling the fluid flow through a well conduit in which the valve includes a housing having a bore and a valve closure member moving between open and closed positions for controlling the fluid flow through the bore, a tubular member telescopically moving in the housing for controlling the movement of the valve closure member, means biasing the tubular member to a closed position, a first piston and cylinder assembly in the housing connected to the tubular member and connected to a hydraulic control line, and a second piston and cylinder assembly in the housing disconnected from the tubular member and connected to a hydraulic control line comprising, disconnecting the first assembly from the tubular member, and connecting the second assembly to the tubular member.