SUBSURFACE SAFETY VALVE OF MINIMIZED LENGTH

摘要

A subsurface safety valve 10 of minimized length comprises a tubular val ve housing 12 with a valve closure member 18 therein movable between an open an d a closed position, an axially shiftable flow tube 24 for opening the valve closure member 18, a plurality of longitudinally disposed springs 38 radially spaced about the housing 12 for biasing the flow tube 24 to a closed position, and a piston a nd cylinder assembly 26 to move the flow tube 24 to an open position, with a portion of the assembly 26 longitudinally overlapping at least one of the springs 38. The safety valve includes simple mechanisms to lock out the safety valve, and to establish secondary hydraulic communication with a wireline set secondary valve set within the locked out safety valve.