WELL SAFETY VALVE

摘要

A magnetically operated fail-safe cutoff valve of general application and particularly suitable for down hole fluid well applications is provided having a simple highly reliable valve for equalizing the pressure across the main cutoff valve while closed thereby permitting the same to be opened. All operating components can be either removably installed internally of a tubing string or as a portion of the string itself. In either case, typical wire line operations can be conducted through and past the lower end of the cutoff valve since the flow path of each of the illustrative embodiments provides an unobstructed linear flow path therethrough when the valve is open. The pressure equalizing valve includes multiple flow passages and is controlled by a shrouded annular armature operable independently of a tubular armature controlling the main cutoff valve. The two armatures may be located in either common or separate flux circuits.