A safety valve having a flow tube telescopically movable in the housing for controlling the opening and closing of the valve in which the housing has a fluid chamber with a piston connected to the flow tube and a fluid passageway connected to the chamber adapted to be in communication with the fluid pressure at the well surface. SAFETY VALVES A valve element and valve seat in the passageway seals off fluid flow through the seat and holds the flow tube in the open position when pressure is applied to the fluid passageway.Needle Valves Spaced minimum leak seals may be provided to form the fluid chamber. An antiburst communication line may be provided between the chamber and the bore of the safety valve having a check valve for equalizing pressure in the chamber. A valve mechanism operable by the flow tube shuts off the flow of fluid in the passageway to the fluid chamber when the valve closure member is in the open position.

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