US Patent 10174589 Magnetic spring booster for subsurface safety valve

Disclosed is a subsurface safety valve with a magnetic booster feature. One disclosed safety valve includes a housing, a flow tube reciprocably disposed between an upper position and a lower position within the housing, a first magnetic element coupled to the housing, and a second magnetic element coupled to the flow tube and configured such that interaction of the first and second magnetic elements induces at least one of a first force on the flow tube when the flow tube is in the upper position and a second force on the flow tube when the flow tube is in the lower position.