Flapper operating system without a flow tube

摘要

A subsurface safety valve features no flow tube to operate the flapper and optionally an equalizing valve in the flapper, if used. It relies on magnetic force that is selectively created to draw the flapper to the open position. A torsion spring can close the valve when the field is removed. Optionally, the fields can be set up to pull and push the flapper open or to do either one. The optional equalizer valve can also be operated by a force field, preferably magnetic.

主权项

1. A subsurface safety valve for a subterranean location accessible from a surface, comprising:
a body having a single passage therethrough and a seat surrounding said passage, said body having end connections and said body being positioned at the subterranean location with a tubular string connected to at least one of said end connections to conduct fluids through said passage in opposed directions between the subterranean location to the surface; a flapper movably mounted without a flow tube for at least one of selective opening of said passage by moving away from said seat and closing of said passage by moving into contact with said seat as a result of an indirectly applied force; said flapper supported in said body such that the flapper weight urges said flapper away from said seat; said indirectly applied force is at least one force field; said field is magnetic; said field pushes said flapper from said seat.