Bidirectional sealing blowout preventer

The invention relates to ram-type blowout preventers used in well operations, such as in the recovery of hydrocarbons, for well control including preventing a well blowout. More particularly, the present invention pertains to the construction and operation of sealing devices included in the blowout preventers, and finds particular application in the operation and testing of subsea blowout preventers and other apparatus in a blowout preventer stack. A bidirectional sealing blowout preventer including bidirectional sealing blowout preventer rams, and fluid communication systems for equalizing pressure between the backs of ram guideways in a bidirectional sealing blowout preventer and a passageway through the blowout preventer. Methods for operating a bidirectional sealing blowout preventer to seal a well around a well pipe against downhole pressure to control the well, and to seal a well around a well pipe to pressure test another blowout preventer or other apparatus in a stack.