Abstract: A blowout preventer having a body with a bore and opposing guideways intersecting the bore, a ram in each of the guideways, a cap closing the outer end of each of the guideways, an operating stem connecting to each of said rams, extending through its cap in threaded engagement and having means for engagement by a handle, such as flats on its outer end, a pair of hydraulic motors each having a housing and a rotating shaft, means for securing said motor housings to the body surrounding said guideways, means for connecting said drive shafts with the operating stems to rotate said stems, and means supplying hydraulic fluid to said motors for selective rotation of said shafts and said stems in preselected directions.

Abstract: A safety device for sensing and monitoring pressure in oil or gas wellheads, flow lines, manifolds, pipelines, and the like, as well as other pressure vessels or apparatus requiring pressure sensing and monitoring, includes a pilot device having a transducer in operative communication with the source of pressure to be sensed or monitored; the transducer producing an electrical signal proportional to the magnitude of the pressure sensed. The pilot device further includes an electronic circuit which is adjustable to provide predetermined upper and lower values representing a range of magnitudes of pressure. The electronic circuit includes a memory circuit which permits the pilot device to indicate that an out-of-range pressure has been or is being sensed. The safety device also includes a means for visibly indicating the present value of pressure being sensed as well as out-of-range pressure conditions that may have occurred previously.