Pressure sensing safety device

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. The electronic circuitry produces a signal representing the condition of the pressure being sensed, which signal may be directed to the wellhead or other pressure vessel safety system to permit appropriate remedial action to be taken if necessary.