Feuersicherheitsventil

摘要

A fire safe valve (10) which includes a body (12) having an inlet, an outlet, a valve chamber (14) communicating with the inlet and the outlet and having an opening, a bonnet (24) secured to the body and having a bore (22) therethrough with the opening of the bore communicating with the valve chamber opening and defining a back seat (30) surrounding the bore, a valve member (18), a valve stem (20) connected to the valve member and extending through the bonnet bore, a backseating shoulder (28) on the valve stem, an actuator (26), said valve stem connecting to the actuator to move the valve member within the valve chamber to open and close flow through the valve, a temperature sensitive material (34) retaining said valve stem shoulder spaced from said bonnet bore seat during normal operations and allowing additional movement of the valve stem responsive to excessive temperatures to bring the valve stem shoulder into engagement with the bonnet bores seat to backseat and prevent flow of fluids within the valve from escaping therefrom. A heat transmitting jacket (44) is connected between a position close to said heat sensitive means and a position spaced therefrom to ensure the early transmission of heat to the temperature sensitive material when remote portions of the valve are subjected to fire. The jacket includes heat pipes (52) mounted in spaced ring for the transmission of heat.