The invention relates to a steam
safety valve, and belongs to the field of thermal power and
nuclear power valves. The steam
safety valve comprises a valve body, a
valve seat, a valve clack, a valve clack sleeve, a guide sleeve, a belleville spring, a lower spring seat, a spring, a valve rod, an upper spring seat and a spring cover and has a backpressure cavity, balance groove, steam discharging groove and strip-shaped groove structure. The valve body is in threaded connection with the
valve seat, the valve clack and the valve clack sleeve are fixed through a locking nut, and a valve clack sleeve
assembly is formed and arranged in the guide sleeve and vertically moves. A locating plate is arranged in a groove of the valve body, and compressed by the spring cover. A pin shaft is arranged on the valve rod and embedded into a strip-shaped groove of the valve clack sleeve
assembly. Compared with the prior art, according to the technical scheme, the steam
safety valve has the beneficial effects that the locating plate is arranged, and a valve clack limiting and valve rod guide structure is simplified; a universal check block and a belleville spring buffer device are arranged on the valve rod, and the influence generated by great impacts when the valve returns to the seat is reduced; and the pin shaft is arranged on the valve rod, the valve clack can be prevented from rotating, and the performance of the valve is guaranteed.