Steam safety valve

Abstract

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.

Description

technical field [0001] The invention relates to a steam safety valve, which belongs to the field of thermal power and nuclear power valves. Background technique [0002] Safety valves are installed on thermal power, nuclear power units and pressure vessels, and are important equipment to protect the safety of units and containers. [0003] The steam safety valve in the prior art mainly adopts a stroke control ring on the valve stem. After the valve is opened, the stroke control ring touches the cooler upwards to control the valve stroke; The independent exhaust chamber and adjusting sleeve are used to adjust the pressure of the back cavity of the valve disc. There are many parts and the valve structure is complex. [0004] In the existing technology, as described in the utility model patent CN201020150195.5, an independent back pressure adjustment mechanism is installed on a main steam safety valve to adjust the back pressure of the disc. There are many parts and complex st...

AI Technical Summary

Problems solved by technology

[0003] The steam safety valve in the prior art mainly adopts a stroke control ring on the valve stem. After the valve is opened, the stroke control ring touches the cooler upwards to control the valve stroke; Independent exhaust chamber and adjusting sleeve to adjust the disc back chamber pressure, many parts and complicated valve structure

[0004] The existing technology is as described in the utility model patent CN201020150195.5. An independent back pressure adjustment mechanism is installed on a main steam safety valve to adjust the back pressure of the disc. There are many parts and complex structures, and the valve has a high center of gravity and poor shock resistance.

In addition, the outer circle of the disc sleeve does not have multiple balance grooves in the horizontal circumferential direction, and the disc is prone to deflection during opening and reseating, which affects the sealing performance of the valve.

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