Low-pressure pilot operated safety valve

Abstract

The invention discloses a low-pressure pilot operated safety valve. The valve comprises an execution mechanism, a transmission mechanism and a conversion mechanism, wherein the execution mechanism consists of a main valve body, a valve rod and a valve core; the transmission mechanism of a balance air chamber consists of a partition board, a cylinder, a piston and a diaphragm assembly; the conversion mechanism of a control air chamber consists of a pilot valve seat, a valve core cover, a diaphragm assembly and a pilot valve core; the pilot valve core can quickly perform air chamber sealing conversion between the pilot valve seat and the valve core cover when sensing the pressure change and moving up and down, and pressure in the control air chamber and the balance air chamber is quickly converted by switching an external drain hole; and by increasing and reducing the area of the air chambers, the main valve can be quickly opened to exhaust air and relieve pressure so as to ensure the safety, and the main valve can be accurately and stably seated and tightly closed. The valve has novel design and simple structure, the excessive pressure is only 1 to 3 percent, the opening precision is very high, the response speed is very high, the seating pressure range is a fixed value, the seating reset is accurate and reliable, and the valve has very good market prospect.

Description

Technical field: [0001] The invention relates to a valve device for safety protection of pressure vessels and pipeline equipment systems, in particular to a low-pressure pilot-operated safety valve. Background technique: [0002] We know that the so-called safety valve is an automatic valve that plays an important role in protecting pressure vessels and pipeline systems. It can automatically open and close operations by tracking the rise and fall of medium pressure in the system: During the normal operation of the system, the opening and closing parts of the safety valve are in the normally closed state. When the pressure of the medium in the pressure vessel and the pipeline system rises to or exceeds the set pressure value, it will automatically open to discharge the medium. Perform pressure relief and control the pressure not to exceed the set allowable value, so as to ensure that the equipment system will not cause safety accidents due to excessive pressure. As far as it...

AI Technical Summary

Problems solved by technology

Undoubtedly, the current pilot-operated safety valve also has some technical defects in actual use. Under the working condition of low pressure and large capacity, its response sensitivity, opening speed and sealing stability of back seat closing are often not as fast and reliable as direct acting safety valves.

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