High-temperature high-pressure pneumatic control automatic pressure relief valve

Abstract

The invention relates to a high-temperature and high-pressure air-controlled automatic pressure relief valve, which includes a main valve and a pilot valve. The main valve includes a valve body, a valve disc, a valve stem, and a valve cover. The valve body is fixedly connected with the piston in the piston cavity, and the plane area of ​​the upper end surface of the piston is larger than the plane area of ​​the lower end surface of the disc; the pilot valve adopts an air-controlled valve, which includes a pilot valve body, a pilot valve disc and a pneumatic device. The inlet of the pilot valve body is connected to the inlet of the valve body, the outlet of the pilot valve body is connected to the piston cavity on the upper plane side of the piston, the pilot valve disc is connected to the transmission shaft of the pneumatic device, and the pressure sensor is connected in series to the air source control circuit of the pneumatic device The pressure control switch, the pressure sensor is installed in the inlet passage of the valve body, and the discharge hole is formed on the pilot valve body. The opening and closing state of the pilot valve is controlled by the pressure signal of the pressure sensor through the pneumatic device, which has the advantages of accurate and stable set pressure, and the discharge pressure is equal to the set pressure. Pressure relief protection device suitable for high temperature and high pressure vessels.

Description

technical field [0001] The invention relates to the field of valves, in particular to a pressure relief valve. The invention is suitable for the pressure relief protection device of high-temperature and high-pressure vessels such as steam and nitrogen. Background technique [0002] At present, the pressure relief valves used in pipelines and containers generally adopt the pilot-operated safety valve structure, and the pilot valve is used to control the main valve. The pilot valve is a spring-type safety valve with an independent pressure relief function. When the system pressure reaches the set pressure, the pilot valve opens to release the medium in the main valve piston chamber, and the main valve spring pushes the disc to open. For example, the built-in pilot safety valve whose publication number is CN102313052A includes a main valve and a pilot valve. , the pilot valve is installed in the inner hole of the main valve limit sleeve. When the medium pressure exceeds the ...

AI Technical Summary

Problems solved by technology

Its main disadvantage is that the spring has different elastic coefficients under different temperature conditions, so there are large fluctuations in the set pressure under high temperature conditions, the accuracy of the set pressure is low, the stability is poor, and the difference between the discharge pressure and the set pressure is large. Not suitable for use in containers or piping systems that require high accuracy of set pressure

Images