Diaphragm Control Valve

Abstract

The invention discloses a diaphragm type control valve. The diaphragm type control valve is mainly composed of a control valve body, a valve barrel, an upper valve cover, an adjusting screw rod, a pressure adjusting spring, a pressure adjusting shaft and a light elastic diaphragm assembled between the control valve body and the valve barrel, wherein the elastic diaphragm with the light property is used for replacing a heavy piston and is used as an online overpressure induction element of the control valve; the sensitivity property on pipeline pressure changes by the elastic diaphragm is sufficiently utilized so that the overpressure induction sensitivity and the conduction reaction speed of the control valve are improved. A trial shows that the rapid reaction control capability on overpressure switching-off of a main valve can be obviously enhanced; the technical requirements on overpressure switching-off opening and closing precision by a fuel gas transportation and conveying operating instruction can be perfectly met even under a low-pressure gas medium working condition. The diaphragm type control valve has the prominent advantages of simple structure, low manufacturing cost, high overpressure induction sensitivity, rapid conduction reaction speed and strong capability of controlling overpressure switching-off of the main valve, and has a good popularization and application prospect in a petrochemical gas transportation industry.

Description

technical field [0001] The invention relates to an overpressure closing security control device for a gas safety cut-off valve, in particular a diaphragm control valve, which is especially suitable for matching with the current gas safety cut-off valve, and can be quickly closed when the pipe network is overpressured. The shut-off valve is used for safety protection, and has extremely high opening and closing precision and safety protection performance. Background technique [0002] The applicant once proposed a utility model patent technology named "a gas safety cut-off valve" (patent number: ZL200920079933.9) on March 31, 2009, which includes a main valve installed on the gas pipeline and The piston controller is connected to the main valve to control the air chamber by the pressure guide tube. The piston controller is composed of the valve body, the middle valve box installed on the valve body, the upper valve cover, the intake valve, the discharge valve and The piston v...

AI Technical Summary

Problems solved by technology

However, we also found in the follow-up research and development and market research of this product that the piston controller of the current "gas safety shut-off valve" still has technical defects such as slow overpressure response speed and low opening and closing precision in actual operation. The reason is: its piston controller uses the "piston valve rod together with the valve core" as an overpressure sensing moving element. Because the "piston" is heavy and heavy, its "static inertia" is large, which leads to One of the main reasons for the current "gas safety shut-off valve" is "slow response speed and low opening and closing precision", especially when the piston body made of metal material is used as the sensing element under low-pressure gas-mediated working conditions, it has a great impact on the opening and closing. The effect of closed control accuracy is more obvious

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