Pneumatic film regulating valve actuator diaphragm protection gas source circuit

Abstract

The invention discloses a membrane-protecting air source loop for a pneumatic diaphragm regulating valve executing mechanism. The membrane-protecting air source loop comprises at least one air supplying air channel. One ends of inlet ball valves inside the air supplying air channels are used for being connected with a pressure air source, and the other ends of the inlet ball valves inside the airsupplying air channels are connected with air inlet working openings of pneumatic control two-position two-way reversing valves and air inlet working openings of pneumatic control two-position three-way reversing valves. Air outlet working openings of the pneumatic control two-position two-way reversing valves are connected with inlets of first one-way valves and control openings of the pneumaticcontrol two-position three-way reversing valves, and outlets of the first one-way valves are connected with control openings of the pneumatic control two-position two-way reversing valves. Air outletworking openings of the pneumatic control two-position three-way reversing valves are connected with inlets of pressure reducing valves, outlets of the pressure reducing valves are connected with oneends of outlet ball valves, and the other ends of the outlet ball valves are used for being connected with the pneumatic diaphragm regulating valve executing mechanism. The air inlet ends of safety valves are connected with outlets of the pressure reducing valves, and outlets of the safety valves are connected with the control openings of the pneumatic control two-position two-way reversing valves. According to the membrane-protecting air source loop, a membrane can be protected against high air pressure damage, and overhauling is convenient.

Description

technical field [0001] The invention belongs to the technical field of pneumatic control, and in particular relates to a diaphragm protection gas source circuit for an actuator of a pneumatic film regulating valve. Background technique [0002] Pneumatic film control valves are widely used in the field of industrial production, and their basic structure is as follows: figure 1 As shown, it is divided into an actuator 1' and a regulating valve 2', wherein the actuator includes a diaphragm 10', a spring 11' and a valve stem 12'. [0003] For the pneumatic film regulating valve, under normal use conditions, the diaphragm of the regulating valve has a long service life and is not easy to be damaged. However, if the pressure of the air source of the regulating valve exceeds the upper limit of the operating pressure of the actuator, the service life of the diaphragm of the actuator will be reduced. When the pressure of the air source exceeds the upper limit of the operating press...

AI Technical Summary

Problems solved by technology

[0007] (1) When the air source pressure reducing valve fails or due to the drift of the outlet pressure, high air pressure will be generated, which will reduce the service life of the diaphragm of the actuator of the pneumatic film regulating valve. Internal damage, which affects the production of the process flow;

[0008] (2) When the air source circuit part fails, such as air leakage of the components on the pipeline and the failure of the pressure reducing valve, there is no way to perform online maintenance without stopping the normal operation of the pneumatic film regulating valve, and the system reliability is poor;

[0009] (3) There is no automatic protection of high air source pressure and high pressure alarm indication, making it difficult for production personnel to find abnormal pressure

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