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CN-224229760-U - High-cleanliness gas circuit control structure

CN224229760UCN 224229760 UCN224229760 UCN 224229760UCN-224229760-U

Abstract

The utility model relates to a high-cleanliness gas circuit control structure. The utility model comprises a filtering pressure reducing valve, a double-acting positioner, a first speed increaser, a second speed increaser, a pressure reducing valve, a one-way valve and a pneumatic actuator, wherein the output end of the filtering pressure reducing valve is connected with an air inlet of the double-acting positioner, the pneumatic actuator is used for controlling the opening or closing of the valve and comprises a piston cavity and a piston movably connected in the piston cavity, the piston divides the piston cavity into a first cavity and a second cavity, two control output ports of the double-acting positioner are respectively connected to the air inlets of the first speed increaser and the second speed increaser, the air output end of the first speed increaser is connected to the first cavity, the air output end of the second speed increaser is connected to the second cavity through the pressure reducing valve, and the one-way valve is connected in parallel to the pressure reducing valve. The utility model can effectively ensure the cleanness of the inside of the actuator, prolong the service life of the actuator and ensure the reliable and stable quality of the sealing surface of the valve.

Inventors

  • QIAN MINGFENG
  • WU RINA
  • QI HAIJUN
  • BIAN HONGFEI

Assignees

  • 无锡宝牛阀业有限公司

Dates

Publication Date
20260512
Application Date
20250521

Claims (5)

  1. 1. The high-cleanliness gas circuit control structure is characterized by comprising a filtering pressure reducing valve (10), a double-acting positioner (20), a first speed increaser (30), a second speed increaser (40), a pressure reducing valve (50), a one-way valve (60) and a pneumatic actuator (70); Wherein the output end of the filtering and pressure reducing valve (10) is connected with the air inlet of the double-acting positioner (20); the pneumatic actuator (70) is used for controlling the opening or closing of the valve (80) and comprises a piston cavity (701) and a piston (702) movably connected in the piston cavity (701), and the piston (702) divides the piston cavity (701) into a first cavity (701 a) and a second cavity (701 b); The double-acting positioner (20) can adjust the gas output quantity of the first speed increaser (30) and the second speed increaser (40) according to an input control signal; the gas output end of the first speed increaser (30) is connected to the first cavity (701 a); The gas output end of the second speed increaser (40) is connected to the second cavity (701 b) through the pressure reducing valve (50), and the one-way valve (60) is connected to the pressure reducing valve (50) in parallel.
  2. 2. The high-cleanliness gas circuit control structure according to claim 1, wherein the input control signal is a 4-20 ma direct current electric signal or an FF field bus signal.
  3. 3. The high-cleanliness gas path control structure according to claim 1, wherein the first speed increaser (30) and the second speed increaser (40) are respectively used for controlling opening and closing actions of a valve (80) of the pneumatic actuator (70), wherein the first speed increaser (30) controls a piston (702) to move towards an opening direction of the valve (80), and the second speed increaser (40) controls the piston (702) to move towards a closing direction of the valve (80).
  4. 4. A high cleanliness gas path control structure according to claim 3, characterized in that the pressure reducing valve (50) is capable of controlling the pressure entering the second chamber (701 b) to be 0.1MPa or less.
  5. 5. The high-cleanliness air path control structure according to claim 1, wherein the pneumatic actuator (70) further comprises a crank (708), a spring chamber (703) and a spring (704) arranged in the spring chamber (703), the piston (702) is connected with a driving rod (705), the driving rod (705) is connected with a sliding block (706), the driving rod (705) is connected with the spring (704), the crank (708) is provided with a sliding groove (707) for the sliding block (706) to slide, and the crank (708) is connected to a driving shaft of a valve (80).

Description

High-cleanliness gas circuit control structure Technical Field The utility model relates to the technical field of valves, in particular to a high-cleanliness gas circuit control structure. Background With the continuous investment and construction of important industries such as petroleum and natural gas, petrochemical industry, environmental protection, electric power, metallurgy and the like, higher requirements are put forward on the performance stability, reliability and capability of adapting to complex environments of various automatic control equipment. In process control systems, pneumatic control valves are widely used for automatic adjustment of fluid parameters, and the actuator portion thereof is usually driven by compressed air to complete the opening and closing operations, which is an important end-effector for achieving closed-loop control. In the prior art, a conventional pneumatic actuator control structure generally adopts a single-acting positioner to match with single-side air source control, and is shown with reference to fig. 3, and mainly comprises a filtering pressure reducing valve 1, a single-acting positioner 2, a speed increaser 3 and an actuator 4. By way of example, the controller outputs a gas signal to open the valve when the control signal is raised, and shuts off the gas source when the signal is lowered or fails, and the actuator returns to close the valve by the elastic force of the internal spring. In this process, the cavity on one side of the actuator needs to be communicated with the outside through the exhaust port to suck in the outside air to complete the volume compensation. However, in high cleanliness requirements or in harsh industrial field environments, such as working conditions of high dust, corrosive gas, humid media, etc., the external air suction path inevitably introduces pollutants, which results in problems of abrasion, sealing failure, delayed response, etc. inside the actuator, thereby reducing the operational reliability of the system and the service life of the actuator. Meanwhile, the traditional structure lacks accurate regulation and control on the air supply pressure of the actuator, and excessive compaction possibly occurs when the valve is closed, so that the service life of the sealing pair is influenced, and the sealing stability is reduced. Disclosure of Invention Therefore, the high-cleanliness gas circuit control structure provided by the utility model can effectively ensure the inside of the actuator to be clean when the external environment is severe, prolong the service life of the actuator and ensure the reliable and stable quality of the sealing surface of the valve. In order to solve the technical problems, the utility model provides a high-cleanliness gas circuit control structure, which comprises a filtering pressure reducing valve, a double-acting positioner, a first speed increaser, a second speed increaser, a pressure reducing valve, a one-way valve and a pneumatic actuator; the output end of the filtering pressure reducing valve is connected with the air inlet of the double-acting positioner; The pneumatic actuator is used for controlling the opening or closing of the valve and comprises a piston cavity and a piston movably connected in the piston cavity, and the piston divides the piston cavity into a first cavity and a second cavity; The two control output ports of the double-acting positioner are respectively connected to respective air inlets of the first speed increaser and the second speed increaser; the double-acting positioner can adjust the gas output of the first speed increaser and the second speed increaser according to an input control signal; the gas output end of the first accelerator is connected to the first cavity; the gas output end of the second speed increaser is connected to the second cavity through the pressure reducing valve, and the one-way valve is connected to the pressure reducing valve in parallel. In one embodiment of the present utility model, the input control signal is a 4-20 ma dc electrical signal or an FF fieldbus signal. In one embodiment of the present utility model, the first speed increaser and the second speed increaser are respectively used for controlling the opening and closing actions of the valve of the pneumatic actuator, wherein the first speed increaser controls the piston to move towards the opening direction of the valve, and the second speed increaser controls the piston to move towards the closing direction of the valve. In one embodiment of the present utility model, the pressure reducing valve is capable of controlling the pressure entering the second chamber to be 0.1MPa or less. In one embodiment of the utility model, the pneumatic actuator further comprises a crank, a spring cavity and a spring arranged in the spring cavity, wherein the piston is connected with a driving rod, the driving rod is connected with a sliding block, the driving rod is connected with the s