Solution for regulating type quick-cutting pneumatic actuator
25-05-09
The pneumatic fork-type actuator, as a major component of control valves, features high reliability, large output torque, simple maintenance and repair, strong adaptability to the environment, and explosion-proof function. It is widely used in various production processes of industries such as petroleum, chemical engineering, power, metallurgy, textile, national defense, and water treatment. According to the different process requirements of the control valve, pneumatic actuators of different specifications can be selected, which play a crucial role. Large-diameter, high-pound class, metal-sealed and other control valves require a relatively large driving torque, and the cylinder bore (volume) of the required actuator is also relatively large. Therefore, under a certain air source pressure, large-sized pneumatic actuators have slow inflation and deflation speeds and long response times, which cannot meet the reliability, speed and accuracy requirements of valve control. It seriously affects the corresponding indicators of the control valve and fails to meet the requirements of the process production.
Wuxi Fostoop Technology Co., Ltd. has optimized the control loop in response to the problems raised above. For example, for the fork-type pneumatic actuator of HPY-B2-401-SRC4 (spring return approximately 4000Nm@4Bar Air supply), it is necessary to achieve an adjustment stroke time of less than 5 seconds and an emergency quick closing time of less than 0.5 seconds. The adopted solution is to install a gas source amplifier and a speed increaser relay at the air inlet of the actuator. The speed increaser relay receives the pressure signal at the outlet of the positioner in the air path leading to the actuator and provides the amplified gas source flow to supply gas to the actuator through the gas source amplifier. This circuit can increase the action speed of the actuator. It can safely and reliably achieve precise control, accurate positioning, rapid response, prompt action, and realize functions such as emergency cut-off.
The working principle of this pneumatic actuator is: As shown in Figure 1, when solenoid valve 3 is energized, the gas source amplifier reverses (the positioner side is connected to the air inlet of the actuator, and the other gas source amplifier is closed). Meanwhile, the 4-20mA electrical signal provided by the DCS is converted into a gas signal by the positioner, and then this gas signal is used to control the speed increaser, so that the gas flow rate is amplified proportionally according to the gas signal. Then it enters the air inlet of the actuator through the air source amplifier, thereby achieving the effect of increasing the speed and meeting the opening requirements of the valve. The actual opening time is 3.5 seconds. When power and signal are lost, the positioner and the speed increaser relay stop working. The single electrically controlled solenoid valve returns to its original position by a spring, putting the two air source amplifiers in the exhaust state, which meets the function of rapid exhaust of the single-acting pneumatic actuator. The actual closing time is less than 0.5 seconds.
The characteristics of the pneumatic actuator adopting this circuit are as follows: it can achieve rapid air charging and discharging of the pneumatic actuator, shorten the full-stroke control time of the control valve, and at the same time meet the rapid cut-off function in emergency situations, ensuring the stability, accuracy, rapidity and reliability of the actuator.
关键字：
福斯拓科,调节型快速切断气动执行器解决方案
Previous：
Wuxi Force & Torque Technology Co,Ltd
Add: No.8 Dongyue Road, Xishan District, Wuxi, China
Fax: +86-510-88550590/91/92-8020
Wuxi Force & Torque Technology Co,Ltd
Add: No.8 Dongyue Road, Xishan District, Wuxi, China
Tel: +86-510-88550590/91/92
Fax: +86-510-88550590/91/92-8020
Email: sales@force-torque.cn
Website: www.force-torque.cn