Because of the harsh working environment, there are certain operational risks in the production process. Among them, electromagnetic fault is a common phenomenon in the scotch yoke pneumatic actuator. Let's learn about the fixed-point maintenance and risk prevention of electromagnetic fault of the scotch yoke pneumatic actuator.

A solenoid valve is arranged in the pneumatic signal pipeline of the pneumatic actuator to realize the safe interlocking action. The solenoid valve accepts the interlocking signal from DCS to excite or release the solenoid valve coil, change the flow path, connect or disconnect the pneumatic signal and empty the pneumatic actuator chamber. The malfunction of pneumatic actuator caused by the misoperation of solenoid valve or the burnout of coil seriously affects the stability of production. In order to prevent the operation risk of pneumatic actuator caused by the fault of solenoid valve, the solenoid valve single configuration is transformed into double configuration and DCS digital output double-point setting, forming double insurance of the control relationship between solenoid valve and door. The interlocking principle of double solenoid valves is shown in Fig. 3. The output pneumatic signal of valve positioner is connected to the input end of solenoid valve 1 and solenoid valve 2 through three-way joint, and the empty hole of solenoid valve 1 is connected to the output hole of solenoid valve 2, while the output of solenoid valve 1 is connected to the pneumatic actuator chamber. When solenoid valve 1 or solenoid valve 2 fails alone, the pneumatic signal can be connected to the pneumatic actuator without affecting it. When solenoid valve 1 and solenoid valve 2 fail at the same time, the pneumatic signal will be completely disconnected and the chamber pressure of pneumatic actuator will be emptied by solenoid valve 1 and solenoid valve 2. The probability of simultaneous failure of these two solenoid valves is much lower than that of single failure. At the same time, the digital output points of DCS should be configured on different DO cards to avoid double solenoid valves connecting to the same card and avoid the problems of double solenoid valves caused by the failure of DCS cards.
Through fixed-point overhaul and risk prevention of the scotch yoke pneumatic actuator, the failure rate and risk can be effectively reduced. The above small arrangement of the scotch yoke pneumatic actuator solenoid valve failure fixed-point overhaul and risk prevention, will you?