Analyze the inspection methods of pneumatic actuators
At present, the application of pneumatic valves in various industries is becoming more and more extensive, and the technology of pneumatic actuators is getting better and better. The gap between domestic pneumatic actuators and imported pneumatic actuators is getting smaller and smaller, and the types are getting richer and richer.
The following section will introduce several inspection methods of pneumatic actuators for you:
1. Fix the pneumatic actuator on the calibration table and connect the air source respectively. Control air source and displacement detection connecting rod; Accurately adjust the instrument on the calibration table;
2. Mechanical zero calibration: input 4.MA current signal (0%).02mpa, at this time, the cylinder piston stroke should be zero; If it is not zero, the zero can be adjusted by adjusting the nut on the zero adjustment screw (tighten the nut when the zero is high); The zero point and measuring range need to be adjusted repeatedly; Zero error ≤1%;
3. Mechanical full-scale calibration: input 20mA current signal (100%).10mpa, at this time, the cylinder piston stroke should be the upper limit; If it is not the upper limit, the range can be adjusted by adjusting the tightness of the range spring (when the range is small, when the range is large); The zero point and range need to be adjusted repeatedly; Full range error ≤1%;
4. Mechanical range midpoint positioning: zero and range adjustment, input 12mA current signal (50%).06mpa), adjust the position of the transmitter link, so that it remains perpendicular to the horizontal plane at this point;
5. Full stroke deviation calibration: Input control gas signal 0.02mpa (0%).036mpa (20%).0.052mpa (20%).0.068mpa (60%).0.084mpa (80%).0.1mpa (100%), so that the cylinder piston to go a complete stroke, each point deviation should be less than 1.5%;
6. Nonlinear deviation test: input control gas signal 0.02mpa (0%).10mpa (100%).02mpa (0%), the actuator to complete the stroke, and record every 0 times.008Mpa signal pressure corresponding to the stroke value, the actual pressure ━ the stroke relationship and the theoretical value of the nonlinear deviation should be ≤1%;
7 forward and reverse stroke variation test: the same as the nonlinear deviation test method, the actual forward and reverse pressure ━ in the stroke relationship, the cylinder piston under the same pressure value of the maximum difference should be less than 1% of the maximum difference between the cylinder piston;
