Inspection preparation and appearance inspection of pneumatic actuator

1.所有测试用仪器均须提前30分钟通电预热；

1. All testing instruments must be powered on for preheating 30 minutes in advance;

2.试验气源压力要满足0.6±0.1Mpa；

2. The test air source pressure shall meet 0.6 ± 0.1Mpa;

3.执行机构外观无明显损伤，导气铜管无明显瘪痕且装配牢固；

3. The appearance of the actuator is free of obvious damage, and the air guide copper pipe is free of obvious dent and firmly assembled;

4.位置变送器连接螺杆长度符合被检执行机构型号的技术要求；紧固在变送器轴上的连杆与连接螺杆所构成的平面应垂直于水平面；

4. The length of the connecting screw of the position transmitter shall meet the technical requirements of the actuator model to be tested; The plane formed by the connecting rod and connecting screw fastened on the transmitter shaft shall be perpendicular to the horizontal plane;

气动执行器的检验标准及方法

Inspection standards and methods for pneumatic actuators

1.将气动执行机构固定于校验台上，分别接好气源、控制气源和位移检测连杆；将校验台上仪表调校准确；

1. Fix the pneumatic actuator on the calibration bench, and connect the air source, control air source and displacement detection connecting rod respectively; Calibrate the instruments on the calibration bench accurately;

2.机械零点校准：输入4mA电流信号（0%），控制气信号应为0.02Mpa，此时气缸活塞行程应为零；如果不为零，可通过调整调零螺杆上的螺帽调整零点（零点高了紧螺帽）；零点和量程需要反复调整；零点误差要≤1%；

2. Mechanical zero calibration: input 4mA current signal (0%), the control gas signal should be 0.02Mpa, and the cylinder piston stroke should be zero at this time; If it is not zero, the zero point can be adjusted by adjusting the nut on the zero adjusting screw (the zero point is higher than the tightening nut); The zero point and range need to be adjusted repeatedly; Zero error shall be ≤ 1%;

3.机械满量程校准：输入20mA电流信号（100%），控制气信号应为0.10Mpa，此时气缸活塞行程应为上限值；如果不为上限值，可通过调整量程拉簧的松紧来调整量程（量程小了松拉簧，量程大了紧拉簧）；零点和量程需要反复调整；满量程误差要≤1%；

3. Mechanical full range calibration: input 20mA current signal (100%), the control gas signal should be 0.10Mpa, at this time, the cylinder piston stroke should be the upper limit value; If it is not the upper limit value, the range can be adjusted by adjusting the tension of the tension spring of the range (the range is smaller than the tension spring, and the range is larger than the tension spring); The zero point and range need to be adjusted repeatedly; Full scale error shall be ≤ 1%;

4.机械量程中点定位：零点和量程调准后，输入12mA电流信号（50%0.06Mpa，），调整位置变送器连接杆的位置，使其在该点要保持与水平面垂直；

4. Positioning of the midpoint of the mechanical measuring range: after the zero point and measuring range are adjusted, input a 12mA current signal (50% 0.06Mpa,), and adjust the position of the connecting rod of the position transmitter to keep it perpendicular to the horizontal plane at this point;

5.全行程偏差校准：输入控制气信号0.02Mpa（0%），然后逐渐增加输入信号0.036Mpa（20%）、0.052Mpa（20%）、0.068Mpa（60%）、0.084Mpa（80%）、0.1Mpa（100%），使气缸活塞走完全行程，各点偏差均要≤1.5%；

5. Full stroke deviation calibration: input the control gas signal of 0.02Mpa (0%), then gradually increase the input signals of 0.036Mpa (20%), 0.052Mpa (20%), 0.068Mpa (60%), 0.084Mpa (80%), 0.1Mpa (100%) to make the cylinder piston travel fully, and the deviation at each point shall be ≤ 1.5%;

6.非线性偏差测试：输入控制气信号0.02Mpa（0%），然后逐渐增加输入信号直0.10Mpa（100%），再将信号降为0.02Mpa（0%），0.008Mpa使执行机构走完全行程，并记录下每增减信号压力对应的行程值，其实际压力━行程关系与理论值之间的非线性偏差要≤1%。

6. Nonlinear deviation test: input the control gas signal of 0.02Mpa (0%), then gradually increase the input signal to 0.10Mpa (100%), then reduce the signal to 0.02Mpa (0%), 0.008Mpa to make the actuator travel fully, and record the travel value corresponding to each increase or decrease of signal pressure. The nonlinear deviation between the actual pressure travel relationship and the theoretical value should be ≤ 1%.