Classification of pneumatic actuators

1, the switch action of the actuator is driven by the air source, which is called DOUBLEACTING(double acting). Take DA series pneumatic actuator as an example: the output torque of gear bar actuator is obtained by the piston pressure (supplied by the air source pressure) multiplied by the upper pitch circle radius (lever). And low friction resistance and high efficiency. The output torque is linear for both clockwise and counterclockwise rotation. Under normal operating conditions, the recommended safety factor of the double-acting actuator is 25-50%.

2, single-acting actuator SPRINGRETURN(single-acting) switch action only the open action is driven by the air source, and the close action when the spring returns. In the application of spring return, the output torque is obtained in two different operating processes, and according to the stroke position, each operation produces two different torque values. The output torque of the spring return actuator is derived from the force (air pressure or spring force) multiplied by the force arm of the first condition: The output torque is derived from the air pressure entering the cavity to compress the spring, called the "air stroke output torque" in this case, the air source pressure forces the piston from 0 degrees to 90 degrees, resulting in a reaction force due to the compression of the spring. The torque gradually decreases from the maximum value at the starting point until it reaches the second condition: The output torque is derived from the spring recovery force acting on the piston when the middle cavity loses air, called the "spring stroke output torque" in this case, due to the extension of the spring, the output torque gradually decreases from 90 degrees to 0 degrees as described above, the single-acting actuator is designed on the basis of producing a balance torque in both conditions. In each case, by changing the relationship between the number of springs on each side and the air source pressure, it is possible to obtain an unbalanced moment, and in spring return applications two conditions can be obtained: gassing on or gassing off. Under normal operating conditions, the recommended safety factor of the spring return actuator is 25-50%.

Pneumatic actuator features: 1, compact double piston gear, rack type structure, accurate engagement, high efficiency, constant output torque. 2, aluminum cylinder, piston and end cover, compared with the same specifications of the structure of the actuator weight is the lightest. 3, the cylinder is extruded aluminum alloy, and by hard anodizing treatment, the inner surface texture is hard, strength, high hardness. The sliding bearing made of low friction material avoids direct contact between metals, has low friction coefficient, flexible rotation and long service life. 3, pneumatic actuator and valve installation, connection size according to international standards ISO5211, DIN3337 and VDI/VDE3845 design, can be interchangeable with ordinary pneumatic actuators. 4. Air source hole meets NAMUR standard. 5. The assembly hole of the bottom shaft of the pneumatic actuator (in accordance with ISO5211 standard) is double square, which is convenient for linear or 45° Angle installation of the valve with square rod. 6, the top of the output shaft and the top hole meet the NAMUR standard. 7. The adjustment screws at both ends can adjust the opening Angle of the valve. 8, the same specifications have double acting, single acting (spring return). 9, according to the need to choose the direction of the valve, clockwise or counterclockwise rotation. 10, according to user needs to install solenoid valve, positioner (opening indicator), return device, various limit switches and manual operation devices.