Hydraulic actuator features:
       Hydraulic actuators are divided into double-acting and single-acting (spring reset), two separate cylinder, the output torque, flexible balance of action; hard chrome plated piston rod, with good wear resistance All sliding parts with a non-lubricating shaft guide ring to reduce the friction coefficient and prolong the service life of the U-shaped curve of the actuator output torque is more suitable for large-diameter ball valve, butterfly valve, such as the opening and closing of the valve stroke, Closed and adjusted, can also be used for other occasions rotary motion, is to achieve the ideal industrial automation control device. 

       Selection of hydraulic actuators, the first to determine the valve opening and closing torque, and then use the valve fluid medium to increase the safety value. Adds 20% safety value to clean, lubricated media; 25% safe for steam or non-lubricated media; 60% safe for non-lubricated dry media; Non-lubricated particulate media with gas Increase 100% safety value. Then according to the working pressure of gas source, find the double-acting or single-acting output torque meter, it is feasible to the accurate actuator model. In the single-acting output torque table, the minimum spring torque is the torque when the valve is closed and the spring torque is the torque when the valve is opened.