Experimental investigation of friction behaviors for double-acting hydraulic actuators with different reciprocating seals

Abstract Investigation of friction force induced by seals is important in improving control accuracy and evaluating sealing performance for hydraulic actuators. An experimental apparatus was developed to measure the friction forces for hydraulic cylinders under different operating conditions based on position and chamber pressures measurements only. The effects of velocity, external load, seal diameter, and sealing profiles on steady state friction force of hydraulic cylinders were examined. In addition, the influences of amplitudes of velocity and acceleration on dynamic friction force were also highlighted. It was shown that the hydraulic actuator with combined piston seal demonstrates the highest friction force and is less sensitive to variation of load than that of Glyd ring and U-cup seal.