The Influence Of The Hydraulic Cylinder Piston Seal Structure On Start-up Pressure And Internal Leakage

For common hydraulic cylinder, the seal structure of the piston should reduce the opening pressure on the basic of ensuring the low leakage; for high frequency response and low friction hydraulic cylinder, the seal structure of the piston should not only reduce the opening pressure, but also reduce the leakage. When the opening pressure is high, the nonlinear of the dead zone is big because of the mechanical friction, the response speed of the cylinder is low and the abrasion is severe; when the leakage is large, the volumetric efficiency of the hydraulic cylinder is low and its performance can not meet the requirements. therefore, the opening pressure and the leakage are conflicting, its design must according to the specific requirements.The most seal structure of hydraulic cylinder piston adopt the Glyd ring, this paper adopt the ABAQUS software to analyze the influent law of the structure parameters of the Glyd ring(the chamfer of the groove, the width of the groove, the depth of the groove and the gap of the seal) on the opening pressure and leakage.The analysis results indicate the following influent law of the structure parameters of the Glyd ring on the opening pressure and leakage:(1) In a constant medium pressure, when the chamfer of the groove increase, the contact pressure between the contact surface increase, the opening pressure increase and the leakage reduce; when the width of the groove increase, the contact pressure between the contact surface reduce, the opening pressure reduce and the leakage increase; when the depth of the groove increase, the contact pressure between the contact surface reduce, the opening pressure reduce and the leakage increase; when the gap of the seal increase, the contact pressure between the contact surface reduce, the opening pressure reduce and the leakage increase.(2)In a certain chamfer and width and depth of the groove, when the medium pressure increase, the contact pressure between the contact surface reduce, the opening pressure increase and the leakage reduce. In a certain gap of the seal, when the medium pressure increase, the contact pressure between the contact surface increase, the opening pressure increase and the leakage reduce.Finally, the verify experiment of the influent law of the structure parameters of the Glyd ring on the opening pressure and leakage is designed, and the numerical analysis system of the influence of piston Glyd ring seal structure of hydraulic cylinder on the start-up pressure and leakage is developed.