Roughness optimisation of textured surface for the gap seal hydraulic cylinder

The circular micro-texture is constructed on the inner surface of the gap seal hydraulic cylinders. The coupling relationship of the surface roughness and micro-texture is studied and solved by the equivalent flow method. At the same time, the tribological experiment is carried out with 45 steel materials commonly used as hydraulic cylinders, and the testing results are compared. The results show that the roughness has a very significant effect on the frictional properties of the annular textured surface. The coupling effect is generated and makes the friction coefficient first decrease and then increase. There are optimal roughness and optimal gap which make the further improvement of the frictional properties on the cylinder surface. This helps to improve the response frequency of the hydraulic cylinder, thereby improving the hydraulic system efficiency. Also, it has positive effects on the improvement of the working efficiency in the hydraulic system.