A Study on the Friction Reduction of Seal Ring for Automatic Transmission by Applying Surface Texture

Abstract

Texturing on sliding surface of resin seal ring was attempted to improve lubrication in this study. Numerical analysis of hydrodynamic flow at the sliding surface was conducted by Reynolds equation using the finite differential method. Frictional torque was measured at various sliding speeds and pressures and the oil film thickness was measured using LIF (laser-induced fluorescent) technique. Theoretical and experimental results are discussed and compared. The results show that the developed textured seal ring can be used at higher pressures and sliding velocities compared to a standard design thanks to the better lubrication that results from the hydrodynamic structures. Moreover, the textured seal rings show remarkably low frictional torque. Compared to conventional rings, friction is reduced by up to 70% with optimized texture dimensions.

Keywords

• seal ring
• surface texture
• low friction
• oil film thickness
• numerical analysis
• lif method