Effect of compound texture on lubrication and sealing performance of plunger pump

Abstract A type of compound texture combining micro‐dimple and variable‐depth groove was designed to improve sealing performance and reduce wear of the plunger couple in diesel engine. The simulation results indicate that moderate oil film thickness can be produced by compound texture to settle the lack of lubrication of groove mode. Meanwhile, higher hydrodynamic pressure is produced to improve sealing performance of a plunger couple, tackling the problem of relatively high leakage of micro‐dimple mode. The compound texture was fabricated on the plunger surface by laser surface texturing (LST) and the test results confirmed the improvement of lubrication and sealing performance. The basic tribological test result shows that that the deepest wear depth and average roughness were reduced by 72.4% and 22.6%, respectively. Meanwhile, the engine bench test result shows that the amount of fuel leakage was reduced by 73.1% as well.