1.内燃机可靠性国家重点实验室,山东 潍坊 261061;2.潍柴动力股份有限公司，山东 潍坊 261061
Abstract：Aiming at the failure of mechanical seal of a diesel engine gear driven pump, the failure mode mechanism analysis and test are carried out. It can be found that the large fluctuation of pump speed is the main reason for the failure. In order to reduce the pump speed fluctuation, the optimized firing sequence and shock absorber matching are used to reduce the crank shaft speed fluctuation. Meanwhile，the vibration impact of high pressure oil pump, camshaft and other accessories can be reduced by optimizing gear system. The experimental results show that the improved scheme is effective, and the reliability of gear pump can be evaluated quantitatively by speed fluctuation, which provides a theoretical basis for reliability design of diesel engine.
Keywords:gear transmission; water pump; mechanical seal failure; speed fluctuation