Abstract:The cam-roller pair is a key friction pair in the valve train of high-power marine engines.In addition to being subjected to spring force and inertial force,it is also subjected to extremely high pump pressure from the fuel injector,making the working conditions extremely harsh.In order to analyze the performance of this friction pair,a mixed thermal elastohydrodynamic lubrication model of the cam-roller pair under heavy load conditions of marine engines was established,and the oil film lubrication,frictional heating,and wear performance of the friction pair under the action of pump pressure were calculated.The results show that the pump pressure from the fuel injector significantly reduces the oil film thickness between the cam-roller friction pair and generates serious asperity contact.With the increase of ambient temperature,the oil film thickness and oil film temperature rise of the cam-roller pair will decrease,while the asperity contact pressure,frictional force,and frictional power will increase significantly.Roller slip will cause a decrease in the oil film thickness of the cam-roller friction pair,and also lead to an increase in oil film temperature rise,asperity contact pressure,and surface wear.