Experimental research of conditions of cylinder oil supply in high-speed four-stroke internal-combustion engine

Abstract

The research is relevant because oil supply processes in the cylinders of four-stroke piston engines with traditional cranking mechanism and combined lubricating system are understudied. The research aims to receive the experimental data on pattern of motor oil distribution by circumference of cylinder for the specified type of internal-combustion engine. The measurement method is based on organization of drainage and following quantity control of oil that is removed by piston rings from internal surface of the cylinder. Experimental device corresponding to this method represents the low-sized high-speed four-stroke air-cooled TMZ-450D diesel engine having a cylinder with six oil-catch through holes executed in its bottom support belt and supplied with thin-walled tubes. Tests were performed under rotation of crankshaft by means of outside source (balanced engine) with nominal speed. The oil filling of any first of six tubes was considered as a moment of ending for each experience. The quantity of oil in tubes was controlled by measuring of oil column length in every tube. During cranking both with air compression and without it, experiments show that quantity of motor oil removed by piston rings from non-loaded cylinder wall side in all cases is more by 15-18% than from the loaded one. Such pattern of oil distribution by circumference of a cylinder at which non-loaded side receives more oil than the loaded one, points to the infringement of principle of coordination between lubricating and loading conditions. That increases the risk of wear and bore scuffing in cylinder-piston unit. In spite of limitation by only one method and one object, the received results show the expediency of following studies of features of cylinder oil supply for the specified type of engines to increase their work reliability.