Lubrication characteristics of dual piston ring in bent-axis type piston pumps

• Published in: Journal of mechanical science and technology Vol. 24; no. 6; pp. 1363 - 1368
• Main Authors: Cho, IhnSung, Beak, IlHyun, Jo, JaeCheon, Park, JuMi, Oh, SeokHyung, Jung, JaeYoun
• Format: Journal Article
• Language: English
• Published: Heidelberg Korean Society of Mechanical Engineers 01.06.2010; Springer Nature B.V; 대한기계학회
• Subjects: Applied sciences; Control; Cylinder blocks; Cylinders; Drives; Dynamical Systems; Engine blocks; Engineering; Engines and turbines; Exact sciences and technology; Friction; Friction, wear, lubrication; Industrial and Production Engineering; Internal combustion engines: gazoline engine, diesel engines, etc; Lubrication; Machine components; Mechanical Engineering; Mechanical engineering. Machine design; Piston pumps; Piston rings; Pistons; Speed variators, torque converters. Hydraulic drives and controls, pneumatic drives and controls, fluids and components, hydraulic motors, pneumatic motors; Vibration; 기계공학; Piston ring; Elasto-hydrodynamic lubrication (EHL); Friction force; Oil hydraulic piston pump; Hydraulic oil; Leak; Engine cylinder; Layer thickness; Optimization; Hydraulic pump; Lubricating film; Variable section; Piston pump; Friction; High speed; Shaft; Internal combustion engine; Elastohydrodynamic lubrication; Tribology
• ISSN: 1738-494X; 1976-3824
• DOI: 10.1007/s12206-010-0342-3

The bent-axis type of piston pump driven by the piston rod works by the piston rod driving the cylinder block; because of this the taper angle of the piston rod and the swivel angle between the cylinder block and the shaft are important design factors. If these factors cannot satisfy the conditions for optimum design, the friction loss between the cylinder bore and the piston increases, and the pump can fail to work under conditions of severe friction and wear. Since the piston reciprocates in the cylinder bore with high velocity, at the same time rotating on its own axis and revolving on the center of the cylinder block, a decrease of the volume efficiency is generated because of the leakage between the cylinder bore and the piston. Therefore, to prevent this, the piston ring is designed to be at the end of the piston, and the friction characteristics between the piston ring and the cylinder bore require further research due to their great influence on the performance of the piston pump. Thus, in this paper, the elastohydrodynamic lubrication (EHL) analysis of the film thickness, the pressure distribution, and the friction force, have been studied between the piston ring and the cylinder bore in the bent-axis type of piston pump. The analyzed results show that the friction force is influenced by the rotating speed and the discharge pressure.