An adjustable oil film thickness test rig for detecting lubrication characteristics of slipper/swash-pair in piston pumps

Purpose The purpose of this paper is to propose an adjustable oil film thickness test rig for detecting lubrication characteristics of the slipper. The mathematical analysis of lubrication is introduced. Based on the results from the test rig, the results comparison from test rig and mathematical analysis is carried out. Design/methodology/approach This paper introduces a mechanism which can adjust the oil film thickness between the slipper and swash-plate. Feasibility is ensured, and the accuracy of test rig is guaranteed by the three-coordinate measuring machine. Three displacement sensors show the oil film thickness and its shape. The reacting force and torque resulting from oil film can be achieved by three S-type force sensors and a torque sensor, respectively. Findings The relative error of the reacting force is small. The relative error reduces and is acceptable when the deformation of retainer is taken into account. The thickness and tilt angle of oil film have less effect on the reacting force. However, they are significantly impact on torque. Originality/value The test rig proposed in this paper is able to adjust the oil film thickness, which is used to detecting the lubrication characteristics in pump design. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2020-0166/

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Lubrication characteristics of the worn slipper in the slipper-swashplate pair

Industrial Lubrication and Tribology ◽

10.1108/ilt-07-2021-0241 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Haiji Wang ◽

Guanglin Shi

Keyword(s):

Surface Roughness ◽

Film Thickness ◽

Design Methodology ◽

Reynolds Equation ◽

Thickness Distribution ◽

Operating Conditions ◽

Test Rig ◽

Content Type ◽

Oil Film ◽

Lubrication Characteristics

Purpose This paper proposes the lubrication characteristics of the worn slipper in the slipper–swashplate pair. The mathematical analysis of lubrication characteristics of slipper with the measured surface roughness distribution is introduced. Based on the results from the test rig, it carries out the result compassion in different operating conditions. Design/methodology/approach This paper introduces the measured surface roughness distribution of new and used slippers and generates the oil film thickness distribution with it. An average flow Reynolds equation of the pressure distribution is introduced too. The experimental results are carried out on a novel adjustable oil film thickness test rig. Findings The surface roughness of the worn slipper enlarges the reacting force and torque only if the oil film thickness is small. When the ratio of oil film thickness to the root mean square of surface roughness is much smaller than 3, the influence of it on torque is obvious. Originality/value Different surface roughness of worn slipper proposed in this paper has an influence on the lubrication characteristics. As the slipper is worn after a period of use, the changed lubrication characteristics should be considered in the slipper design.

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A thermal EHL investigation for size effect of finite line contact on bush-pin hinge pairs in industrial chains

Industrial Lubrication and Tribology ◽

10.1108/ilt-10-2019-0448 ◽

2020 ◽

Vol 72 (5) ◽

pp. 695-701

Author(s):

Mingyu Zhang ◽

Jing Wang ◽

Peiran Yang ◽

Zhaohua Shang ◽

Yi Liu ◽

...

Keyword(s):

Film Thickness ◽

Peer Review ◽

Contact Zone ◽

Line Contact ◽

Equivalent Radius ◽

Content Type ◽

Oil Film ◽

Finite Line Contact ◽

Finite Line ◽

Thermal Ehl

Purpose This paper aims to study the influence of the dimension change of bush-pin on the pressure, oil film thickness, temperature rise and traction coefficient in contact zone by using a thermal elastohydrodynamic lubrication (EHL) model for finite line contact. Concretely, the effects of the equivalent curvature radius of the bush and the pin, and the length of the bush are investigated. Design/methodology/approach In this paper, the contact between the bush and pin is simplified as finite line contact. The lubrication state is studied by numerical simulation using steady-state line contact thermal EHL. A constitutive equation Ree–Eyring fluid is used in the calculations. Findings It is found that by selecting an optimal equivalent radius of curvature and prolonging the bush length can improve the lubrication state effectively. Originality/value Under specific working conditions, there exists an optimal equivalent radius to maximize the minimum oil film thickness in the contact zone. The increase of generatrix length will weaken the stress concentration effect in the rounded corner area at both ends of the bush, which can improve the wear resistance of chain. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2019-0448.

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