Two body abrasive wear and frictional characteristics of sealing elastomers under unidirectional lubricated sliding conditions

Abstract

Since abrasion is a common cause of seal failures, understanding the mechanisms of abrasion of an elastomer in the presence of lubricants is of importance in sealing applications. In this research a block on ring configuration was used to study the influence of lubrication on the two body abrasion of several commonly used sealing elastomers (two acrylonitrile butadiene rubbers, an acrylic rubber and a fluoro rubber). The friction force and the abrasive wear of the samples were measured and the worn surfaces and wear particles were investigated using an optical microscope. The tear strength of the elastomers before and after immersion in monoester oil as well as the oil absorption has been measured. Both scratches (parallel to the direction of sliding) and ridges (perpendicular to the direction of sliding) were observed on the worn surfaces of nitrile rubbers but the surfaces of acrylic and fluoro rubber were characterised by scratches only. The worn surfaces of nitrile rubbers were defined with more continuous ridges at lower sliding velocity and the presence of a lubricant in the contact reduced the continuous ridges. Examination of the wear particles shows that the wear particles (particularly for acrylic rubber) under dry sliding condition were aggregated, but the lubricant dispersed the wear particles and prevented aggregation. In most cases, abrasive wear of the elastomers under lubricated condition is higher than that under dry condition. The results show that the friction coefficient increased with increasing sliding velocity and decreased with contact pressure. Apart from the fluoro rubber, the friction coefficient as well as the tear strength of the elastomers decreased significantly in the presence of lubricant, particularly for acrylic rubber.

Experimental study of surface roughness on improving the tribological performance of sealing pairs in magnetorheological damper

“…This makes the O-ring to wear much faster than in a device that uses a conventional hydraulic oil [16]. Moreover, the fluid leakage caused by high friction loss between the sealing pairs limits the usage life and the performance of MR equipment [17]. To sum up, although the movement pattern of the MR damper is not much different from the traditional hydraulic cylinder, there is a great difference in wear mechanism between the sealing pairs.…”

Analysis of Sensitive Parameters Affecting Unlocking Force of Finger Lock in Landing Gear

“…Therefore, whether the landing gear lock mechanism can work normally is directly related to the safety of the aircraft [2], which is an important part of the landing gear design. During the use of the landing gear, the lock mechanism will gradually wear during the unlocking and locking process, resulting in the change of unlocking force [3]. If the unlocking force is abnormal, it will lead to the landing gear retraction failure, which will threaten the safety of aircraft takeoff and landing [4,5].…”

Wear analysis of finger locks with different design parameters for landing gear

“…3 If the wear is within the specified range, the lock mechanism can maintain normal working conditions. If it exceeds the upper limit of wear, the friction force of the friction pair formed by the lock mechanism will rise sharply, 4 resulting in a retractable failure of the landing gear. 5 The wear problem has been studied at home and abroad for a long time.…”