On the wear of plastic plain bearings
Plastic Bearings Plastic Bearings wear resistance depends on the wear resistance of the material itself, but the plastic sliding bearing wear is closely related to the following factors: the shaft material, hardness, roughness, bearing running speed, load and ambient temperature , humidity, etc.; as plastic plain bearings manufacturers, is constantly optimizing the wear resistance of plastic bearing materials and to provide users with the correct selection guidance; and as a user to follow the manufacture of plastic bearings commercial product manuals bearing on the selection of plastic and assembly instructions.
Any bearing is the most critical moment of start-up phase. At this point, the formation of lubricating film bearings have not started work, which is the most common situation. As slide bearing long as the load bearing of a work will have a slight bearing wear. In the start-up phase, minor wear more fully, they will wear with these small particles fill the outer surface of the shaft, so when low wear and tear can produce the best work of lubricating film. Starts, minor wear decreased rapidly, these changes had little impact on the size. After the start-up phase of continuous work, the wear rate of small and stable.
Any type of plastic plain bearings have a matching for the best working conditions, such as best fit the shaft material, roughness; best work pressure, speed, temperature, etc.; on the CSB-EP series of plastic bearing the best with the shaft material is hard chrome plated surface; roughness on the CSB for each type of plastic plain bearings on the shaft surface roughness requirements are not the same, we can see from Figure 3 CSB plastic plain bearings on the shaft of the roughness from Ra0. 1 to Ra1.6; while CSB-EP5 plastic bearing temperature is not the best at room temperature, EP5 at 160 ℃ in temperature friction and wear properties shown by the best.
Laboratory continues to CSB to imitate a variety of working conditions found in the test study, the work of plastic bearing wear occurs mainly in the form of the following:
Normal wear and tear - with bearings in the right place under conditions of use wear; this time bearing wear mainly for the initial phase of the work of the lubricating bearing material in the shaft surface to transfer the results, when the deputy after the establishment of the ideal lubrication of bearings the wear rate to slowly lower.
Crawl wear - the shaft surface roughness caused by the friction surface is too smooth crawling; shaft surface is too smooth, lubricated plastic bearing material in the fill can not be transferred to the axis of the formation of surface pits in the lubricating film, making the ideal friction can not be built; this increase when the coefficient of friction bearings, the required driving force is increased;
Furrow wear - the shaft is too rough friction surface scratches caused the phenomenon of the furrows; shaft surface height difference is too large, the transfer from the bearing surface to the formation of a solid lubricant material can not be the ideal smooth friction surface; substance of wear occurs at this time is the scratch of wear;
Bonding wear - bearing out the safe operation of the optical axis due to temperature or glue; optical axis in the bearing operating temperature exceeds the allowable temperature of the safe operation of the adsorption has taken place in the local softening of the bearing friction surface and the formation of wear.
Burns wear - the speed is too fast burns caused by friction surface wear; shaft bearings run faster than the speed allowed by the friction surface will cause friction because the friction heat from a sharp rise in students, a sharp increase in the friction heat of friction a quick surface burns.
Plastic sliding bearing wear course is inevitable phenomenon occurs in the plastic sliding bearing performance have been identified, we can only follow the possible use of each different type of bearing rule, the plastic sliding bearings to minimize wear and tear, which the performance of the plastic bearing play to the best. |