Technology for Obtaining Asymmetries of Stereometric Shapes of the Sealing Rings Sliding Surfaces for Selected Anti-Wear Coatings 2020-01-2229
The article presents the methodology of obtaining asymmetric shapes of the sealing rings sliding surfaces. A very high product tolerance of 1 to 3μm stereometric shape was taken into account for various types of wear-resistant materials that meet the requirements of adhesion of the anti-wear coating to the substrate. In particular, an analysis was made of the possibilities of using various product technologies, a modification of the grinder intended for profile grinding of the sliding surface of the rings was carried out, and the process of ring machining was determined. Maintaining the stereometric shape of the sealing rings sliding surface similar to the axisymmetrical model, with a product deviation of no more than a few micrometers, for any measuring section in the cross section on the periphery of the ring, gives the opportunity to verify the impact of this shape on the parameters of oil film and friction loss. Experimental tests were performed determining the product quality of the asymmetry of ring shapes for selected anti-wear coatings. The article also presents the results of tests determining the functional parameters of the produced rings, i.e. measuring the clearance in the joint, the tangential force of the piston rings, controlling the quality of the rings by means of the light gap method, measuring the shape by using a profilograph. Tests of the microstructures of the metallographic specimens of the top layers of coatings were carried out, as well as the tests of transition layers and the ring base material prior to and after the running-in period with the use of a Scanning Electron Microscope (SEM) and an optical microscope.