Theoretical research of the technology of finishing cylinders with antifriction materials

The article analyzes the research aimed at the use of various materials, additives and additives to oils. It is established that their application is mainly limited to the stages of operation, bench and operational running-in. The use of antifriction materials at the stage of processing the parts of internal combustion engines, limiting the resource, is small, despite the fact that such treatment reduces the running-in time and improves the finish of the friction surfaces. Theoretical calculation of the parameters of the working surface of the engine cylinder liner during their finishing using special antifriction materials showed a 2-fold increase in the bearing surface (from 0.2 to 0.4 of the nominal surface area at the level of the middle line of the profile) and a roughness of 0.27 μm, which is close to the values after the bench run-in. This proves the possibility of using this treatment in order to reduce the time of preparation of CNG and improve the characteristics of the surfaces to be worked. It is established that the finishing of engine cylinder liners with antifriction materials should be carried out at the contact pressure of the working tool (brass bars) on the surface of the sleeve 3 MPa, the speed of the working tool 5.5 m/s, the processing time of the sleeve 20 min. Finishing of sleeves with use of compositions TSK-B100 + SURM-KV, SURM-UO and RVS allows to reduce mechanical losses on friction in TsPG by 5-19% at the beginning of process of running in after processing in comparison with mechanical losses at the end of cold running in without finishing sleeves; to obtain the roughness parameters after finishing the same as after cold running in without additional processing of the sleeves; increase the bearing surface by 2 - 2.5 times (from 0.2 - 0.25 to 0.4 - 0.5 of the nominal surface area at the level of the middle line of the profile), which confirms the calculated data. The final treatment of sleeves with compositions based on antifriction materials TSK-B100 + SURM-KV, SURM-UO and RVS allows to provide values of parameters of a working surface of sleeves (reduction of roughness, increase of a basic surface) approaching their values after cold running in, therefore allows to increase contact loadings. in the connection "sleeve - piston ring" after this treatment and reduce the time of the bench run-in (to the values required for the attachment of other engine connections).