ENSURING MAINTAINABILITY OF THE NITRATED CRANKED SHAFT WITH ELECTROEROSIVE PROCESSING OF NECKS
Results of the research aimed at providing maintainability of the nitrated cranked shaft are presented in this work. The analysis of operational reliability of KAMAZ engines with the nitrated cranked shaft showed high wear resistance of these shafts. At the same time, the teases arising at operation on necks of a shaft it is almost impossible to eliminate with the standard methods of processing because of the high hardness of a blanket, and the surface on the nitrated layer is impossible that leads to utilization of a shaft. Besides, thickness of the nitrated layer is smallest that allows to process a shaft no more, than on one repair size. Thereof, maintainability of the nitrated cranked shaft is the extremely unsatisfactory and considerably increases costs for operation of vehicles. So, at the average market price of a cranked shaft of 93 thousand rubles. The program of production of 50 thousand engines and level of annual rejection of 0,03 losses of consumers will make 697,5 million rubles. The possibility of a surface of necks of the nitrated shaft in operation requires removal of the nitrated layer with the minimum expenses of resources and time. One of the technologies meeting these requirements is the developed technology of repair with removal of the nitrated layer in the electroerosive way on depth of 0,4 mm in a condition of the main structure that provides possibility of induction training or a surface without emergence on cranked shaft of cracks, peelings, blistering. After that necks of a shaft strengthen TVCh and resurfacing in the conditions of manufacturer or build up with the subsequent polishing and polishing in the conditions of repair productions in the established sizes. The subsequent repolishing of necks on the established size allows to restore to 80% of cranked shaft with teases of necks. The offered technology showed the working capacity and efficiency at tests, is applicable both in the conditions of repair production, and in the conditions of manufacturer with use of the standard equipment with considerable economy of resources in comparison with the existing repair methods.