Repair of vacuum pumps of vane-type by modernization of end seals

The article is devoted to the issues of modernizing the design of a vane-type vacuum pump, to increase the efficiency of their work. The main reason for sending pumps for repair is a decrease in their supply, which for most pump brands occurs after 800-900 hours of operation. A decrease in feed is an increase in the end gas flow as a result of an increase in the end clearance due to wear. To solve this problem, a modernized design of a vane-type vacuum pump was proposed. The essence of the mo-dernization lies in the fact that in addition end plates are installed in the body, rotating together with the rotor in special grooves of the body. However, in connection with the modernization, a number of theoretical and practical issues arise, the solution of which is the main goal of this article. When considering these issues, a theoretical approach and bench tests were used, both of a serial and a modernized pump. For bench tests, a converted stand was used for running in and testing vacuum pumps. In the course of theoretical calculations, the following issues were considered: drop in the vacuum pump flow as a result of modernization; reduction of end overflows of gas; reducing the speed of relative movement of the end surfaces of the rotor and vanes relative to the side covers. Also, bench tests of the vacuum pump were carried out before and after modernization. Analysis of the data obtained during the tests confirmed the effectiveness of modernization of the design of the vane-type vacuum pump at the repair stage. Decrease in theoretical flow by 5,1% as a result of pump modernization is compensated by a 2,22-fold decrease in end overflows. The end wear of the rotor, side roof and blades of the modernized pump is also significantly reduced. Bench tests of the pumps have shown that the operating time of the upgraded pump is 2,87 times higher before reaching the maximum flow, compared to the serial pump.