Vacuum pump maintenance is a repair technology. When the vacuum pump is running for a long time, the working efficiency of the vacuum pump is reduced or the vacuum pump stops due to friction and internal and external forces. At this time, the worn or broken parts need to be repaired and replaced. Moreover, the cylinder and rotor with high precision requirements are repaired to meet the requirements of improving the efficiency and performance of the vacuum pump. These steps are the overall embodiment of the maintenance technology of the vacuum pump.Vacuum pumpSeveral methods commonly used in vacuum pump maintenance1、 Boring cylinderBoring cylinder is a common maintenance method of dry pump. It is mainly aimed at the phenomenon of excessive wear of cylinder liner.The boring cylinder is mainly divided into the following steps:Rough boring - leave a machining allowance of 0.10mm for fine boringFine boring - leave honing allowance of 0.03mmHoning - achieve the specified size and surface roughnessCleaning - carefully clean the cylinder block, then put the matched piston into the cylinder to check the fit, and finally coat the cylinder with lubricating oil to prevent rust2、 Cleaning of pump bodyThis paper mainly introduces the cleaning process of oil vacuum pump. You may think that cleaning is a simple step. In fact, this step seems simple, but it is a very important process. In order to reduce costs, general manufacturers just flush the oil tank and pump head with gasoline or water. In fact, this is far from enough. The long-term operation of the oil vacuum pump under high temperature leads to the emulsification and carbonization of the vacuum pump oil, forming a thick substance attached to the oil tank and pump head. If it is not handled in time, it will remain in the vacuum pump and affect the performance and service life after maintenance. Therefore, to solve this problem, we must use special cleaning agent after ultrasonic cleaning.3、 Parts replacementReplace the original damaged or broken parts. In this process, the accuracy of parts is relatively important. The selection of parts needs to meet the accuracy of pump body assembly to prevent abnormalities after parts assembly.The failure of vacuum pump is often caused by improper daily use, so the daily operation and maintenance of vacuum pump is very important.