The phenomenon of oil leakage of the reducer is analyzed in detail, and various reasons for the oil leakage of the reducer are introduced emphatically. The problem of oil leakage of the reducer has been basically solved by carrying out corresponding transformation and prevention and control of the oil-leakage reducer.       The reducer plays an important role in industrial production. Due to the existence of the working environment, usage methods, maintenance methods and design defects, the reducer will have different degrees of oil leakage during operation. The oil leakage of the reducer not only pollutes the environment, causes a waste of lubricating oil, but even causes the gear failure of the reducer caused by lack of oil. How to effectively prevent the oil leakage of the reducer is an effective guarantee for the normal production of the enterprise. The survey shows that the oil leakage of the reducer mainly occurs at the observation hole, the joint surface of the box, and the input and output shaft holes. There are many reasons for the oil leakage of the reducer, but the main reasons are summarized as follows.       (1) Oil leakage caused by poor ventilation. Due to the limitation of the working environment of the reducer, it will cause the phenomenon of poor ventilation of the reducer and clogging of the ventilator. Once the gas in the reducer cannot be discharged normally, the temperature inside the reducer will rise rapidly. At this time, the air pressure in the reducer increases with the increase of the working temperature of the reducer, which will cause the lubricating oil in the reducer to leak from the gap under the action of pressure.       (2) Oil leakage caused by low installation accuracy. The reducer bears a huge dynamic load when it is started. Once the installation accuracy of the reducer does not meet the standard requirements, the bolts on the base of the reducer will become loose, which will aggravate the vibration of the reducer and make the sealing rings at the high and low speed shaft holes of the reducer Increased wear causes lubricating oil to flow out.       (3) Oil leakage caused by poor machining accuracy. Due to the existence of factors such as low machining accuracy of the mating surface of the reducer box, improper tolerance, and unsuitable assembly requirements, the possibility of oil leakage from the reducer will be formed.