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Vacuum pumps mainly include water ring pumps, reciprocating pumps, slide valve pumps, rotary vane pumps, roots pumps and diffusion pumps. At this stage, these pumps are indispensable main pumps in the application of vacuum technology in various industries of China's national economy. In recent years, with the sustained and rapid development of China's economy, the downstream application field related to vacuum pump has always maintained a rapid growth momentum. At the same time, driven by the continuous development of vacuum pump application field and other factors, China's vacuum pump industry has realized a sustainable and stable development trend.

According to the in-depth investigation and investment forecast analysis report of China's vacuum pump manufacturing industry from 2013 to 2017 [1], the entry and success of foreign enterprises have become an indisputable fact in China's vacuum pump market. The distribution of vacuum in Japan, the expansion of Laibao in China, texel group South Korea Youcheng and other international famous manufacturers are also looking for partners to build manufacturing bases in China. They have a big appetite and are likely to swallow the vacuum pump market. In recent years, although some domestic enterprises gradually rise rapidly and occupy a relatively leading position in the vacuum pump market, the vast majority of enterprises have poor R & D ability. Compared with their foreign counterparts, high-end products are still at a disadvantage in technology.

The vacuum drying oven has requirements for the materials to be dried. First, it can not contain a large amount of water, and second, it can not contain organic compounds; While vacuumizing, they will be pumped into the body, resulting in a series of abnormal reactions, which will affect the service life of the pump. If the material contains water or organic solvent, liquid water filter and condenser must be added to play a filtering role. While using the vacuum drying oven, we must also strengthen the maintenance of the vacuum pump, change the oil of the vacuum pump in time and prolong its service life. According to the analysis report on in-depth investigation and investment forecast of China's vacuum pump manufacturing industry, the dry vacuum pump is still in its infancy in China at this stage, and the substitution of domestic for import will become a trend in the future. Dry vacuum pump needle will have a great effect on the yield of the process. It is also a trend for dry pump to replace the existing water pump and oil pump.