The main reason of vacuum pump scaling is that the water quality and operating temperature of circulating water exceed a certain index. Among the water quality indexes, the hardness of water has the greatest influence. For this reason, it is necessary to control the water circulating temperature as much as possible.

1. Hardness of circulating cooling water

The operation process of circulating water in vacuum pump is very similar to that of boiler water in low pressure hot water boiler. Therefore, according to the water quality standard of hot water boiler to manage the water quality of vacuum pump can not only prevent the vacuum pump from scaling, but also prevent the vacuum pump from corrosion.

Most of the circulating water systems of vacuum pumps are open circulation systems with high backwater rate. In the case that ion exchange equipment is not used for water treatment due to capital and other reasons, a softened water tank and a high water tank are generally used to supply water to the vacuum pump.

2. Temperature control of circulating cooling water

From the above analysis, it can be seen that the difference between the water ring temperature in the vacuum pump and the water temperature in the softening pool is an important factor leading to scaling. Therefore, increasing the circulating water supply and improving the cooling effect is an important guarantee to minimize the scaling rate.

Therefore, in the process of circulating cooling water operation, it is necessary to monitor the return water temperature and quantity of each pump, so as to ensure the normal water supply of each pump and the regulation that the return water temperature does not exceed 40 ℃. The water supply can be controlled by valves. If the return water temperature exceeds the specified value, low-temperature cold water should be added or other cooling methods should be used to reduce the temperature of softened water in the softening pool.

3. Wash the pump body regularly

The water ring vacuum pump body drainage gate valve, in addition to the normal discharge of water in the pump, can also use the pump body running water pressure to wash the dirt and water slag in the pump regularly during operation. On the one hand, it can prevent dirt accumulation, on the other hand, it can also prevent water slag from transforming into scale.

The scaling problem of vacuum pump has its complicated formation mechanism, and the correct analysis of water quality index and operation parameters is the key to find out the correct preventive measures. In addition to water temperature control and periodic flushing pump, water treatment is the most important link to prevent the pump from scaling.