According to the limit pressure to determine the type of the main pump, the general selection of the limit pressure of the main pump is half to an order of magnitude lower than the limit pressure of the vacuum chamber. When selecting the main pump according to the working pressure of the vacuum unit, the EVP vacuum pump manufacturer suggests that the working process environment of the main pump should be correctly selected, and within its working pressure range, all gas produced in the process of the vacuum chamber should be eliminated. Therefore, the working pressure in the vacuum chamber must be within the pumping pressure range of the main pump.
In the selection of vacuum pump according to the volume of vacuum chamber and pumping time, the volume of vacuum chamber has an effect on the time when the system reaches the limit vacuum. When the pumping time is fixed, the larger the volume of the vacuum chamber is, the larger the pumping speed of the main pump is. The correct combination of pumps, vacuum pump manufacturers because of the different performance of various vacuum pumps, so sometimes choose a pump can not meet the pumping requirements, need several pumps combined, complement each other to meet the pumping requirements.
Requirements of vacuum system if the vacuum system strictly requires no oil, all kinds of oil pumps shall be selected as the main pumps. If the requirements are not strict, oil pump can be selected, and then some anti oil pollution measures, such as adding cold trap, baffle plate, oil trap, etc., can also meet the requirements of clean vacuum.
When selecting the vacuum pump for the composition of the extracted gas of the vacuum unit, we should know the composition of the extracted gas and select the corresponding vacuum pump for the composition of the extracted gas. If the gas contains corrosive gas, particle dust, etc., dry vacuum pump, water ring vacuum pump,corrosion-resistant vacuum pump, etc., or auxiliary equipment shall be installed on the air inlet pipe of vacuum pump.
Key points for purchasing water ring vacuum pump:
1. Vacuum degree
It is the limit vacuum required by the process environment you use;
2. Pumping speed
It is the speed of vacuuming, generally how many cubic meters of space an hour;
For the brand requirements of vacuum pump, generally, the quality of imported brands is more stable than that of domestic brands, but the price is 3-5 times of that of domestic brands, so it should be positioned according to its own needs;
4. Motor power and power supply voltage
Motor power refers to the greater energy consumption of pump power under the same vacuum degree and pumping speed. Power supply voltage refers to three-phase or single-phase, 220-380-110. Many foreign production pump voltage is 110V or three-phase 220V,
5. Other factors
Including the size of the vacuum pump interface, the length, width and height of the installation volume, etc. These are the factors that need to be tested during the purchase.
6. Special industry special pump
Some special industries, such as auto parts processing, high temperature, corrosive places, explosion-proof and so on, need to purchase special type pumps, which are generally customized by the manufacturer, and need to explain customization in advance.
In the selection of vacuum pump according to economic indicators, different types of vacuum pump have different energy characteristics, equipment purchase cost and maintenance cost. Therefore, in the process of selecting the main pump of vacuum system, enterprises need to match the requirements of real air system reasonably according to their own budget situation and working condition environment. There are many factors to be considered in the selection of vacuum unit. Therefore, EVP water ring vacuum pump manufacturers think that they should pay attention to all aspects mentioned above and pay more attention to them.