How to select vacuum pump
1. Vacuum degree required by the process
The working pressure of vacuum pump should meet the requirements of process working pressure, and the vacuum degree should be higher than that of vacuum equipment by half to one order of magnitude. (for example, the vacuum degree of 100 Pa (absolute pressure) is required for the vacuum process, and the vacuum degree of the selected vacuum pump shall be at least 50 pa-10 PA). Generally, if the absolute pressure is required to be higher than 3300pa, the water ring vacuum pump is preferred as the vacuum device. If the absolute pressure is required to be lower than 3300pa, the water ring vacuum pump cannot be selected, and the rotary vane vacuum pump or the vacuum pump of higher vacuum level can be selected as the vacuum obtaining device.
2. Process required air extraction rate
The vacuum pump requires the air extraction rate (that is, the ability of the vacuum pump to discharge gas, liquid and solid under its working pressure), generally in m3 / h, L / s and m3 / min. The specific calculation method can refer to the following formula for self calculation and selection. Of course, the selection of vacuum pump is a comprehensive process, involving relevant experience and other factors.
Where: s is the pumping rate of vacuum pump (L / s)
V is the volume of vacuum chamber (L)
T time required to reach the required vacuum (s)
P1 is the initial pressure (PA)
P2 is the required pressure (PA)
3. Determine the composition of the object to be extracted
First, whether the object to be pumped is a gas, a liquid or a particle. If the gas to be pumped contains impurities such as water vapor or a small amount of particles and dust, the rotary vane vacuum pump should be carefully selected. If the vacuum degree is required to be high, a filter device should be added to filter before using the rotary vane vacuum pump as a vacuum obtaining equipment.
Second, it is necessary to know whether the object to be pumped has corrosion (acid or alkaline, what is the pH value?). If the gas contains acid-base corrosion or organic corrosion and other factors, it should be filtered or neutralized to select the rotary vane vacuum pump.
Third, is the object to be pumped contaminated with rubber or oil? For different media to be pumped, corresponding vacuum equipment should be selected. If there is a large amount of steam, particles and corrosive gas in the gas, it should be considered to install corresponding auxiliary equipment, such as condenser, filter, etc. on the air inlet pipeline of the pump (contact our corresponding technical engineers specifically).
Fourth, whether the noise, vibration and beauty of the vacuum pump affect the factory.
Fifth, as the saying goes, cheap is not good. When purchasing vacuum pump and vacuum equipment, priority should also be given to the quality of equipment, transportation, maintenance and repair costs, etc.