Dry screw vacuum pump is a kind of vacuum pumping equipment that uses a pair of screws to rotate synchronously in the pump casing at high speed and reverse to produce suction and exhaust. The working principle of the dry screw vacuum pump is: the use of gear transmission to synchronize and reversely rotate mutually meshing without touching the left screw and the right screw for high-speed rotation, and the pump casing and the meshing propeller spiral groove are divided into multiple spaces and form multiple stages. , The gas is transported in equal grooves, but there is no compression. Only the spiral structure at the end of the screw has a compression effect on the gas, and finally forms a vacuum.

1. The advantages of dry screw vacuum pumps
When dry screw vacuum pumps work, there is no friction between each other, the operation is relatively stable, the noise is relatively low, and the working chamber does not need lubricating oil. Therefore, the dry screw vacuum pump can pump out the gas containing a large amount of water vapor and a small amount of dust. The ultimate vacuum is higher, the power consumption is relatively low, and it has the advantages of energy saving and maintenance-free. It is an upgraded version of the oil-sealed vacuum pump.
2. Working principle of dry screw vacuum pump
The working principle of the dry screw vacuum pump is mainly to use the gear drive to synchronize the reverse rotation of the left screw and the right screw, which are meshed and do not touch each other, to rotate at a high speed. The pump casing and the meshing propeller spiral groove are divided into multiple spaces to form multiple In the first stage, the gas is transported in equal grooves without compression. Only the spiral structure at the end of the screw can compress the gas. The pressure gradient can be formed between the stages of the screw to disperse the pressure difference and increase the compression ratio. The gaps of each part and the pump speed have a great influence on the performance of the pump. When designing the gap of each part of the screw, the expansion, processing and assembly accuracy and working environment should be considered. The dry screw vacuum pump does not have an exhaust valve like the roots vacuum pump.

3. Structural principle of dry screw vacuum pump
The dry screw vacuum pump is a vertical structure, the air inlet is at the top, the air outlet is at the middle, and the lower part is the motor and lubricating oil pool. The screw rotor is hollow and has a cantilever support structure. The synchronous transmission gear is located under the bearing support. The variable frequency motor is connected to the active rotor through a coupling, the gas path of the pump is short, and the vertical structure is more advantageous for removing dust-containing gas. The pump casing is cooled by water, and the pump maintenance is also convenient.

Dry screw vacuum pump chooses appropriate simpler screw thread section, then its advantage is that it is simple to manufacture, can ensure high processing accuracy, and is easy to balance. According to its working principle, we can clearly realize that the dry screw vacuum pump has the advantages of high ultimate vacuum, low power consumption, energy saving, and maintenance-free.