This paper mainly introduces a kind of main equipment for pumping steam, which is composed of regulating valve, steam condenser, refrigeration unit and vacuum pump. When the gas to be pumped passes through the steam condenser, the refrigeration unit will cool the gas that needs to be pumped out mainly containing water vapor to a sufficiently low temperature so that most of the water vapor will be condensed into low-temperature liquid water, and the rest will be discharged A small amount of water vapor and non condensable gas are pumped out by vacuum pump. At present, many enterprises will choose the application of dry screw vacuum pump for water vapor.
As for the difference between water vapor and water vapor, I’m sure many people haven’t figured it out yet. EVP water ring vacuum pump manufacturer will give you a brief explanation.
Difference between water vapor and water vapor:
Water vapor: water in a specific space exists as a gas.
Water vapor: refers to the existence of water in a specific space in two states of gas and liquid.
Water vapor, short for water vapor, is the gas form of water (H2O). When water reaches the boiling point, it becomes water vapor. At sea level – standard atmospheric pressure, the boiling point of water is 99.974 ° C or 212 ° f or 373.15 ° K. When the water is below the boiling point, it can also slowly evaporate into water vapor. However, under extremely low pressure (less than 0.006 atmospheric pressure), ice will sublimate directly into water vapor. Water vapor may cause greenhouse effect, which is a kind of greenhouse gas.
There are many kinds of existing vacuum pumps. In the aspect of obtaining crude vacuum, there are liquid ring (water ring), rotary vane vacuum pump, slide valve vacuum pump, roots vacuum pump, dry vacuum pump, steam jet vacuum pump, vortex vacuum pump and screw vacuum pump. There are only water ring, water jet and steam jet vacuum pumps suitable for pumping steam, among which water ring vacuum pump is widely used because of its high mechanical efficiency and simple structure; other vacuum pumps are easy to be damaged due to the compressed condensed water and cannot work normally for a long time.
However, the water ring vacuum pump is not perfect when it is used to pump steam. Because the working performance of the water ring vacuum pump is greatly affected by the working water temperature, and the steam compressed by the water ring vacuum pump will release a lot of heat energy, which will significantly increase the working liquid temperature of the water ring vacuum pump, resulting in the cavitation problem of the water ring vacuum pump, the suction capacity greatly reduced and other problems (the actual suction capacity of a large number of water ring vacuum pump is reduced to less than 30% of the nameplate output ）, which affects the recycling of working water for water ring vacuum pump.
In order to solve the above problems, many people have put forward various solutions. For example, jet pump or mechanical pump is used to pressurize and / or pre cool the extracted gas; refrigeration device is used to reduce the working liquid temperature of water ring vacuum pump, etc. At present, a better solution is to adopt the technical route of dry screw vacuum pump.
Analysis on the structure of screw vacuum pump by vacuum pump manufacturer
The transmission shaft is connected with the active rotor, and the driven rotor is driven to rotate by the synchronous gear. A cooling water channel is opened on the shell to cool the temperature of the rotor and the exhaust port. The synchronous gear and the bearing are lubricated by oil. The bearing and the shell are sealed by seals to achieve the effect of no oil. The structure of dry screw vacuum pump is similar to that of oil-free screw compressor in sealing and lubrication. Generally, mechanical seals are used at the exhaust end of vacuum pump, and double lip seals are commonly used at the inlet side. In the way of transmission, the general purpose is to connect the motor directly with the rotor by coupling, and a few are driven by belt or drive chain. Due to no internal compression process, the exhaust temperature of constant pitch screw pump is very high. If the cooling effect is not good, the rotor and casing will be deformed, which will affect the pumping effect. Cooling the shell is an essential part, and water cooling is the most common method. Cooling water can be passed through the shell body and the outside of the bearing to cool the shell and then the rotor.
After fine dynamic balance correction, the two screws are supported by bearings and installed in the pump housing. There is a certain gap between the screws. Therefore, when the pump is working, there is no friction between them, the operation is stable, the noise is low, and the working chamber does not need lubricating oil. Therefore, the dry screw pump can pump out the gas occasions with a large amount of water vapor and a small amount of dust, with higher ultimate vacuum and lower power consumption, It has the advantages of energy saving and maintenance free.
Special dry screw vacuum pump for water vapor. If you still don’t understand these contents, or want to know more about vacuum pump products, you can directly consult us.