In many applications, the main factor affecting the ultimate pressure of the vacuum system is the parameters of the high vacuum pump used. However, the characteristics of the vacuum system are not only determined by the high vacuum pump, but also by the compatibility of the backing pump and the entire pump unit to a large extent.
The vacuum pump or pump unit supports the air flow emitted by the vacuum system. If processing gas is added to the vacuum process, the gas flow rate is determined by the processing gas flow rate. On the contrary, if the vacuum system should reach the low pressure without adding processing gas, the gas throughput is mainly determined by the gas discharged from the inner surface of the vacuum system.
Choose the right backing pump
If you want to select a backing pump for a pump unit, the pressure generated by the pump must be less than the maximum fore vacuum pressure of the high vacuum pump used. This maximum front vacuum pressure can be found in the specifications of each turbo molecular pump, and its names include “maximum front vacuum”, “maximum fore vacuum” or “front pressure”. There are modern turbo molecular pumps that can operate at high front vacuum pressures greater than 20 mbar, depending on their structure and manufacturer. Therefore, the possibilities of choosing a pump from the standard backing pumps provided are almost unlimited. This does not limit the choice of standard backing pumps. Many backing pumps can generate this front vacuum pressure directly discharge to the atmosphere, such as oil-lubricated rotary vane vacuum pumps, compact diaphragm pumps, or high-performance dry vacuum pumps.
The following is an introduction to the knowledge of vacuum units. If you want to know more about vacuum unit products, please click to contact us.
The vacuum pump unit can install a spring vibration isolator if there is vibration.
When there is vibration in the vacuum pump unit, attention please, it should be install spring isolators. In particular, it is choice the style of the spring vibration isolator of the vacuum pump unit; in general, the self-supporting spring damper is also selected. In terms of its advantages, it is because its structure is relatively simple, and its cost is relatively low; the spring is exposed, which is convenient for us to observe the state of the spring at any time.
The springs that need to be replaced should be disposed of in advance, and in this regard, it can also avoid the phenomenon of excessive damage to the spring due to the sudden settlement of the vacuum pump unit and the equipment damage and the breakage of the pipeline.
When the vacuum pump unit is vibrate, you should to install a spring isolator. In fact, it is necessary to pay more attention to the choice of spring. Under normal circumstances, the spring selected by the shock absorber manufacturer must meet the following requirements. The diameter of the spring should be no less than 0.8 times its height under the rated load; the spring needs to have a certain extra stroke, and the vortex flow meter should at least be equal to 50% of the rated static deflection; the horizontal stiffness of the spring is at least 100% of the straightness, and the stability of the shock absorber can also be guaranteed at this time.
When the vacuum pump unit has a vibration phenomenon, choose to install a spring isolator. At this time, you must also pay attention to the choice of the deflection of the spring damper. Generally speaking, the rated deflection (rated compression amount of the spring) of the spring damper provided by its damper manufacturer is generally 25MM (the self-frequency value is about 3-4HZ).
Speaking of the deflection on the spring vibration isolator, it can be directly applied to the vibration isolation of the vacuum pump unit at 650 rpm. And when the vacuum pump unit is in operation, when its speed is lower than 650rpm, we actually recommend the use of spring isolators with a deflection below 40. In this way, the vibration of the equipment can also be reduced, so that noise can also be avoided.