To meet these basic requirements - vacuum system

vacuum system refers to the vacuum pump through a pipeline, vacuum gauge, and all kinds of parts in an appropriate way to connect, to a certain degree of vacuum device. What are the basic requirements of vacuum system?

1。 To obtain the required in the pumping unit or studio ultimate vacuum and vacuum

ultimate vacuum is refers to the device in the absence of leakage and deflated to vacuum, vacuum degree of work refers to a device for vacuum degree of vacuum treatment can keep. In a vacuum process often release large amounts of gas, the vacuum degree of work will be much less than the ultimate vacuum. Extreme vacuum and vacuum degree of work has its own importance, they are from different aspects affect the quality of the device. For example, in the use of oxide cathode device of exhaust vacuum system, electricity 10 - 2 degassing and cathode electrode decomposition will produce a large number of degassing. If the vacuum degree of work is poor, electrode can be oxidized, cathode could activate is bad. However, when the device is in the end seal, basically do not have leakage and deflated, and device of the vacuum degree depends on the exhaust limiting vacuum of vacuum system.

2。 The time required to obtain a certain vacuum degree of work

this time depends on the pumping speed of vacuum system unit. Improve the pumping speed can shorten the time. Major studios is a clear need for large pump speed. Sometimes workshop is not big, but due to leaks and deflated, vacuum system also need larger extraction speed, otherwise a lot of leakage and deflated will greatly reduce the degree of vacuum, the system will not work.

3。 device or a suitable residual gas composition in the studio

the practice proved that only improve and guarantee the ultimate vacuum and vacuum degree of work is not enough, also need to have certain request for residual gas composition. For vacuum cameras, for example, to within a year of life to maintain sensitivity to reduce no more than a coincidence, device for oxygen content of residual gas in less than 10 - 2Pa。 High voltage vacuum switch tube should not contain hydrocarbon molecules, and so on. If there is no other source in the system, vacuum system of residual gas composition mainly depends on the characteristics of the pump.

4。 Vacuum system must also has a simple structure, reliable performance, convenient operation and maintenance, low cost, etc.

in order to meet these requirements, must be comprehensive consideration of pump selection, the determination of pipe size and layout and assembly process. These basic requirements are often interrelated. In vacuum system, for example, there is always a slight leakage, so high speed pump can get lower than the pump speed of vacuum pump is better work. Large water pump is expensive, however, consume large amounts of water and electricity, and so there is a reasonable choice. Mini vacuum pump is suitable for the instruments and small vacuum system. They are low cost, high efficiency and low noise. Some users are not suitable for larger industrial vacuum pump selection flow.

5。 Automation requirements

with the development of computer technology, user requirement for vacuum system automation has been improved. For vacuum system, automatic control is mainly to adjust vacuum pump flow rate and vacuum degree. Vacuum is usually by adjusting the vacuum pump, install throttle valve and pressure reducing valve to control the flow. Throttling can lead to great energy loss and additional noise. Best directly adjust the speed of vacuum pump. Industrial vacuum pump speed control method has a lot of kinds, mainly divided into two categories: the first is through the attachment to change the speed of vacuum water pump, such as the speed of the gear box; The second type is directly change the speed of the motor, such as thyristor cascade speed regulation, frequency control of motor speed, etc. Industrial vacuum pump is commonly used method is frequency control, energy saving effect is good, can realize stepless speed regulation, and speed than the big, speed control accuracy, speed and stability.

for mini vacuum pump is suitable for small vacuum system, mainly USES the decompression speed in the past. The side effects of decompression operation is to extend the service life of the water pump and motor. If the load of the pump is very big, very easy to cause the motor cannot be started after the decompression, resulting in a decline in motor temperature

in general, to have good air tightness of vacuum system, if there is no regular internal deflated and steam source, you can use smaller end have good vacuum pump. However, if the system leakage and deflated more, must adopt the method of improving pump speed to ensure system of vacuum degree. At this point, the pump speed should be adopted for large pump, and increase the conductivity pipe, as far as possible namely should choose short and thick pipe.