There are many types of vacuum pumps, and the conditions and application fields are complex. Therefore, there are many factors involved in the selection of vacuum pumps. Dry screw vacuum pump manufacturers talk with you about the six basic considerations that need attention.
1. In the vacuum pump selection, the determined product needs to be able to smoothly withdraw various gases released during the process.
In the vacuum pump application process, the gas medium is diverse, flammable, explosive, easy to condense, and easy to reverse, etc. The vacuum pump used must ensure applicability. For example, a large amount of water vapor will be generated in the process, and the vacuum pump used must be suitable for pumping steam. The oil seal mechanical pump is obviously not suitable.
Second, the ultimate vacuum of the vacuum pump must be higher than the vacuum required by the process, at least one order of magnitude higher, and the equipment is suitable to work within the required working vacuum range.
The ultimate vacuum of a vacuum pump is the degree of vacuum that can be achieved when the pumping speed is zero. Therefore, in order to ensure the pumping speed of the vacuum pump within the working vacuum degree, it is necessary to satisfy that the ultimate vacuum degree is greater than the working vacuum degree, and a relatively large pumping speed is required in the interval.
Third, the pumping speed of the vacuum pump is greater than the maximum amount of bleed air in the process.
In order to ensure the degree of vacuum, vacuum pump selection involves the continuous deflation during the process, and the pumping speed of the vacuum pump or vacuum system must meet the maximum air bleed in the process. If there is a cold trap or baffle in the system, the effective pumping speed after adding the trap or baffle should be greater than the maximum bleed air volume during the process. If a sudden large amount of deflation occurs in the process, the effective pumping speed of the system should be increased appropriately, usually increasing to 2-3 times of the maximum bleed air.
4. In the vacuum pump selection, the selected vacuum pump must meet the process requirements for its working medium and manufacturing materials.
Vacuum pump applications, especially in the fields of pharmaceuticals and chemical engineering, are often characterized by corrosive gases. Therefore, the equipment must have corresponding anti-corrosion measures. If the acid-alkali gas needs to have a corresponding anti-corrosion coating; when dust or particle-containing gas is added, the dust is added to the pump inlet, the filter or the pump itself is resistant to it, and the like.
Fifth, in the continuous production process, the selected vacuum pump must meet the needs of continuous production. If necessary, set an automatically replaced spare vacuum pump to reduce accidental production interruptions. If the amount of air released during the process is getting smaller and smaller, you can set the maintenance pump to achieve energy saving.
Sixth, the economical use of vacuum pumps.
In the vacuum pump selection process, when a variety of vacuum pumps can meet the process requirements at the same time, it is necessary to carry out economic analysis of costs and operating costs, and use vacuum pumps with good economy, reliable operation, small maintenance, and convenient use and maintenance.