R&D Success - The Importance Of Working In A Vacuum

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Ultra-high vacuum technology is used to create enclosed environments where the air pressure contained within the contained space is well below atmospheric pressure. Such environments play a vital role in research and development, scientific experimentation, and space exploration. Understanding the basic principles of vacuum technology is essential to sourcing the right equipment.

Air is a mixture of gases that has approximately 1025 particles per m3 of air when measured at one bar of air pressure. Particles exert force, or pressure, on the walls of any defined space. The fewer the particles there are present in that space, the lower the force that is exerted on the walls of the given space. An absolute vacuum would have no particles present, and therefore no pressure would be exerted. In a controlled vacuum environment, pumps are used to remove as many particles as possible to create an ultra-high vacuum environment. The more particles that are removed, the closer to an absolute vacuum the environment becomes. Where fewer particles are removed from a chamber, the environment created is termed a rough vacuum. 

One of the problems for businesses when it comes to UHV creation is altitude. As this increases the external air pressure falls. This affects a researcher’s ability to create vacuum conditions and reduces the attainable vacuum level of an ejector. Vacuum ejectors function according to the venture principle, and are much simpler in design than other vacuum generators. Other ultra-high vacuum parts used to create vacuums include the displacement pump. This works by having air flowing into a space, which is then mechanically shut off, compressed, and then ejected.

Why quality valves are important

UHV gate valve components are extremely important to any vacuum system. You can find more information here about valves. The main reason for this is that they enable the isolation of specific regions of the vacuum system. This may need to occur for maintenance, processing, and pumping down. Gate valves are just one type of valve that is important to vacuum systems.

There are two main design types for valves used within a UHV system. Firstly, the right-angled valve; so named because of the position of the vacuum tube connections. The second is the straight-through valve. The most common form of straight-through valve is the gate valve. One of the reasons for its popularity is because it facilitates in providing large unimpeded conductance. These ultra-high vacuum parts need to have a minimum leak rate in their closed position and provide maximum conductance when open. 

Additionally, it is important that they are not a source of contamination. To ensure this there are limited materials that can be used in their construction. They must have negligible gas permeability and be able to be outgassed through baking at temperatures of at least 200 C. These requirements are the main reason why the seals used in gate valves resemble the same configuration as those used in flange seals. The operational element of the valve requires similar specifications as mechanical feedthroughs used in other areas of the vacuum system. However, in terms of right-angled valves, used in relatively small-bore tubing, the O-ring seal is more likely to be applied without affecting the system’s ability to reach ultra-high vacuum levels.

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