Vacuum technology takes a different kind of thinking -- almost an upside-down kind of thinking -- since it means dealing with negative pressure. Some common terms can cause confusion because of conflicting definitions in the industry. For instance, high vacuum is a lower pressure than low vacuum. An easy way to understand this is to remember that the starting point for positive and negative (vacuum) pressure is atmospheric pressure (1x105 or 100000 Pascal). The further away from atmospheric pressure you go in either direction (up or down), the higher the positive pressure (up) or the higher the negative pressure ((vaccuum (down)). Here is a chart that explains the different terms that are used to describe different levels of vacuum.
| Pascal (Scientific Notations) | Pascal | Degree of Vacuum |
| 1x105 to 3x103 | 100000 to 3000 | Low Vacuum |
| 3x103 to 1x10-1 | 3000 to 0.1 | Medium Vacuum |
| 1x10-1 to 1x10-4 | 0.1 tp 0.001 | High Vacuum |
| 1x10-4 to 1x10-7 | 0.0001 t0 0.0000001 | Very High Vacuum |
| 1x10-7 to 1x10-10 | 0.0000001 to 0.0000000001 | Ultra-High Vacuum (UHV) |
| <1x10-10 | <0.0000000001 | Extremely-Ultrahigh Vacuum (EHV or XHV) |
Vacuum has become such an essential part of many industries that there are trade shows dedicated to showcasing equipment used in vacuum systems. Some of that will be on display in San Jose on Feb. 20 at the 35th Annual Vacuum Equipment Exhibition. Admission is free, and if you show up at 11am for the start of the exhibit, you can have a complimentary lunch. We'll be happy to talk to you about how we can help with any of your vacuum and fluid system needs. The exhibit will be at the Holiday Inn San Jose Airport, 1350 N. First St., from 11am to 7 p.m.
But if you can't make it to San Jose that day, you can still download information and specifications on vacuum tubing products, our Ultra-Torr vacuum fittings, and other fittings Swagelok manufactures that are used in vacuum systems. The Swagelok Ultra-Torr Vacuum fitting employs an o-ring seal that can be used on glass, metal or plastic tubing. Seal performance is maintained through repeated disconnects, and it has a knurled nut for easy finger tight assembly. The Ultra-Torr fitting design has been helium leak tested to a maximum leak reate of 4x10-9 std cm3/s at ambient temperature.
Note: This exhibit is also a good opportunity to get a demonstration of our Electronic Desktop Reference. The eDTR puts Swagelok catalogs, technical bulletins, installation instructions, videos, archives and more on a flash drive no bigger than your finger. You'll see in person how much easier it is to use than fumbling through multiple catalogs or binders to find what you need.
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