1 / 19

Vacuum Pumps

Vacuum Pumps. Basics. vac·u·um noun 1. a space entirely devoid of matter.

danil
Download Presentation

Vacuum Pumps

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Vacuum Pumps

  2. Basics • vac·u·um • noun 1. a space entirely devoid of matter. • 2. an enclosed space from which matter, especially air, has been partially removed so that the matter or gas remaining in the space exerts less pressure than the atmosphere ( opposed to plenum). (dictionary.com) • Exhaust pressure= atm generally • Base pressure = pressure pump gets down to • Compression ratio = exhaust/base= big number • Boyles Law P1V1=P2V2

  3. History of vacuum pumps • Suction pumps go way back (Romans, Byzantine empire, etc) • Major improvements on the idea of vacuum made by Galileo, Evangeilist Torricelli, and Blaise Pascal • Otto von Guericke made first pump and famous for Magdeburg hemispheres experiment

  4. Types of Vacuum pumps • Positive displacement pumps • Expand a cavity, seal, exhaust, repeat • Momentum transfer pumps (molecular pumps) • High speed liquids or blades to knock gasses around • Entrapment • Create solids or adsorbed gases (cryopumps)

  5. Roughing pumps • Pumps from atm pressure down to rough vacuum (0.1 Pa, 1X10-3torr) • Necessary because turbo pumps have trouble starting from atmospheric pressure • Usually Rotary Vane pumps • Can have oil or not

  6. Rotary vane pumps Oil Sealed Rotary Pumps Understanding Gas Ballastwww2.avs.org/chapters/nccavs/pdf/Gas_Ballast_OilSealedPumps.pdf

  7. Rotary vane pumps Condensation of vapor in the gas mixture is a problem with these pumps. Solution Ballasting Works by increasing the gas/vapor ratio (air is mostly gas) As you might imagine this interferes with the final vacuum

  8. Types • One stage or two stage • Belt Drive or direct drive Slower 400-600 RPM Bigger, Cheaper Faster 1500 to 1725 RPM Smaller, lighter

  9. Turbo (molecular) pumps • Gas molecules interact with spinning blades and are preferentially forced downward • High vacuum (10-6 Pa) requires rotation of 20,000 to 90,000 revolutions per minute • Generally work between 10-3 and 10-7 Torr • Ineffective before gas is in “molecular flow”

  10. Turbo (molecular) pumps • Options: • Bearings: Ceramic (oil lubricated) Magnetic (supported w/out physical contact), also hybrid • Rotor options (Blade configuration) • Cooling (air or water)

  11. Pump Care • Rough pumps shouldn’t need a lot of maintenance • If they do repair kits are available: • Minor kit includes all necessary seals (shaft seals, valves, o-rings, etc) • Major kit includes Minor Kit components plus vanes, springs, plugs, etc. • Seem to be available for most major brands and types • Turbopumps should need even less maintenance, bearings can wear out but must be replaced by manufacturer for balancing. http://www.sisweb.com/vacuum/sis/iseries-maintkit.htm

  12. Pump specs Spec sheet for an Edwards A65209903 RV rotary vane pump $3171

  13. Subset of specs for Edwards EXT 556H turbomolecular pump

  14. Rotary Vane: Pump speed lower at low vacuum Turbo pumps: opposite Pump Speed Pressure

  15. Useful fitting terminology • Flanges • Standard quick Release (QF, KF, NW, or DN) • Named based on internal diameter DN16KF is 16mm (16-50mm) • Large Quick releases (LF, LFB, MF or ISO) • Clamps or bolts (63-500mm) • Conflat (CF) used in ultra high vacuum settings, usually metal to metal seals • Sizing odd: Europe inner diamter in mm, NA outer diameter in inches

  16. Sizes we will likely find. www.vacuumresearchcorp.com/pdfs/valves/nwflanges06.pdf

  17. Pumps on the Delta S • Pumping system for Analyzer • Turbo molecular pump TPH 050 • Vacuum pump E2 M1, 52 • Differential Pumping system • Turbo molecular pump TPH 050 • Turbo molecular pump TPH 240 • Vorvakuumpumpe E2 M5, 50160 Hz

  18. Turbo molecular pump TPH 050 Turbo molecular pump TPH 240

  19. Units of pressure for your notes

More Related