Edwards B777-51-000, Instruction Manual, Page: 10 / 40

B777-50-880 Issue D
Page 4 © Edwards Limited 2013. All rights reserved.
Edwards and the Edwards logo are trademarks of Edwards Limited.
Technical Data
2.2.1 Pumps without gas purge
The pumps are designed to pump the following residual gases normally used in high vacuum systems:

air

nitrogen

krypton

neon

hydrogen

propane

methane

carbon dioxide

carbon monoxide

helium

argon

ethane

butane
Use the pumps to pump oxygen and water vapour subject to the following conditions:

Oxygen
The oxygen concentration must be less than 20% by volume unless a bearing purge is applied as detailed in
Section 2.2.2 .

Water vapour
Ensure that vapour does not condense inside the pump – refer to Section 3.7.3 .
If pumping a gas not previously listed, contact the supplier for advice. If not, contact the supplier as the warranty
on the pump may be invalidated.
The pumps are not suitable for pumping aggressive or corrosive gases.
2.2.2 Pumps with gas purge
When purged with an inert gas the pumps can be used to pump oxygen in concentrations above 20% by volume.