The Edwards 18B4B vapour booster pumps offer higher pumping speeds, of up to 6000 l s-1 at pressures intermediate between mechanical boosters and diffusion pumps. Vapor boosters from Edwards have been proven in the field for over 30 years. With a constant program of updates and modernization, with input from OEM’s and end users, combined with inherent reliability, ease of use and tolerance to various inlet and exhaust pressures they have been used extensively in metallurgy and coating industries as well as other specialist applications.
Vapour booster pumps operate in a similar way to vapour diffusion pumps but, in addition to having annular jets, they have an ejector stage which greatly boosts the throughput of the pump. The ultimate pressure of these pumps is around 10-4 to 10-5 mbar above which the pumps exhibit considerable pumping speed for permanent gases. High critical backing pressures allow the use of relatively small mechanical backing pumps. The pumps are used in the 10-1 to 10-4 mbar range where rotary pumps are at their limit and ordinary diffusion pumps exhibit instability.
These pumps are most useful in pumping contaminated systems and high loads of hydrogen, hence their use in metallurgical and chemical processes.
- Vacuum metallurgy
- Distillation, drying and degassing
- Thin film coating and metallizing
- Large-scale research