Dry multi-stage Roots technology, SD versions, ACP pumps with a Pumping speed of max. 40 m3/h No particle contamination, thanks to frictionless design: no wearing parts in the pumped gases path No hydrocarbon vapors backstreaming: ACP series pumps are free of lubricant inside the pumping module Constant performances (Pumping speed, max. and ultimate pressure) High reliability : thanks to our expertise of dry multi-stage Roots pumps since 1988 Low maintenance costs: no annual field service, complete overhaul only every 22000 hours for ACP 28/40 Condensable vapor ability: with gas ballast ports and drainable silencer. ACP series pumps can handle up to 1000 g/h of pure water vapor.