ACP 40- Standard version (SD version)_PFEIFFER VACUUM Dry, compact multi-stage Roots pumps with a pumping speed of max, 37 m3/h * Due to frictionless design, no contamination due to particles: no wearing parts in the path of gas flow * No hydrocarbon vapor backstreaming: pumps in the ACP series are lubricant-free in the pumping module * Constant performance (pumping speed, maximum continuous inlet pressure and ultimate pressure) * High reliability: thanks to extensive experience with dry Roots pumps since 1988 * Low maintenance costs: no annual service, complete overhaul only every 22,000 hours for the ACP 28/40 * Suitable for condensable vapors: with gas ballast and drainable silencers.