The Welch two-stage rotary vane pumps of the P - Z series are characterised by their high water vapour tolerance and reliability. Welch rotary vane pumps are designed to withstand large amounts of water vapour in the vacuum pump’s inlet vapour stream. This “water vapour tolerance” is the maximum inlet pressure point at which the pump is able to operate with pure water / fluids and at the same time prevents them of condensing inside the pump. Due to their low weight, high pumping speed and compact housing construction these pumps are ideally suited for use in laboratories for applications within rough and fine vacuum ranges from 1 to 10-3 mbar. It can also be used for Vacuum drying, Freeze drying, Schlenk lines and Backing turbomolecular pumps

• High water vapour tolerance for chemical applications
• Compact, robust and functional construction
• Low noise emission
• No oil contamination of the chamber by migration or suck-back
• High pumping speed
• Free of non-ferrous metals
• Low, ultimate pressures are reached quickly
• Long service intervals
• Low energy consumption
• Designed for permanent operation
• Rotary vanes made of a special plastic which are not affected by corrosion or damaged by dirt particles and have very good sliding properties