Rotary lobe blowers are static compression systems, whilst booster vacuum pumps are for use as stand-alone units or to form a pump set in combination with other pumps.

Three-Lobed Rotary Blowers

	Suitable for pressure or vacuum operation
	0.5 bar (abs) vacuum operation and 2 bar (abs) pressure
	Capacities of 15 to 8,300 m³/hr

Booster Vacuum Pumps

	3-stage model gives maximum vacuum of 0.5 mbar (abs)
	3-stage model is suitable as a stand-alone unit or as part of pump set
	Single-stage models designed for vacuum pump sets in conjunction with a rotary vane backing vacuum pump
	Pump set can achieve 500 to 4,000 m³/hr at an ultimate vacuum of 0.01 mbar (abs)

Technical Overview
Similar to the rotary vane pumps, the rotary lobe blowers are also static compression systems, although the compression does not result from an internal volume reduction.

Because of the non-contact operation of the rotary lobe blower, there is no possibility of contamination of the pumped gas.

The three-lobed rotary blower SHARK is for vacuum operation to 0.5 bar (abs.) and pressure operation to 2 bar (abs.) at capacities of 15 to 8300 m3/hr.

The single stage booster vacuum pumps VWP and WKP from Rietschle are designed for use in pump sets in combination with a rotary vane backing vacuum pump. The conveyed air is not discharged to atmosphere but piped into the inlet port of the connected high pressure stage (rotary vane pump). The achievable capacities range from 500 to 4000 m³/hr at an ultimate vacuum of 0.01 mbar (abs.).

The Rotary Lobe Principle
Similar to the rotary vane pump, air enters the inlet opening (1) into a conveying cell formed by the two rolling pistons (2) + (3) in the housing. This is until the cell is separated from the inlet by the following piston head (5). The air in the cell (4) is conveyed without reduction until it reaches the outlet (6), there air with a higher absolute pressure flows from the pressure chamber into the following cell, and must then be discharged. It is during this stage of the conveying that external compression takes place.