Roots blowers

Reliable pumping for large volumes

Leybold RUVAC roots blowers are used in combination with backing pumps to achieve lower pressures, higher pumping speeds and used when larger capacities are required. Classic roots blowers are equipped with a pressure switch for protection against thermal overload, while roots blowers operated by frequency converters or with internal bypass lines can run continuously.

In combination with backing pumps, which compress against the atmosphere, these pumps can improve the attainable ultimate pressure of a pump system by a factor of 10. With two Roots vacuum pump stages and a corresponding backing pump it is possible to attain pressures in...

Classic Leybold roots blower

Classic roots blowers, WA & WS series, are equipped with simple flange-mounted or integrated motors that are directly supplied with mains voltage and run at a constant speed. Since the motor load increases with rising suction pressure, these roots pumps may be cut in below a certain pressure only. Therefore, this type is only suitable for very long pumping cycles or for stationary operation at low pressure. For fast, cyclical pumping, switching the roots stage on and off constantly is not practicable. In order to protect the roots pump reliably a pressure gauge monitoring the pump’s cut-in point is always required. There are several principles available to seal the drive shaft under vacuum against atmospheric pressure.

With the three different series WA, WS and WH, Leybold offers a range of solutions for different industrial applications.

RUVAC WA / WAU series

The RUVAC WA / WAU roots blowers are equipped with a flange-mounted motor. The drive shaft is fed through shaft seals to the outside. This allows simple and cost-effective standard motors to be flange-mounted.

RUVAC WS / WSU series

The RUVAC WS / WSU roots blowers are equipped with a canned motor. The motor rotor and stator are separated by a thin-walled cartridge for an absolute hermetically sealed pump important for pumping aggressive or toxic media. Motors of the WS series are available both water-cooled and air-cooled. As there are no shaft seal rings, the WS pump is easier to maintain.

RUVAC WH / WHU series

The RUVAC WH / WHU roots blowers are equipped with a hermetically sealed motor. WH pumps are airtight and suitable for pumping toxic gases, which must not be discharged into the environment. Unlike canned motor pumps, WH pumps feature a plastic encapsulation of the entire motor stator, separating it from the motor rotor that runs in a vacuum. By removing the metallic can and applying smaller gaps, this technology achieves higher efficiencies. The WH series features integrated water cooling and is particularly energy efficient.

Roots pumps with frequency converter

Leybold roots blowers are available with integrated frequency converters and can also be operated with external converters.

An elegant and energy efficient solution to protect roots blowers from overload is the use of frequency converters. These converters adapt the pump's motor speed to the load and enable safe operation...