Roots Pumping Stations

Roots pumping stations are the best solution for many industrial applications because they are robust and durable. They are reliable, require little maintenance, and can be configured to suit many process requirements.

The appropriate pump principle in addition to the Roots

Roots pumping stations are the powerhouses among backing pumps: They offer a high pumping speed, especially in the transition range between rough and fine vacuum, i.e. in the range from atmosphere to around 10-3 hPa. The CombiLine product range includes various pumping technologies combined with at least one Roots pump. Our decades of experience in pumping station construction flow into this standardized series. If required, these pumping stations can be supplied with a magnetic coupling and are therefore hermetically sealed. These require little maintenance, and are suitable for use in potentially explosive environments or for evacuating explosive gases (ATEX).

Roots pumps (named after the inventors Francis and Philander Roots, who tested them in practice for the first time) are basically dry, i.e. oil-free, pumps that do not require any operating fluid in the work area. Except for gas circulation-cooled Roots pumps, which can compress against atmosphere, this type of pump requires a backing pump that reduces the pressure down to the working pressure of the Roots. Depending on whether the backing pump is dry or oil-sealed, the entire pumping station is also considered dry or oil-sealed.

Brochure: CombiLine Roots pumping stations

Dry (oil-free) Roots pumping stations

For a dry pumping station, a dry backing pump is combined with the Roots pump. A screw pump from the HeptaDry series is usually used for this. Together with the new generation of HiLobe Roots pumps, it ensures a high pumping speed and, as a result, quick evacuation times. Alternatively, a conventional OktaLine Roots pump can be used.

Dry Roots pumping stationsarrow_forward

Oil-lubricated Roots pumping stations

The combination of an oil-lubricated rotary vane pump with a Roots pump is the classic solution for low final pressures with high pumping speeds. Two different versions are used: With a single-stage backing pump HenaLine or UnoLine Plus, or with a two-stage DuoLine pump. The use of oil-sealed backing pumps is still the preferred solution for various industrial processes as it is the most robust and cheapest solution in terms of both acquisition and service life costs.

Oil-lubricated Roots pumping stationsarrow_forward

Pumping stations with HiLobe Roots pumps

Features of pumping stations with frequency-controlled HiLobe Roots pumps

  • Assembled and piped together

  • Particularly suitable as a pre-pumping station for high vacuum pumps

  • Increased safety: Intelligent interface technology allows process monitoring (Industry 4.0)

  • Efficient: Shortest pump-out times thanks to the superior next-generation drive concept

  • Low operating costs: State-of-the-art motor technology (IE4 standard) and air cooling (up to +40 °C)

  • As an option, each pumping station is also available with a control cabinet and control, as well as with a ProfiNet interface

  • Thanks to the unique magnetic coupling of the DuoLine in combination with the hermetically sealed HiLobe series, permanently sealed pumping units are available, for example to pump valuable noble gases.

HiLobe and dry screw pump

  • Backing pump: HeptaDry

  • Pumping speed backing pump: 110 to 950 m3/h

  • Pumping speed pumping station: 959 - 5,098 m3/h (higher on request)

  • Final pressure: Up to 5 · 10-3 mbar

  • Suitable for quick evacuation of chambers and load lock applications

CombiLine RHarrow_forward

HiLobe and single-stage rotary vane pump

  • Backing pump: HenaLine or UnoLine Plus

  • Pumping speed backing pump: 25 - 760 m3/h

  • Pumping speed pumping station: 1,028 - 4,689 m3/h (higher on request)

  • Final pressure: Up to 2 · 10-2 mbar

  • Solid pumping station with gas-independent pumping speed and long service life

CombiLine RUarrow_forward

HiLobe and two-stage rotary vane pump

  • Backing pump: DuoLine

  • Pumping speed backing pump: 300 m3/h

  • Pumping speed pumping station: 975 - 2,037 m3/h (higher on request)

  • Final pressure: Up to 1 · 10-3 mbar

  • Suitable for achieving low final pressures

CombiLine RD (+ RS)arrow_forward

In addition to pumping station combinations with the HiLobe, Roots pumping stations based on conventional Roots pumps are also available, especially for lower pumping speeds (and customer-specific Roots pumping stations for special requirements). Instead of the HiLobe, a pump from the OktaLine is used.

Pumping stations with OktaLine Roots pumps

Features of pumping stations with conventional OktaLine Roots pumps

  • Assembled and piped together on a sturdy common frame

  • Each pumping station is also optionally available with a control cabinet and PLC

  • All motors comply with efficiency class IE3

  • Thanks to the unique magnetic couplings of the OktaLine and DuoLine, permanently sealed pumping stations are available, for example to pump valuable noble gases

OktaLine and dry screw pump

  • Backing pump: HeptaDry

  • Pumping speed backing pump: 110 to 320 m3/h

  • Pumping speed pumping station: 450 - 1,800 m3/h (higher on request)

  • Final pressure: Up to 2 · 10-3 mbar

  • These pumping stations have an oil-free backing pump, so they are dry. This means that media that would react with pump oil can be pumped, and no pump oil is carried into the process. As a result, they have a high degree of compatibility with various processes.

CombiLine WHarrow_forward

OktaLine and single-stage rotary vane pump

  • Backing pump: HenaLine or UnoLine Plus

  • Pumping speed backing pump: 25 - 760 m3/h

  • Pumping speed pumping station: 230 - 1,900 m3/h at 50 Hz, 280 - 2,200 m3/h at 60 Hz (higher on request)

  • Final pressure: Up to 2 · 10-2 mbar

  • Quick evacuation of (lock) chambers

CombiLine WUarrow_forward

OktaLine and two-stage rotary vane pump

  • Backing pump: DuoLine

  • Pumping speed backing pump: 300 m3/h

  • Pumping speed pumping station: 220 - 1,800 m3/h at 50 Hz, 260 - 2,160 m3/h at 60 Hz (higher on request)

  • Final pressure: Up to 5 · 10-4 mbar

  • Classic pre-pumping station for high vacuum pumps, used for coating and in metallurgy

CombiLine WD (+ WS)arrow_forward

Competent advice for your decision

At Pfeiffer Vacuum, experts with many years and decades of experience in the use of vacuum in various industries work. They will be happy to accompany you on the way to selecting the right pump solutions and beyond. In addition to the design and construction, manufacturing and assembly, Pfeiffer Vacuum also offers a global service for the maintenance of pumps and accessories. Do you need to talk? Your contact person will be happy to inform you about our entire range of services beyond product advice.

Pumping station control and accessories for Roots pumping stations

Although CombiLine pumping stations are basically standardized, they can still be configured to suit the application: For example, the electronics for a HiLobe can be mounted either in a separate small cabinet on the frame or on mounting plates that can be integrated into a larger cabinet. Depending on weight and accessibility, pumping stations can be supplied on adjustable feet or castors. And, of course, all the accessories available for the individual pumps will fit, even when the pumps are installed in a network to form a Roots pumping station.

Details about the pumping station control can be found in the CombiLine brochure and also in the operating instructions. A little tip: An OmniControl mobile device with a large 3.5" touch display is very practical and intuitive to use for commissioning and generally reading out error codes.

You will find suitable accessories among the products in the shop, or on request we will recommend them according to your application.

  • Oil sump

  • Swivel castors / machine feet

  • Color variants

  • Valve in front of the pumping station

  • Measuring device in before the pumping station

  • Measuring device between the pump stages

  • Electric cabinet with control

  • ProfiNet interface

  • Spraying lance

  • Barrier gas

  • Oil filter (mechanical / chemical)

  • and much more

OmniControl mobile device

Do you already know our Vacuum Calculator?

Do you operate a CombiLine Roots pumping station and would like to know which alternative pumps or pump combinations can be used for a comparable evacuation performance? Either you contact your contact person or you can try out our Vacuum Calculator: It can not only make new designs but also guides you through the comparison step by step; a pre-selection of the well-known CombiLine pumping station makes data entry easier. In addition to the suitable products, you can view curves and get an initial cost indication. You can also send the information you have entered directly to us as an inquiry. We will then look at your entries in detail and contact you personally.

FAQ (frequently asked questions)