Technology
Claw pressure/vacuum pumps
Vacuum and compressed air from one claw stage – dry, contact-free and air-cooled. 2 current models from Elmo Rietschle – comparable by flow rate and rated motor power.
Compare 2 modelsHow the technology works
- 2models
- 1series
- 1manufacturer
- 117.8 m³/hhighest pumping speed (50 Hz)
Touch the points: the parts explain themselves.
Manufacturers and series
Manufacturer and series
Each series leads to its page with all models.
Elmo Rietschle
2 models · 94–117.8 m³/h
Product overview
Compare the models
The filters on the left narrow down the selection by the key figures of the models – for 50 or 60 Hz.
No model matches these filters.
C-KLR series 2 models
Models that a manufacturer no longer carries in its current range are not part of this overview; they are listed in its “Outdated models” section – for example under outdated Busch models.
Operating principle
How a claw pressure/vacuum pump works
In the housing, two claw rotors turn in opposite directions – without contact and with very narrow gaps; a precision gearbox synchronises them. When the claw moves past the inlet connection, the air is drawn in, transported to the pressure side and compressed there between the rotors. In this way a single claw stage delivers vacuum and compressed air at the same time.
The drawing shows the basic principle of the claw pump in simplified form. In many designs the ports are at the side and are uncovered by the rotors.
- SuctionWhen the claw moves past the inlet connection (A), the air is drawn into the suction chamber (D) – this is the side on which the vacuum is created.
- CompressionThe rotors (C) carry the air to the pressure side; there the volume between them decreases (E).
- DischargeAs soon as the rotor uncovers the discharge channel, the compressed air leaves the pump through the outlet connection (F).
Key figures
The technology in figures
The ranges result from the current models in our range.
Pumping speed (50 Hz)
94 to 117.8 m³/hin our range
Rated motor power (50 Hz)
4 to 5.5 kWin our range
Vacuum and overpressure instead of ultimate pressure
Pressure/vacuum pumps suck and blow at the same time. The manufacturer therefore states the vacuum and the overpressure in combined operation. Both values are given in the technical data of the models.
What characterises the technology
One stage, two tasks
Pressure and vacuum are generated in a single claw stage.
Dry and contact-free
The claw rotors run against each other dry and without contact; the narrow gaps provide the seal.
Timing gear
A pair of gearwheels in the gearbox synchronises the two rotors. There is oil only there.
Air cooling
The cooling is built in; additional cooling media are not needed.
Advantages
What speaks for this technology
- Vacuum and compressed air from one machine
- Oil-free compression
- Rotors run without contact
- Built-in air cooling
- Low operating costs
Applications
Where they work
- Vacuum and compressed air at oncefor machines and systems that need both at the same time
- One machine instead of twoin place of a separate vacuum pump and a separate compressor
Frequently asked questions
Questions about claw pressure/vacuum pumps
How does a claw pressure/vacuum pump work?
Two claw rotors turn in opposite directions and without contact in the housing. They draw in the air on one side, compress it between them and expel it on the other side as compressed air. The drawing in the section Operating principle shows the basic principle.
How does it differ from a claw vacuum pump?
A claw vacuum pump delivers vacuum only. The pressure/vacuum pump additionally provides compressed air with the same claw stage.
Why is no ultimate pressure given here?
Because the pumps suck and blow at the same time: the manufacturer states the vacuum and the overpressure in combined operation. Both values are given in the technical data of each model.
From which manufacturers does Ehrler & Beck carry this technology?
Currently from Elmo Rietschle. The series are listed in the section Manufacturers and series.
How do I find the right model?
In the product overview, the filters narrow down the selection by the key figures of the models. For sizing, it is best to tell us the gas to be conveyed, the working pressure and the flow rate you need – we will be glad to advise you.
What do the figures for 50 Hz and 60 Hz mean?
Flow rate and rated motor power depend on the mains frequency. The overview therefore shows both values wherever the manufacturer states them, and the size filters can be switched between 50 Hz and 60 Hz.
Does Ehrler & Beck also supply spare parts and service?
Yes. Ehrler & Beck offers original spare parts and accessories as well as maintenance and repair.
Which model fits your process?
Tell us the gas to be conveyed, the working pressure and the flow rate you need – we will advise you on selection, spare parts and service.
