Main pageRotor and Stator (Screw Pumps)

Rotor and Stator (Screw Pumps)

1. What are rotor stator pumps and how do they work? 

Rotor Stator pumps are progressive cavity pumps - a type of positive displacement pump. They are used for pumping screed, mortar, grout, plaster, and cement.

The fixed stator and the rotating component, the rotor, are the yin and yang of progressive cavity pumps. The rotor is the spiral steel shaft that creates conveying chambers of the inner outline of the rubber tube. Stators are metal tubes with internally molded cavities made of synthetic or natural rubber.

When the rotor is triggered, the conveying chambers move in the direction of flow. This is how the constant flow of material is actually achieved. The rotor takes a form which resembles a corkscrew, which combined with the off-center rotary motion, gave its alternative name: eccentric screw pump.

We produced a short animated video to show you the inner workings of progressive cavity pumps:

2. What are rotor stator pumps used for?

Our customers primarily use rotor stators in constructions, to pump grout, screed, mortar, plaster, or refractory tundish. But rotor stators are also commonly used in food, pharmaceutical, and cosmetics industries for processing of colloidal liquid and liquid systems, as well as to disperse or break solid particles and aggregates. Rotor stators also cater to wood processing and cellulose production, to the chemical industry, to the petroleum industry, to domestic and industrial sewage, as well as to low flow, high head, agricultural water pumping.


3. What are the relevant factors when choosing the rotor stator?

Size, diameter, grain of material, and the flow rate you want to achieve

You will want to choose your rotor stator based on its size and diameter, but also depending on the grain of your material, and your desired flow rate. Different rotor stator pumps suit different materials and purposes, and achieve different pumping results. Different flow rates and pressure stabilities are achieved by varying designs of screw pumps.


4. Maintenance-free, or clampable rotor stators?

Maintenance-free stators are more user friendly. They can be used directly after being installed in the machine. They have unslotted steel tubes as outer casings. This means they allow for constant delivery pressure and support a hassle-free process. 

Clampable stators are clamped according to material and grain size. They come in two types: stators with built-in tensioning clamps, and slotted stators, that are provided with an external tensioning strip. 

Both transport a diversity of materials, smoothly, continuously and with minimum pulsation. Pumps which require clamping have an integrated clamping bar, or a grooved stator for the clamp, with or without an additional separate clamp. When the delivery pressure drops, the stators must be retightened. 


5. How to choose the right shore for your rotor stator?

The shore deals with different rubber qualities and different hardnesses. 

The shore is very significant: the smaller the number of the shore, the harder is the rubber. A greater shore means the material is relatively soft. If you require a harder rubber, you want to opt for a smaller shore. But some materials work better with a softer rubber. Harder materials with pointy aggregate may damage the rubber. 

When choosing your optimal shore, you want to consider your working temperature and climate, as rubber softens in heat. Our customers in warmer climes prefer a stator with harder rubber. Similarly, customers based in temperate regions alternate shores based on seasonal weather shifts. 

6. Does Putzparts supply high quality rotor stator pumps?

Putzparts rotor stators are made in Germany. Our high alloyed steel rotors are never hollow. We use precisely drilled, high quality steel for long lasting rotors. In our stators, we use high endurance rubber, which makes them  long-lasting, reliable, and supportive of a solid, consistent pumping experience. 

7. Can I use the pumps for different machines?

We provide Rotor Stator Pumps for a variety of different machines by Putzmeister, PFT, M-Tec, Uelzener, Turbosol, Mai, Utiform, Inotec, Imer, Brinkmann and many more. Many machines use the same rotor stator types. 

For plaster, the most popular pump is the D6-3, which has a solid output of 30 litres per min at 400 rpm. If you need more, you can go with the D8-2, which at 66 litres per minute has more output than any other D-pump.

For floor screed conveyors like the Putzmeister S5, we recommend the 2L6 or 2L88. These pumps come in different versions. You can opt for either maintenance free or clampable stators, so you can use an external clamp.

8. I can’t find the rotor stator I’m looking for. Can you supply different types?

Most likely, yes. We supply a robust selection of rotor stator pumps in our shop, and additionally provide custom series of nearly any stator size at optimal costs for you.

If you can’t find what you’re looking for, or need help in choosing what’s best for you, please contact us. 

We react promptly to customer queries and will provide you with the required facilities for your specific purpose.

Show 61 to 67 (of in total 67 products)

D5-2,5 Stator

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D5-2,5 Rotor

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Rotor D8-2

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Stator D8-2

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PFT Twister Stator D6-3

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rotor D6-3

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D6-3 Stator

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Show 61 to 67 (of in total 67 products)