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 can be used for pumping various viscous and abrasive fluids.
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 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?
Various industries use progressive cavity pumps. Putzparts is specialised in rotor stators for the construction and refractory industry to pump screed, mortar, grout, gypcrete, plaster and fireproofing cement.
Rotor stators also cater to wood processing and cellulose production, the chemical industry, the petroleum industry, domestic and industrial sewage, and low flow, high head, and agricultural water pumping.
3. What are the relevant factors when choosing the rotor stator?
Size, diameter, grain of the material, and the flow rate you want to achieve
You will want to choose your rotor stator based on its size and diameter, depending on the grain of your material and your desired flow rate. Different rotor stator pumps to 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 diverse 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 is very significant: the smaller the number of the shore, the softer is the rubber. We recommend a soft rubber if you pump material with sharp aggregates, as they wear out less quickly.
A harder rubber generates more pressure. S
When choosing your optimal shore, consider your working temperature and climate, as rubber softens in heat. Our customers in warmer climates prefer a stator with harder rubber. Similarly, customers 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.
Our stators 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 various 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 has more output at 66 litres per minute 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 to 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 choosing what’s best for you, don't hesitate to contact us.
We react promptly to customer queries and will provide the required facilities for your specific purpose.