Rotor pumps are rotary displacement pumps, often used to transport high viscosity liquids or multiphase fluids, and their performance, design, and operation are closely related to the medium being transported. The nature of the flow of the medium determines the design requirements for the pump. Pump in the transport of high viscosity liquids, requiring reliable work, stable performance, good suction performance, can not break the flow. Pump transport medium usually have a certain chemical corrosion, some media also belong to the solid state at room temperature, pumping state is in excess of its melting point temperature of the liquid state, the pump and there are formed by the relative movement of the gap, in order to maintain efficient operation of the pump, and to extend the service life, the material of the pump overflow parts need to be high temperature, corrosion resistance, wear resistance. The structure of the pump should be as simple as possible to facilitate disassembly, cleaning and maintenance.
The unique characteristics of the rotor pump due to its working principle and structure are characterized by the following features:
1. From a few hundred centipoise to hundreds of thousands of centipoise, from low viscosity to semi-solid state fluid.
2. Large over-flow area in the pump, smooth over-flow, and its flow rate is not easy to make the medium break the emulsion in the process of conveying.
3. The suction resistance in the pump is small, and the rotor pump has the ability of self-priming.
4. The rotor pump has no internal compression process. Inside the rotor pump, the liquid pressure is not increased due to volume reduction, but the higher pressure at the outlet makes the liquid flow back to increase the liquid pressure in the pump volume, which is called equal volume compression. Therefore, it is more than the internal compression to consume compression work, the efficiency is usually lower than the various pumps with internal compression. This is its main disadvantage.
5. Since there is actually some clearance between the rotors and between the rotors and the casing, there is no other frictional movement in the rotor pump except for the bearings and timing gears, which makes this model have the advantages of a small base, no vibration, long life, and high mechanical efficiency. At the same time, there is no need to lubricate the rotor and pump body, so that the transported medium does not contain oil. Of course, it is the presence of gaps between the rotors and between the rotor and the casing that causes liquid leakage, thus affecting the development of high pressure and high efficiency of the rotor pump.
6. The medium containing gas can be transported. After special improvement of the leaf type, such as hanging rubber coating on the lobe surface, can also convey the media with fine particles.
7. The efficiency is about 70%, and the high efficiency area is wide.
8. Reliable performance, simple and compact structure, good self-priming, light weight, small volume, easy maintenance and cleaning.
9. With metering function, it has the same positive displacement characteristic as reciprocating pump, and can be used in metering occasions.