The stator of a progressive cavity pump is mainly made of rubber. Because it needs to form a closed meshing cavity with the rotor, it is an interference fit with the rotor. When the rotor (main shaft) rotates and causes continuous friction, it will wear naturally.
Product Parameters
Product Name | Stator |
Material | NBR,HNBR,EPDM rubber,FKM,etc. |
What is a stator of a progressive cavity pump?
The stator of the progressive cavity pump is one of the essential main parts of the progressive cavity pump, also known as the progressive cavity pump bushing;
The material is usually divided into two categories:
1. Use inelastic hard materials such as metals, plastics, and ceramics;
2. Use rubber-like elastic materials (including a small amount of elastic-plastic).
At present, most stators of a progressive cavity pump are rubber-based stators;
The rotor, driven by the external power source, meshes with the stator to form a sealed cavity that separates the suction cavity and the discharge cavity so that the pump can work effectively.
Table A – Physical properties of rubber
Performance | Natural rubber (NR) | Nitrile rubber (NBR) | Chloroprene rubber (CR) | Butyl rubber (IIR) | EPDM | Chlorinated polyethylene (CSM) | Chlorohydrin glue (CHR) | Acrylic resin glue (ACM) | Chlorinated rubber (EPM) | Polyurethane rubber (Pu) |
---|---|---|---|---|---|---|---|---|---|---|
Vulcanized rubber hardness [Shore (A)] | 30 ~ 95 | 30 ~ 100 | 40 ~ 90 | 40 ~ 85 | 30 ~ 85 | 50 ~ 95 | 40 ~ 90 | 60 ~ 80 | 60 ~ 80 | > 30 |
Tensile strength /Mpa | < 18 | < 20 | < 20 | < 16 | < 20 | < 16 | < 18 | < 13 | < 12 | < 40 |
Operating temperature range /℃ | -55 ~ 100 | -30 ~ 120 | -20 ~ 120 | -40 ~ 150 | -50 ~ 150 | -30 ~ 125 | -40 ~ 150 | -20 ~ 200 | -20 ~ 250 | -20 ~ 80 |
Elongation | ● | ○ | ● | △ | ○ | ○ | ○ | △ | ○ | ● |
Elasticity | ● | ○ | ○ | × | ○ | △ | ○ | ○ | △ | ● |
Compression set resistance | ● | ● | ○ | △ | ○ | ○ | △ | ● | ● | ● |
Tear resistance | ● | ○ | ○ | ○ | ○ | ○ | ○ | ○ | ○ | ● |
Wear resistance | ● | ● | ○ | △ | ○ | ○ | ○ | ● | ● | ● |
Aging resistance | △ | ○ | ○ | ● | ● | ● | ● | ○ | ● | △ |
Flexibility | ● | ○ | ● | ● | ○ | ● | ○ | △ | ● | ● |
Heat resistance | △ | ○ | ○ | ● | ● | ○ | ● | ● | ● | △ |
Water resistance | ● | ○ | ● | ● | ● | ● | ● | × | ● | × |
Dynamic characteristics | ● | ○ | △ | × | ○ | △ | ○ | ○ | △ | ● |
Best performance | Good elasticity, high strength, good low temperature performance and optimal dynamic performance | Turbidity and heat resistance | Acid and alkali resistance, water resistance, ozone resistance, self extinguishing | Water resistance, steam resistance, good air tightness | Aging resistance, chemical resistance, insulation, temperature resistance | Aging resistance, ozone resistance, chemical resistance | Heat resistance, cold resistance, good solvent resistance | High temperature resistant oil, halogen resistant, heat resistant | High temperature resistance, excellent media resistance | Optimal wear resistance, high lightness, high elasticity |
Note: ●: Excellent performance ○: Good performance △: Poor performance ×: Very poor performance
Table B – Rubber’s media resistance table
Material | Maximum temperature | Suitable media | Unsuitable media |
---|---|---|---|
Natural rubber (NR) | 70 ℃ | The mixture of abrasive substances, a mixed liquid of organic matter, acid, alcohol, acetaldehyde, mud, cement slurry, cement | Ozone, concentrated acids, fats, oils, hydrocarbons (methane, ethylene, benzene) |
Nitrile rubber (NBR) | 90 ℃ | Hydrocarbons, weak acids, weak bases, light gasoline, mineral oils, animal and vegetable oils, fats, lubricants | Aromatic hydrocarbons (substances with benzene), chlorohydrocarbons, esters, acetaldehydes, ketones, ozone, strong acids |
Chloroprene rubber (CR) | 90 ℃ | Ozone, fat, paraffin-based lubricating oil, volatile lubricating oil, fatty hydrocarbon, reducing agent, salt solution | Strong acids, ketones, esters, aromatic hydrocarbons, chlorohydrocarbons, aromatic lubricants, acetic acid |
Fluorosulfonylated polyethylene glue | 110 ℃ | Alcohol, salt solution, ammonia, acid chemicals, oil, bleach, disinfectant, paper, mud, chromic acid | Strong acid, crude oil, tar, aromatic carbon compound, chlorohydrocarbon |
Fluororubber (EPM) | 180 ℃ | Aliphatic hydrocarbons, aromatic hydrocarbons, halogen hydrocarbons, oils, fats, acids | Ketones, esters |
Ethylene | 110 ℃ | Ozone, hot water, strong sulfuric acid, nitric acid, animal and vegetable oils, fats | Petroleum, solvent, benzene, aromatic hydrocarbon, light oil, tar |
Chloroprene rubber (VE) | 120 ℃ | Mineral oil (high temperature), animal and vegetable food oil, latex, rubber, paste-like solvent | Water, aromatic hydrocarbons, alcohol, ketones, alkalis, acids |
Sodium rubber | 80 ℃ | Sewage, abrasive material mixed liquid, acid sludge, ammonia, inorganic sewage mixed liquid | Same as natural rubber, other ketones and fats |
Butyl rubber (IIR) | 110 ℃ | Animal and vegetable oils, oils, fats, ozone, strong acidification drugs, acids, alkalis | Petroleum, solvents, benzene, aromatic hydrocarbons, light gasoline, lubricating oil |