Three commonly used sealing materials for solenoid valves
- 2021-10-12-
1. NBR nitrile rubber
The solenoid valve is made by emulsion polymerization of butadiene and acrylonitrile. Nitrile rubber is mainly produced by low-temperature emulsion polymerization. It has excellent oil resistance, high wear resistance, good heat resistance, and strong adhesion. Its disadvantages are poor low temperature resistance, poor ozone resistance, poor electrical properties, and slightly lower elasticity. The main purpose of solenoid valve: solenoid valve nitrile rubber is mainly used to make oil-resistant products. Solenoid valves such as oil-resistant pipes, tapes, rubber diaphragms and large oil sacs are commonly used to make various oil-resistant molded products, such as O-rings, oil seals, and leather. Bowls, diaphragms, valves, bellows, etc. are also used to make rubber sheets and wear-resistant parts
2. EPDM EPDM (Ethylene-Propylene-Diene Monomer) solenoid valve The main feature of EPDM is its superior resistance to oxidation, ozone and corrosion. Since EPDM belongs to the polyolefin family, it has excellent vulcanization properties. Among all rubbers, EPDM has the lowest specific gravity. The solenoid valve can absorb a large amount of filler and oil without affecting its characteristics. Therefore, low-cost rubber compounds can be produced. Solenoid valve molecular structure and characteristics: EPDM is a terpolymer of ethylene, propylene and non-conjugated diene. Diolefins have a special structure. Only one of the two bonds of the solenoid valve can be copolymerized, and the unsaturated double bonds are mainly used as cross-links. The other unsaturated one will not become the main polymer chain, but will only become the side chain. The main polymer chain of EPDM is fully saturated. This feature of solenoid valve makes EPDM resistant to heat, light, oxygen, especially ozone. EPDM is essentially non-polar, has resistance to polar solutions and chemicals, has low water absorption, and has good insulation properties. Solenoid valve characteristics: ① low density and high filling; ② aging resistance; ③ corrosion resistance; ④ water vapor resistance; ⑤ superheated water resistance; ⑥ electrical performance; ⑦ elasticity; ⑧ adhesion.
3. VITON Fluorine Rubber (FKM)
The fluorine-containing rubber in the solenoid valve molecule has various types depending on the fluorine content, that is, the monomer structure; the fluorine rubber of the solenoid valve hexafluoride series is better than silicone rubber in high temperature resistance, chemical resistance, and the solenoid valve is resistant to most oils And solvents (except ketones and esters), weather resistance, ozone resistance are good, but cold resistance is poor; solenoid valves are generally widely used in automobiles, motorcycles, B and other products, and seals in chemical plants. The operating temperature range is -20°C. ~260℃, low-temperature resistant type can be used when low-temperature requirements are used, which can be applied to -40℃, but the price is higher.