Nov.07.2024
The seal is made of an annular cap. It is fixed in the bearing of a ring or gasket, and with another set of ring or gasket contact, or forms a narrow labyrinth gap, in order to prevent lubricating oil leakage and foreign matter invasion. Because of its O-shaped cross-section, it is called an O-shaped seal. Fleyedna Flow introduces you to 11 typical valve sealing rings materials and features.
1. NBR Nitrile Rubber Sealing
Suitable for petroleum-based hydraulic oil, glycol-based hydraulic oil, diester-based lubricants, gasoline, water, silicone grease, silicone oil and other media. It is the most widely used and lowest-cost rubber seal. Not suitable for polar solvents such as ketone, ozone, nitro hydrocarbons, MEK and chloroform.
The general operating temperature range is -40 ~ 120 ℃.
2. HNBR Hydrogenated Nitrile Butadiene Rubber Sealing
It has excellent corrosion resistance, tear resistance compression, deformation resistance, ozone resistance, sunlight resistance, and weathering resistance. Abrasion resistance is better than nitrile rubber.
Suitable for washing machines and automotive engine systems. Not recommended for alcohol, ester or aromatic solutions.
The general operating temperature range is -40~150 °C.
3. SIL Silicone Rubber Sealing
Excellent heat resistance, cold resistance, ozone resistance and atmospheric aging resistance. Which has very good insulating properties. However, its tensile strength is poorer than ordinary rubber and it is not oil-resistant.
Suitable for household appliances such as electric water heaters, electric irons, microwave ovens and so on. It is also suitable for various items in contact with the human body, such as kettles and water dispensers. Not recommended for most concentrated use Solvents, oils, concentrated acids and sodium hydroxide.
The general operating temperature range is -55 ~ 250 °C.
4. VITON Fluorine Rubber Sealing
The high-temperature resistance is better than that of silicone rubber, with excellent weather resistance, ozone resistance and chemical resistance, but poor cold resistance.
It is resistant to most oils and solvents, especially acids, aliphatic hydrocarbons, aromatic hydrocarbons and animal and vegetable oils. Suitable for sealing needs in diesel engines, fuel systems and chemical plants. It is not recommended for use with ketones, low-molecular-weight esters and mixtures containing nitrates.
The general operating temperature range is -20~250 °C.
5. FLS Fluorosilicone Rubber Sealing
Its performance synthesizes the advantages of fluoroelastomer and silicone rubber, with excellent resistance to oil, solvents, fuel and high and low temperatures. It can resist the erosion of oxygen-containing compounds, aromatic hydrocarbon solvents and chlorine-containing solvents.
The general operating temperature range of -50 ~ 200 °C.
6. EPDM Rubber Sealing
It has good weather resistance, ozone resistance, water resistance and chemical resistance. It can be used for alcohols, ketones, and high-temperature water vapor environment sealing.
The general operating temperature range is -55~150 °C.
7. CR Neoprene Sealing
It is particularly resistant to sunlight and weather. It is not afraid of refrigerants such as dichlorodifluoromethane and ammonia and is resistant to dilute acids and silicone lubricants. However, it expands greatly in mineral oils with low aniline points. It tends to crystallize and harden at low temperatures.
It is suitable for a variety of environments exposed to the atmosphere, sunlight, ozone and a variety of flame-retardant, chemical-resistant sealing links. It is not recommended for use with strong acids, nitrohydrocarbons, esters, chloroform and ketone chemicals.
The general operating temperature range is -55~120 °C.
8. IIR Butyl Rubber Sealing
Particularly good airtightness, heat, sunlight and ozone resistance, good insulation and resistance to polar solvents such as alcohols, ketones, esters, etc. It can be exposed to animal and vegetable oils or oxidizable substances.
Suitable for chemical resistance or vacuum equipment. It is not recommended for simultaneous use with petroleum solvents, kerosene or aromatics.
The general operating temperature range is -50 ~ 110 °C.
9. ACM Acrylic Rubber Sealing
Excellent resistance to oil, high-temperature resistance, and weather resistance. But the mechanical strength, compression deflection rate and water resistance are slightly worse.
Generally used in automobile transmission and power steering systems It is not suitable for hot water, brake fluid and phosphate ester.
The general operating temperature range is -25 ~ 170 °C.
10. NR Natural Rubber Sealing
Rubber products have good abrasion resistance, elasticity, tear strength and elongation. However, it is easy to aging in the air, become sticky in the heat, swell and dissolve in mineral oil or gasoline. And alkali-resistant but not resistant to strong acids.
It is suitable for use in automobile brake fluid, ethanol and other liquids with hydroxide ions.
The general operating temperature range is -20 ~ 100 °C.
11. PU Polyurethane Rubber Sealing
The mechanical properties of polyurethane rubber are very good, abrasion resistance and high-pressure resistance are far better than other rubber. Aging resistance, ozone resistance and oil resistance are also quite good, but high-temperature hydrolysis.
Generally used for high-pressure, wear-resistant sealing link.
The general operating temperature range is -45 ~ 90 °C.
The above is an introduction to sealing rings. Fleyenda Flow hopes it will be of reference for you to choose sealing rings.
