Consists of one or a few parts of the annular cover, fixed in a bearing ring or washer on and contact with another ring or washer or form a labyrinth of narrow gap and prevent the lubricating oil leakage and outside intrusion. The sealing ring is a circular rubber ring, because its section is O type, so it is called o-ring. It is the most widely used in hydraulic and pneumatic transmission system. Usually in Taiwan, the Japanese company is called the O Ring.

A nitrile rubber, NBR seal: suitable for oil and hydraulic oil, glycol hydraulic oil, the second ester lubricating oil, gasoline, water, silicone grease, silicone oil and other medium. It is the most widely used and cheapest rubber seal. It is not suitable for polar solvents such as ketone, ozone, nitrohydrocarbon, MEK, and chloroform. General use temperature range for - 40 ~ 120 ℃.

HNBR hydrogenated nitrile rubber sealing ring: excellent corrosion resistance, tensile and compression deformation characteristics, resistance to ozone, sunshine, good weather resistance. It has better abrasion resistance than butyronitrile rubber. It is suitable for washing machine, automotive engine system, and the refrigeration system of new environment-friendly cold vector R134a. It is not recommended for alcohol, ester, or aromatic solutions. General use temperature range for - 40 ~ 150 ℃.

SIL silicone rubber packing: excellent heat resistance, cold resistance, ozone resistance and atmospheric aging. It has good insulation. But the tensile strength is lower than the general rubber and it is not oily. Applicable to household appliances such as electric water heater, electric iron, microwave oven etc. It also applies to all kinds of things that are in contact with the human body, such as kettle, water fountain. It is not recommended for most concentrated solvents, oils, strong acids and sodium hydroxide. General use temperature range is - 55 ~ 250 ℃.

VITON fluorine rubber seal: high temperature resistance is superior to silicon rubber, excellent weathering, ozone resistance and chemical resistance, and cold tolerance. Most of the oil and solvents have resistance, especially acids, aliphatic hydrocarbons, aromatic hydrocarbons and animal and plant oils. Suitable for diesel engine, fuel system and chemical plant. It is not recommended to use ketone, low molecular weight of ester and nitroglycerin mixtures. General use temperature range is - 20 ~ 250 ℃.

FLS fluorosilicone rubber seal: its properties include the advantages of fluorine rubber and silicone rubber, which is good for oil, solvent, fuel oil and high temperature resistance. An erosion of a compound containing oxygen, solvents containing aromatic hydrocarbons, and solvents containing chlorine. It is commonly used for aviation, aerospace and military purposes. The rubber foamed coil manufacturer does not recommend the exposure to ketone and brake oil. General use temperature range is - 50 ~ 200 ℃

EPDM triethylene propylene rubber seal: good weathering, ozone resistance, water resistance and chemical resistance. It can be used in alcohols and ketones, and can be used in the sealing of hot water vapor environment. Apply to sanitary ware, car radiator and auto brake system. It is not recommended for food use or for exposure to mineral oils. General use temperature range is - 55 ~ 150 ℃.

7, CR neoprene rubber seal ring: good for sunshine and weather. It is not afraid of refrigerants, such as dichlorodifluoromethane and ammonia, which are resistant to dilute acid and silicone-resistant grease, but in the mineral oil, which is low in aniline, it expands. It is easy to crystallize and harden at low temperature. It is suitable for all kinds of sealing parts of atmosphere, sunshine, ozone and all kinds of fire resistant and chemical corrosion. It is not recommended for the use of strong acids, nitrohydrocarbons, esters, chloroform and ketones. General use temperature range is - 55 ~ 120 ℃.

Eight, IIR butyl rubber ring: air tightness is very good, heat resistance, sunshine, ozone resistance is good, insulation performance is good. Good resistance to polar solvents such as alcohol, ketone and ester can be found in animal and plant oils or oxides. Suitable for chemical or vacuum equipment. It is not recommended to be used in conjunction with petroleum solvents, kerosene or aromatic hydrocarbons. General use temperature range is - 50 ~ 110 ℃.

Nine, ACM acrylate rubber seal: have excellent resistance to oil, high temperature resistance, weather resistance are good, but the mechanical strength, compression deformation rate and resistance to water is a bit poor. It is commonly used in automotive transmission system and power steering system. It is not suitable for hot water, brake oil, phosphate. General use temperature range is 25 ~ 170 ℃.

NR natural rubber seal ring: rubber products have good abrasion resistance, elasticity, tensile strength and elongation. But in the air, it is easy to age, and when it is hot and sticky, it can expand and dissolve in mineral oil or gasoline, but it is resistant to strong acid. Suitable for use in liquids with hydroxide ions such as brake oil and ethanol. General use temperature range is - 20 ~ 100 ℃

The mechanical properties of polyurethane rubber are very good, and the resistance and high voltage performance are superior to other rubber. Aging, ozone resistance and oil tolerance are also good, but high temperatures are easy to hydrolyze. Generally used for high pressure and wear sealing, such as hydraulic cylinder. General use temperature range is - 45 ~ 90 ℃.

Metal rubber seal ring: made of stainless steel wire, without any rubber content, with strong usage characteristics. For example: maintain normal work in high vacuum, high temperature, high radiation, and corrosion. Seal skin according to different purpose by different materials such as stainless steel, copper, ptfe, such as material, was enshrouded in the metal rubber components as the lining core, seal with high strength, good effect, can be repeated use, etc. The sealing ring is made of different metal wires, and is suitable for different pressure situations. General use range is - 80 ~ 800 ℃. This sealing ring is expensive because of high cost. But good performance, widespread use of the environment, is recognized by people.