Seals are materials or parts that prevent fluid or solid particles from leaking from adjacent mating surfaces and prevent external impurities such as dust and moisture from invading the internal components of machine equipment. It is a fundamental component and accessory in the main industries of China's national economy, such as national defense, chemical industry, petroleum, coal, transportation, and machinery manufacturing, and plays a significant role in the development of the national economy.
Rubber sealing rings are generally made of nitrile rubber, natural rubber, chloroprene rubber, ethylene propylene rubber, fluororubber, silicone rubber, and blended rubber. The sealing ring is mainly used to prevent oil, water, corrosion, and gas leakage.
According to the different materials used for sealing rings, there are different classifications in terms of properties:
1. High temperature resistant sealing ring, 2. High pressure resistant sealing ring, 3. Corrosion resistant sealing ring, 4. Wear resistant sealing ring
Comparison of Various Rubber Sealing Ring Materials
A circular cover composed of one or several parts, fixed to one ring or washer of a bearing and in contact with another ring or washer or forming a narrow labyrinth gap, to prevent lubricating oil leakage and foreign object invasion. A sealing ring is a rubber ring with a circular cross-section, which is called an O-ring due to its O-shaped cross-section. It is the most widely used type in hydraulic and pneumatic transmission systems. Usually referred to as O Ring in Taiwanese and Japanese enterprises.
1、 NBR nitrile rubber sealing ring: suitable for use in petroleum hydraulic oil, glycol hydraulic oil, diester lubricating oil, gasoline, water, silicone grease, silicone oil and other media. It is currently the most widely used and cost-effective rubber seal. Not suitable for polar solvents such as ketones, ozone, nitrohydrocarbons, MEK, and chloroform. The general temperature range for use is -40~120 ℃.
2、 HNBR hydrogenated nitrile rubber sealing ring: It has excellent corrosion resistance, tear resistance, and compression deformation resistance, as well as good ozone resistance, sunlight resistance, and weather resistance. It has better wear resistance than nitrile rubber. Suitable for washing machinery, automotive engine systems, and refrigeration systems using a new environmentally friendly refrigerant R134a. It is not recommended to use in alcohol, ester, or aromatic solutions. The general temperature range for use is -40~150 ℃.
3、 SIL silicone rubber sealing ring: It has excellent heat resistance, cold resistance, ozone resistance, and atmospheric aging resistance. Has excellent insulation performance. But the tensile strength is worse than that of ordinary rubber and does not have oil resistance. Suitable for household appliances such as electric water heaters, irons, microwaves, etc. It is also suitable for various items that come into contact with the human body, such as water bottles, water dispensers, etc. It is not recommended to use in most concentrated solvents, oils, concentrated acids, and sodium hydroxide. The general temperature range for use is -55~250 ℃.
4、 VITON fluororubber sealing ring: It has better high-temperature resistance than silicone rubber, excellent weather resistance, ozone resistance, and chemical resistance, but poor cold resistance. It has resistance to most oils and solvents, especially acids, aliphatic hydrocarbons, aromatic hydrocarbons, and animal and vegetable oils. Suitable for sealing requirements of diesel engines, fuel systems, and chemical plants. It is not recommended to use in ketones, low molecular weight esters, and mixtures containing nitrate. The general temperature range for use is -20~250 ℃.
5、 FLS fluorosilicone rubber sealing ring: Its performance combines the advantages of fluorosilicone rubber and silicone rubber, with excellent oil resistance, solvent resistance, fuel oil resistance, and high and low temperature resistance. It can resist the erosion of oxygen-containing compounds, solvents containing aromatic hydrocarbons, and solvents containing chlorine. Generally used for aviation, aerospace, and military purposes. Manufacturers of rubber foam coils do not recommend exposure to ketones and brake oil. The general temperature range for use is -50~200 ℃.
6、 EPDM EPDM sealing ring: It has good weather resistance, ozone resistance, water resistance, and chemical resistance. It can be used for alcohols and ketones, as well as for sealing in high-temperature water vapor environments. Suitable for bathroom equipment, car radiators, and car brake systems. Not recommended for food use or exposure to mineral oil. The general temperature range for use is -55~150 ℃.
7、 CR chloroprene rubber sealing ring: It has excellent resistance to sunlight and weather. Not afraid of refrigerants such as dichlorodifluoromethane and ammonia, resistant to dilute acids and silicone grease lubricating oils, but with a large expansion in mineral oils with low aniline points. Easy to crystallize and harden at low temperatures. Suitable for various environments that come into contact with the atmosphere, sunlight, ozone, and various sealing links that are resistant to combustion and chemical corrosion. It is not recommended to use in chemicals such as strong acids, nitrohydrocarbons, esters, chloroform, and ketones. The general temperature range for use is -55~120 ℃.
8、 IIR butyl rubber sealing ring: It has excellent airtightness, heat resistance, sunlight resistance, ozone resistance, and good insulation performance; Has good resistance to polar solvents such as alcohols, ketones, esters, etc., and can be exposed to animal and vegetable oils or oxides. Suitable for chemical resistant or vacuum equipment. It is not recommended to use it together with petroleum solvents, kerosene, or aromatics. The general temperature range for use is -50~110 ℃.
9、 ACM acrylic rubber sealing ring: It has excellent resistance to oil, high temperature resistance, and weather resistance, but its mechanical strength, compression deformation rate, and water resistance are slightly poor. Generally used in automotive transmission systems and power steering systems. Not suitable for use in hot water, brake oil, and phosphate esters. The general temperature range for use is -25~170 ℃.
10、 NR natural rubber sealing ring: Rubber products have good wear resistance, elasticity, tensile strength, and elongation. But it is prone to aging in the air, becomes sticky when exposed to heat, expands and dissolves easily in mineral oil or gasoline, and is alkali resistant but not strong acid resistant. Suitable for use in liquids containing hydroxide ions such as automotive brake oil and ethanol. The general temperature range for use is -20~100 ℃.
11、 PU polyurethane rubber sealing ring: The mechanical properties of polyurethane rubber are very good, and its wear resistance and high pressure resistance are far superior to other rubbers. Aging resistance, ozone resistance, and oil resistance are also quite good, but they are easily hydrolyzed at high temperatures. Generally used in high-pressure and wear-resistant sealing processes, such as hydraulic cylinders. The general temperature range for use is -45~90 ℃.
12、 Metal rubber sealing ring: Made of stainless steel wire, it does not contain any rubber components and has strong usage characteristics. For example, maintaining normal operation in high vacuum, high and low temperature, strong radiation, and various corrosive environments. The sealing ring skin is made of different materials such as stainless steel, copper, polytetrafluoroethylene, etc. according to different purposes. The metal rubber components covered are used as lining cores, which have the advantages of high sealing strength, good effect, and reusability. The sealing ring lining core is a component made of different metal wire diameters and densities, suitable for different pressure situations. The general usage range is -80~800 ℃. This type of sealing ring is relatively expensive due to its high cost. However, its excellent performance and wide range of usage environments have been unanimously recognized by people.
Future market for rubber seals in rubber products, bringing forth new ideas through innovation
1. In today's era, with the progress of technology and the rapid development of China's automobile and industry, especially the emerging materials of rubber products, and also because people's requirements for automobiles are becoming higher and higher, the requirements for automobile sealing are also increasing. Therefore, rubber seals are also constantly innovating.
2. The rationality of the use structure, humanization of design, flowability and automation of production process, safety, environmental protection, recyclability, aesthetic matching, and diversity of rubber sealing products in various industries are all the product performance that rubber product enterprises need to consider now.
Rubber seals have a promising future and a large market, playing a very important role in sealing
1. In recent years, China's rubber product industry has achieved gratifying results, especially in the automotive and industrial industries. The rubber products produced are not only supplied to domestic demand, but also exported to some developed countries. Currently, rubber products are highly competitive both domestically and internationally, and there is still great room for exploration in the market space of the rubber product industry.
2. The application range of rubber seals in rubber products will become increasingly broad, so the development potential and prospects are very attractive. Its rapid development will also have a significant and far-reaching impact on the upstream and downstream industrial chains of the rubber product industry. I believe that the future rubber product industry and rubber seals will not be a single industry development prospect, but rather a combination of the common development of various industries. Therefore, the future market and prospects of rubber seals in rubber products will be very promising; So the rubber product industry has profound significance in enhancing the profitability, capability, and quality level of rubber seals.
