O-ring issue

EPDM is a commonly used high-performance rubber material, typically used in the production of O-rings. During use, the O-ring comes into contact with various chemicals, including oils and other liquids. If the oil contains harmful chemicals, it may cause the O-ring to age, harden, or become brittle, thereby losing its sealing ability. Therefore, it is very important to choose an O-ring material that is suitable for the surrounding environment. If you are unsure whether a EPDM O-ring is suitable for a specific oil, it is recommended to consult relevant professionals or O-ring suppliers. .

Refer to the advantages, disadvantages, and application areas of O-rings made from different materials at https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=3384459&shareuid=301199. EPDM (Ethylene propylene Rubber) is formed by the copolymerization of ethylene and propylene; its main chain does not contain double bonds, which gives it excellent heat resistance, aging resistance, ozone resistance, and stability. However, it cannot be vulcanized using sulfur. To solve this problem, a small amount of a third component with double bonds is introduced into the EP backbone, allowing it to be vulcanized with sulfur to form EPDM; its typical operating temperature range is -50 to 150°C. It exhibits excellent resistance to polar solvents such as alcohols, glycols, ethylene glycol, and phospholipid-based hydraulic fluids. (1) Advantages: It has good weather resistance and ozone resistance. It has excellent water resistance and chemical resistance. Alcohols and similar substances can be used. Resistant to high-temperature steam, and has good impermeability to gases. (2) Disadvantages: Not recommended for use in food applications or exposure to aromatic hydrogens. Seals for high-temperature steam environments. Seals or parts for bathroom fixtures. Rubber components in the braking system. Seals in the radiator (car radiator).

In addition to concerns about whether EPDM ages when exposed to oils, there are also other types of failure issues that can occur as a result of contact with oils. EPDM is generally not recommended for use in the presence of oils. You can check the type of rubber used for the oil seal.

Ethylene-propylene rubbers must not come into contact with mineral oil; such contact will cause swelling, leading to the rapid failure of the O-ring.