Nitrile butadiene rubber (NBR) is one of the most widely used sealing ring materials in industrial equipment. It is highly oil-resistant and wear-resistant, and is extensively used in hydraulic systems, speed reducers, pneumatic equipment, and various oil-containing environments. However, even the most common NBR sealing rings can have their service life significantly shortened, and may even experience problems such as leakage, swelling, and failure, if the wrong lubricant is selected.
Nitrile rubber is characterized by good compatibility with mineral oil, hydraulic oil, and grease, but it is sensitive to esters, ethers, and highly polar media. In incompatible oils, it will expand in volume, soften, and lose elasticity. Many companies experience "rapid aging of seals, oil leaks in equipment, and frequent maintenance" because they have chosen lubricants with incorrect base oils or additive systems.
Therefore, in equipment using NBR seals, it is recommended to prioritize mineral oil-based, PAO synthetic base oil, and greases with strong antioxidant properties. Avoid using highly swelling oils containing strong polar substances. In particular, some high-temperature chain oils and ester-based lubricants, if used without understanding the sealing material, can easily cause severe expansion and softening of the seal.
If the sealing ring exhibits the following symptoms, be wary of oil compatibility issues: the sealing ring becomes sticky, thickens, softens, becomes larger, fails to seal properly, or leaks oil from the equipment edges. Replacing the sealing rings will not solve the underlying problem; the solution lies in selecting the right lubricant.
Baoxing provides customized lubricants and greases for the manufacturing industry, offering specialized options for sealing rings made of various materials. We also provide compatibility testing and sample trials for NBR materials, helping companies mitigate risks. Welcome to contact us for inquiries!
