antiseize

Antiseize, or anti-seize, refers to lubricants and pastes applied to threaded fasteners and joints to prevent galling, corrosion, and seizure during installation and service. By reducing metal-to-metal adhesion and protecting threads from moisture and chemicals, antiseize helps ensure easier disassembly, consistent torque, and longer component life in demanding environments. It is not a substitute for appropriate torque, gaskets, or seals.

Most antiseize compounds are pastes or greases that contain a carrier oil and a solid lubricating phase. Common solid lubricants include zinc, aluminum, copper, graphite, and molybdenum disulfide. Some formulations are designed for high temperatures or for oxygen-service and use non-petroleum carriers. Many products are electrically conductive due to metal particles.

Typical uses span automotive, industrial, marine, and aerospace settings. They are applied to spark plug threads, exhaust fasteners, valve stems, flange bolts, and other threaded joints exposed to heat, salt, or corrosive media, helping prevent corrosion-induced seizing and making future maintenance easier. It can also aid in preventing galling when joining dissimilar metals.

Application notes and cautions: apply a thin, even layer to clean threads and mating surfaces, avoiding gasket faces unless the product specifies otherwise. Lubrication alters the torque-tension relationship, so follow manufacturer torque values and recheck after heating. Do not use petroleum-based antiseize on oxygen systems unless the product is specifically rated for oxygen service. Store and handle per label instructions.