LOCTITE® 566 is a thread sealant designed for sealing coarse threads in metal pipes and fittings. It cures slowly to allow proper alignment and provides a reliable, resistant seal against leakage of industrial fluids and gases.
LOCTITE® 566 is a high-performance liquid thread sealant that fills the gaps between metal pipe threads, curing anaerobically to form a strong, pressure-resistant seal. It is specifically formulated for use on coarse-threaded metal fittings, offering excellent chemical resistance and long-term durability. The slow cure time allows installers to position and align components before full cure, ensuring flexibility during assembly. It resists vibration, prevents loosening, and eliminates leakage caused by poor thread engagement or surface imperfections. LOCTITE® 566 is particularly effective in industrial environments where fluids and gases are under high pressure.
Colour: Brown
Viscosity: Medium to high
Cure method: Anaerobic (cures in absence of air between metal surfaces)
Service temperature range: –55 °C to +150 °C
Maximum thread size: Up to 3 inches
Chemical resistance: Excellent against oils, fuels, water, and many chemicals
Primary Chemistry: Methacrylate ester
Stops leaks in coarse-threaded metal pipes that may otherwise occur with traditional sealing methods. Eliminates the risk of fittings loosening due to vibration or fluctuating temperatures. Reduces maintenance costs by preventing seal failures in fluid and gas systems. Simplifies installation by providing a single product that seals and locks threads. Removes inconsistencies and mess associated with tapes and pastes, ensuring professional, repeatable results.
LOCTITE® 566 is applied to clean, dry male threads before assembly. The slow-curing formulation allows installers to adjust or reposition fittings during assembly. Once cured, it provides a robust seal that resists vibration and high pressures. Ideal for use in hydraulic systems, compressors, pumps, industrial piping, and gas lines.
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