Anaerobic adhesive, threadlocker and retainer

Anaerobic adhesive is usually a one-part methacrylate liquid that stays uncured while exposed to air but polymerises when confined between close-fitting metal surfaces. Metal ions help trigger the reaction. That is why threadlocker cures inside an assembled nut and bolt but a spill on the bench may remain liquid. It is also why cure is slower on passive metals such as stainless steel, plated parts and aluminium, especially when cold. An activator can help, but it may shorten working time and change final performance. The family includes low, medium and high-strength threadlockers, cylindrical retaining compounds, flange sealants and pipe-thread sealants. They are not interchangeable. Choose the grade by gap, viscosity, strength and whether later dismantling is required. Anaerobic products suit metal fasteners, bearings, bushes, shafts and rigid metal flanges. They do not cure properly in a wide open gap, on most plastics or between non-metal faces unless the system is designed and activated for that use. Some can attack or stress-crack susceptible plastics. Oil-tolerant does not mean that a visibly greasy joint needs no cleaning. Remove loose oil and dirt when you can. Full cure is usually much slower than fixture, so do not pressure-test or fully load the assembly at the first sign of handling strength.

Locking metal nuts and bolts against vibration; retaining bearings, gears, pulleys and bushes on shafts; sealing rigid machined flanges; sealing compatible metal pipe threads; filling small clearance in cylindrical metal assemblies.

Clean dirt, loose corrosion and heavy oil. Dry solvent cleaner before assembly. Check the maximum gap and metal activity in the TDS. Use the specified activator on passive metal or at low temperature when required, and allow its carrier to evaporate. Apply enough to wet the engaged threads or cylindrical area, assemble promptly and do not disturb before fixture.