Loctite 518 Gasket Eliminator Flange Sealant

The Loctite 518 Gasket Eliminator Flange Sealant is a red, medium-strength anaerobic gel that forms gaskets in place between rigid metal faces and flanges. It resists low pressures straight after assembly, fills gaps up to 0.25 mm and fixtures on steel in about 25 minutes. It cures despite minor oil and cleaner residue, works on steel and low-copper aluminium, and handles -55°C to +150°C. Available in 25 ml, 50 ml and 300 ml.

Apply a continuous bead, rolled film or screen print to one clean flange face — coat both when using a pen roller on gaps above 0.125 mm — and tighten up soon after assembly to avoid shimming; the thixotropic gel stays where it is placed and fluoresces under UV for inspection. It is not normally recommended for plastics, particularly thermoplastics, or for oxygen-rich systems and strong oxidisers. Consult the Safety Data Sheet before use.

At a glance

• Gearbox and engine casings — form-in-place flange gaskets
• Pump and compressor housings — replacing pre-cut gaskets
• Aluminium and mild steel flanges — active and passive metals
• Production gasketing — bead, roller or screen print

Full specifications, applications, features and important limits are in the tabs below.