Anaerobic adhesives

Anaerobics don’t contain solvents that need to ‘dry.’ In fact, for an anaerobic adhesive to cure, it must come into contact with active metal ions in the absence of oxygen.

The ‘ml’ specification on each adhesive package refers to the amount contained in the bottle. The bottles are only filled halfway because the air prevents the adhesive from curing.

They prevent fasteners from loosening and protect against corrosion. These products also seal the joint.

 To prevent the leakage of liquids or gases from pipe joints.

They can be used on their own or to complement traditional assemblies and allow for less precise machining, which can reduce costs.

No solvent can wick into the joint to break the threadlocker down. The assembly is either removable with hand tools at room temperature, or if not, it requires high temperatures of 230–315°C to separate the parts. These products are thermoset plastics in their cured state and soften at higher temperatures. Therefore, disassembly must be carried out while the adhesive is at its higher softening point. The material weakens when exposed to heat but regains its strength upon cooling back to room temperature, unless the heat has burned the threadlocker. At 230–315°C, the threadlocker will burn. Once burned, the resistance is that of charred plastic, which is why it’s best to disassemble while everything is still hot. Solvents like methyl ethyl ketone and methylene chloride can be used to clean up any residue after disassembly.

We recommend the use of primers such as SF 7649 and SF 7471 with most anaerobics where both parts are classified as "inactive" metals. These metals lack the presence of iron or copper content and thus, lack the "active" metal ions required to fully cure the product in 24 hours. These metals include plated parts, stainless steel, galvanized steel and anodized aluminum, to name a few. If, on the other hand, both or at least one part is an "active" metal, such as plain steel, brass, bronze, copper or iron, there is no need to use a primer to ensure full cure in what is typically 24 hours at room temperature. A primer will be helpful to accelerate the cure in colder temperatures or where there are larger gaps between the metal components.

Yes. Anaerobics can be used on oil-impregnated parts. Simply wipe the part clean before applying the product. More oil-tolerant products, such as 638 and 243 are good choices because they have better ability to cut through the oil to cure properly and bond and seal effectively once hardened.