A threadlocker is an anaerobic adhesive used on threaded metals that cures at room temperature in the absence of air. The adhesive completely fills the gaps between mating threads to lock and seal the threaded assembly.

Benefits of Using LOCTITE^® Threadlockers

• Locks mating threads to prevent loosening from vibration & shock
• Seals against fluids & corrosion
• Provides lubricity to achieve controlled torque during assembly
• Works on active metals (e.g., brass, copper) as well as passive metals (e.g., stainless steel, plated surfaces)
• Resists extreme temperatures
• Applies easily and cures rapidly

How to Choose a LOCTITE^® Threadlocker

When choosing a threadlocker, there are four things to consider:

1. Strength

• Low Strength (Purple): Ideal for fasteners <1⁄4" (6 mm). Easy disassembly using hand tools
• Medium Strength (Blue): Designed to be removable with standard hand tools on 1⁄4" to 3⁄4" fasteners
• High Strength (Red): Designed to deliver high strength on 1⁄4" to 3⁄4" (6 mm to 22 mm) fasteners. For removal, it may require localized heat (>550°F/260°C), hand tools, and disassembly while hot

2. Viscosity

• Liquid Formulas: Everyday assembly; ideal for fine threads and blind holes
• Semisolid Formulas: Pocket-friendly, ideal for overhead applications
• Tape Formula: Pocket-friendly; controlled application; can be pre-applied several days before assembly

3. Application Methods

• Pre-Applied: QuickTape threadlocker can be applied beforehand on bolts that are waiting to be assembled
• Pre-Assembly: Most LOCTITE® liquid threadlockers are designed to be applied at the moment that parts will be assembled
• Post-Assembly: Wicking grade formula can be applied on parts that are already assembled

4. Materials Being Assembled

• All LOCTITE^® Threadlockers: Metal-to-metal applications
• LOCTITE^® 425 Assure: Plastic-to-plastic, plastic-to-metal applications

Learn More

Threadlocking User's Guide 

LOCTITE^® Threadlocker Packaging is Recycleable

Henkel is pleased to partner with TerraCycle^®, an innovative recycling company that offers recycling solutions for the typically non-recyclable.

Through this partnership we have created the Adhesive Recycling Program for our customers, allowing you to recycle LOCTITE^® adhesive packaging and reduce the amount of waste that is sent to a landfill or incinerator.

LOCTITE^® Success Stories