Threadlockers
Threadlockers, also called thread locking compounds or adhesives, secure and seal threaded fasteners such as bolts, nuts, screws and studs. Unlike mechanical locking devices, LOCTITE® threadlockers form a durable bond that helps prevent loosening, maintains clamp load, combats corrosion and improves assembly reliability. These anaerobic adhesives cure in the absence of air to form a strong thermoset plastic between the threads.
Available in different strengths and formulations, LOCTITE® threadlockers support maintenance, repair and manufacturing applications across MRO and OEM environments.
Types of threadlockers
LOCTITE® threadlockers are color-coded by strength and application type:
- Red Threadlocker: High-strength, permanent thread lock for critical and heavy-duty assemblies. It may require heat for disassembly.
- Blue Threadlocker: Medium-strength adhesive that can typically be disassembled with hand tools, making it suitable for general maintenance and automotive applications.
- Green Threadlocker: Wicking threadlocker for pre-assembled fasteners, set screws and hard-to-reach areas. It offers medium-to-high strength.
- Purple Threadlocker: Low-strength solution for small screws and delicate assemblies, including aluminum and brass components.
Key features and benefits
LOCTITE® threadlockers help prevent loosening, leakage and corrosion while reducing downtime and maintenance requirements. Standard formulations offer temperature resistance from -65°F to 300°F, with specialized high-temperature products also available. They come in liquid, stick, gel and paste forms to suit different assembly needs.
When selecting a threadlocker, consider the required strength, disassembly needs, vibration levels, thread size and application conditions.
How to apply threadlockers
- Clean both threads to remove contaminants.
- Ensure the threads are completely dry.
- Apply a few drops of threadlocker adhesive to the thread.
- Tighten the fastener.
- Allow the threadlocker to cure according to the technical data sheet (TDS).
Liquid threadlockers are the most common format, while sticks and tapes can provide cleaner application for overhead or pre-dispensed uses. Threadlocker pastes are also available for demanding applications.
Threadlocker applications
Threadlockers can be used for a wide range of threaded fastener applications, including through holes, blind holes, post-assembly, overhead applications and pre-applied solutions. Low-strength products are suitable for small screws and delicate assemblies, while medium-strength products allow easier maintenance and high-strength threadlockers support critical industrial assemblies.
Choosing the right LOCTITE® threadlocker helps keep threaded assemblies secure and reliable while simplifying maintenance and reducing the risk of loosening.