Solution to Securing Threaded Fasteners
Mechanical locking devices, such as split ring washers, nylon insert nuts, and serrated tooth washers were invented to solve the common problem of loosening that happens in most threaded assemblies. However, the reality is that they don’t “lock” the assemblies and can’t maintain clamp load. These devices often loosen under vibration, thermal expansion, bending, and/or improper torque.
Threadlockers, or threadlocking adhesives, are the solution to this problem. Applied between two mating threads, these liquid threadlocker adhesives secure nuts, bolts, and threaded fasteners in place. They cure to form a strong bond that prevents loosening, ensuring assemblies retain clamp load over time.
Threadlocking compounds can effectively reduce the impact of costly failures, repairs, maintenance, and downtime. Applied to one or two threads before assembly, LOCTITE® threadlockers push the air between the threads out as the fastener is tightened. The anaerobic threadlocker material cures in the absence of air to form a strong, thermoset plastic that locks threads and joints in place.
LOCTITE® threadlockers can also lower the effect of corrosion in threaded components and help to prevent leaks in your assemblies. Applicable across both maintenance, repair, and operations (MRO) and original equipment manufacturing (OEM), LOCTITE® threadlockers improve reliability, eliminate failure, and boost productivity in your operations.
Our threadlockers are single-component liquid adhesives that secure nuts, bolts, and threaded fasteners. They are designed to eliminate air gaps that, combined with vibration and shock that allow for loosening in threads. This is achieved by forming a strong bond between the threads that holds everything tightly in place with a controlled strength thread lock.
All LOCTITE® threadlockers have a broad temperature resistance of -65°F to 300°F, while some threadlockers are designed for high temperatures up to 650°F. Threadlockers were LOCTITE®’s first product line. They combine a mix of complex chemistry and engineering. Simply put, this product is an anaerobic adhesive applied by drops to the threads of fasteners. It then cures to a hard thermoset plastic that locks the threads together. They are used only for metal-to-metal applications.
Differences Between Threadlocker Grades
LOCTITE® Purple Threadlocker
LOCTITE® purple threadlocker, also known as LOCTITE® 222™, has become one of our most successful products. LOCTITE® 222™ cures in 24 hours. This low strength threadlocker can be used on metals such as aluminum and brass and offers a lot of flexibility to the user.
LOCTITE® purple threadlocker has many uses, from carburetor screws to eyeglasses, to small screws on laptops. Due to the threadlocker being low strength, it can be removed with the same tool used to put the project together. It is available in an easy-to-use liquid application, which makes the product especially efficient with very small screw applications, less than ¼ inches in diameter.
LOCTITE® Blue Threadlocker
LOCTITE® blue threadlocker is medium strength threadlocker adhesive. This product cures fully in 24 hours and can be disassembled with hand tools.
Blue threadlockers are removable with standard hand tools on 6mm to 20mm fasteners, have fast fixture times, and are available in liquid, stick, paste and gel form. Moreover, there is also LOCTITE® QuickTape 249™ Threadlocker, the one and only of its kind globally. A primerless grade blue threadlocker is available as well.
LOCTITE® Green Threadlocker
LOCTITE® green threadlocker is recommended for locking preassembled fasteners, e.g. electrical connectors and set screws, and prevents against loosening, rust, and corrosion.
This wicking grade threadlocker is categorized as a medium-to-high-strength adhesive. Also available in a liquid form, LOCTITE® green wicking threadlocker cures in 24 hours and can be removed with hand tools and, in rare instances, may require heat to assist when threads have excessive engagement lengths.
LOCTITE® Red Threadlocker
LOCTITE® red threadlocker is the highest strength of threadlocker adhesive. This product cures fully in 24 hours and is available in both a liquid and as a semisolid anaerobic.
The red high strength threadlocker products are so powerful they may require heat to be disassembled. A primerless grade red threadlocker is also available.
When Choosing a Threadlocker
And Things to Consider
Our products are available in many different grades to cater to a broad array of applications, from auto maintenance and boat maintenance to a wide range of household repairs. These different grades or thread lock types are color-coded to help you distinguish one threadlocker type from another. Our user guide contains a threadlocker chart that details the properties of each product. The color refers to the actual substance, but all the bottles are red in color. The red bottle is actually a LOCTITE® trademark. It’s what visually distinguishes LOCTITE® threadlockers from any other brand.
Choosing between a LOCTITE® red, blue, green, or purple threadlocker will depend on the specific needs of your project and the threadlocker strength you require. To find the right threadlocker for your task, key considerations should include:
- Maintenance and disassembly needs
- Temperature requirements of application
- Application strength and vibration levels
- Type of assembly
- Thread size
- Application area and location