Thread lock adhesive, also known as thread locking fluid or threadlocker, is a liquid resin which is applied to threaded fasteners to prevent self-loosening, leakage and corrosion. Threadlock adhesive, when applied to the fastener threads, hardens (or cures) to a tough solid when exposed to metal ions in the absence of air (anaerobic). This curing method allows the sealant to flow evenly into the grooves of the threads and gradually harden. The hardened adhesive provides increased friction between the mating threads for a secure vibration proof connection. The adhesive also acts as a seal and protects the joint from corrosion caused by moisture, fluids and gasses.
Types of Threadlocking Adhesive
Threadlocking fluid is available in different strengths and viscosity to suit specific applications
Low Strength - this sealant is used on screws up to one-quarter of an inch in diameter. These screws include adjustment and calibration screws, gauges, meters and other fastenings that require regular adjustment. Low strength threadlock allows the fasteners to be easily removed
Medium Strength - this is used on fasteners up to three-quarter of an inch in diameter. These fasteners are typically used in machine tools and presses, pumps, compressors and mounting bolts. This allows for disassembly using hand tools.
High Strength - this is used on fasteners up to one inch in diameter which are used in permanent assemblies such as heavy equipment. High strength thread locking adhesive provides resistance against a high degree of vibration and offers the highest holding ability.
Low Viscosity Penetrating Adhesives - this sealant is for use on pre-assembled fasteners.
Other varieties of thread lock adhesive are available that are surface insensitive or have high temperature, chemical resistant or extreme vibration resistant formulations. Threadlocking adhesives are usually colour coded to indicate strength and whether they can be removed.
Benefits
- Prevents unwanted movement or loosening due to vibration
- Prevents corrosion between the threads
- Prevents leakage
- Good temperature resistance
- Improves torque control during assembly
- Lowers maintenance and manufacturing costs by preventing seizing and fastener loosening
- Easy to dispense and apply
