Fastening, joining, and bonding require contact between mating surfaces and more contact results in stronger joints. But many mechanical fasteners like nut and bolt assemblies, have only 15% contact between mating surfaces. Imperfections, voids, microscopic cracks and standard tolerances stack up to produce low surface contact, low strength, and poor resistance to vibration. Mechanical fasteners with better surface quality, less porosity, and tighter tolerances improve the mechanical contact area between mating surfaces but at a higher price. Applying an anaerobic adhesive is a better solution because the adhesive flows into the voids and produces nearly 100% contact between mating surfaces. And it is faster with a lower cost than mechanical fasteners.
Threadlockers are a single component anaerobic adhesive and are available as resins, gels, and pastes. They cure to a durable solid when exposed to metal ions in the absence of air, for example between a nut and bolt. Once the anaerobic adhesive is sealed between a nut and bolt and exposed to the metal ions, anaerobics rapidly polymerize to form a thermoset plastic which adheres to the metal components.
Threadlockers do not require mixing so they are easily applied by hand. They improve the holding force of assemblies, and prevent corrosion of the fastener. Threadlockers can be removed with standard hand tools or a power tool, depending on the formula used. Threadlockers cure within minutes after application and fully cure within 24 hours.
Palm Labs Adhesives designs and packages threadlockers in color coded bottles with applicator brushes and tips to make dispensing quick, clean and easy. Purple is designed for screws up to ¼” in diameter and is a low strength removable grade. Blue is a medium strength threadlocker, it is removable, and it is generally suitable for bolts up to ¾” in diameter. Red is high strength threadlocker and is a permanent adhesive designed for bolts up 1 ½” in diameter. Green is a wicking grade adhesive also known as retaining compound and are formulated to increase the strength of non-threaded cylindrical applications. Retaining compounds have become a standard method for assembling slip and press fit assemblies such as bonding shafts bearings rather than using press fits, shrink fits or expensive locknuts. The adhesive prevents lateral movement and protects the joint from corrosion. It can also eliminate locknuts from the assembly, reducing weight and inventory. Retaining compounds also improve performance due to the increased surface contact between the shaft and the bearing.
Best performance results when the adhesives are applied on clean surfaces, although the surface insensitive formulations by Palm Labs Adhesives have overcome many of the issues related to surface contamination. Surface insensitive formulations also work well on plated and anodized surfaces.
There are many choices when selecting the proper adhesive for an application. Call one of Palm Labs Adhesives technical representatives for help and advice. 321-710-4850 or email to your question to [email protected]