Regarding fasteners, proper lubrication and surface preparation are crucial to ensuring a solid connection. Here is what you need to know to get the best results:
🛝 Lubricants
The type of lubricant you use will depend on the application. For example, you will want to use a heat-resistant lubricant for screws subject to high temperatures. In general, however, the most important thing is to choose a lubricant that will not damage the fastener or the surface it is being installed. We lubricate threaded fasteners not only because it enables them to be removed later but also because it ensures consistent tightening.
Unfortunately, many tools we commonly use to tighten fasteners—such as torque wrenches—do not measure tension. This practice can lead to problems when preloading fasteners without proper precautions. Threaded fasteners work by preloading and 🤸♂️ stretching the bolt. Too much preload and the bolt may exceed its elastic limit and stretch; too little and the bolt may be subject to alternating forces and fatigue.
Most bolts fail due to fatigue caused by under-tightening. Applying a lubricant helps to ensure that the fastener is tightened to the proper tension by providing consistent friction between the threads—preventing galling, which can cause the fastener to seize up or break.
🥌 Surface Preparation
For the fastener to create a strong connection, it is important that both surfaces—the fastener and the surface it is being installed into—are clean and free of debris. Any dirt, dust, or grime can potentially weaken the connection. The best way to clean surfaces is with a solvent compatible with the fastener and the surface it is being positioned. Once the surfaces are clean, you will also want to ensure they are 🏜 dry before proceeding. If installing fasteners into metal surfaces, you may also want to use a rust inhibitor to prevent corrosion and ensure a long-lasting connection.
With these tips in mind, you are well on creating robust and reliable fastener connections. Just be sure to take the time to prepare both surfaces and apply the appropriate lubricant properly, and you will be good to go.