How to Use Expansion Bolts?
2 Answers
Steps for using expansion bolts: 1. Determine the installation position and mark it to avoid forgetting; 2. Drill a hole: Use an electric drill, and the depth should be based on the length of the expansion bolt; 3. After drilling, clean the hole thoroughly; 4. Insert the outermost tube; 5. Place the expansion bolt and tighten the nut to secure it. Expansion bolts, generally referred to as metal expansion screws, consist of components such as a screw rod and an expansion tube. The fixing principle of expansion screws relies on the wedge-shaped slope to generate frictional grip force through expansion. They are a special type of threaded fastener used to secure pipelines, supports, hangers, or equipment to walls, floors, or columns.
I recently installed a set of roof racks on my family car using expansion bolts. First, choose the right size—the bolt diameter should match the roof holes, neither too thick nor too thin. After measuring the position, drill holes with a drill bit—the hole depth should match the bolt length, and the diameter should be slightly smaller than the bolt to ensure a tight expansion when fastened. Before inserting the bolt, remember to clean out dust and debris from the hole, or it won’t hold securely. Then, hand-tighten the bolt into place and use a wrench to turn it all the way until you hear a 'click,' indicating it has expanded. Don’t rush to use it after installation—check by pulling to see if it wobbles, and recheck after a few days of driving over bumps to confirm no loosening. A reminder: if the hole is drilled too large, you’ll need to relocate it—I made this mistake before and nearly damaged the car’s underbody while redrilling. During regular maintenance, take a quick look to prevent corrosion and extend its lifespan.
