An expansion bolt is a combination of a nut, a bolt and a sleeve. It is usually utilized when working on concrete and bricks. It can produce a firm grip in heavy load applications.
When installing an expansion bolt, you need to pre-drill a hole which is slightly larger than the size of the bolt. Then, insert the bolt into the hole and tighten the bolt. While the bolt is tighten, the sleeve will expand to grasp the material surrounding it. Take note that the size of the drilled hole should be larger than the bolt as the sleeve will expand and fit itself in the hole nicely.
Expansion bolts are available in different designs. One of them has a tapered nut which when tighten to the bolt head will cause the sleeve to expand.The other more common design has the metal cone-nut configuration where tightening of the bolt will cause the metal cone to exert force on the sleeve. Eventually, the sleeve will swell to create a strong joint.
These bolts are very flexible tools as they can tolerate holes which are not properly aligned and provide strong connection. They will also work reliably in materials like concrete with poor quality as they can provide large contact area to hold the joint. Another advantage in using expansion bolts would be that they are suitable to create joints when only one side of the attachment is accessible.
You need to apply a suitable force when tightening the bolt. Over tightening of the fastener may break it and prevent its removal. However, if you do not tighten the bolt with adequate force, it may not be able to hold heavy application and joint.
These tools are usually used during rock climbing. Climbers will fix the bolts into rock areas which are deemed unsafe and attach their climbing gears to the bolts for support while climbing to prevent a fall. The bolts would be inserted into holes which have been drilled into the rock. Besides, these tools are also commonly used in installing handrail, barrier, ceiling and other fixtures.
These products are commonly manufactured from material like stainless steel which makes strong and sturdy bolts. They are also coated with an extra layer of cadmium or zinc to prevent corrosion from air and water to produce more lasting bolts. The bolts are available in different diameters to fulfill different fastening needs for various materials. Besides various diameters, they also come in varying lengths for applications of different loads.