There are a lot of different specialized types of fasteners on the market today. In construction and building companies and services, a common type of anchor found in most inventory rooms is a concrete wedge.
The Look
The unique look of concrete wedge anchors actually provides a very good visual of just how the anchor works inside the concrete wall, floor or ceiling. From the top, these anchors look like a standard bolt, although some have chamfering to allow for easy threading of the bolt. This is actually important as the head of the bolt may need to be tapped to get the anchor in place. The chamfering eliminates the risk of damage to the threads, allowing for easier starting of the nut.
The bottom part of concrete wedge anchors look very different than other bolts or anchors. Typically, these are threaded about one-third to half way down the shaft. At that point, the threading ends and the shaft are unthreaded and tapers down, then expands at the end to the full diameter. Just above this is a collar, which sits between the bottom and the threaded area of the anchor.
The Use
To use concrete wedge anchors, drill a hole that is the diameter of the base of the anchor. The hole is then cleaned to remove dust, and concrete chips and the anchor is inserted into the hole. Threading the washer and nut on the end provides a surface to give the anchor a tap to fully seat it in the hole. Then, tighten the nut which will draw the base up to the bottom of the collar, forcing the collar to expand and wedge the anchor into the concrete.
It is import to verify the anchor is fully set to the correct depth and in the correct location before tightening. Once these are installed, they cannot be removed from the concrete without breaking out the hole.
