Different types of concrete wedge anchors are manufactured for use in different applications. The only differences between the types of concrete wedge anchors are the material that they are made from and the plating or coating that is used for improving the corrosive resistance of the steel.
Carbon Steel – the carbon steel concrete wedge anchor comes with either zinc plating for indoor applications where moisture is not present or hot-dipped galvanized coating for outdoor applications where moisture may be present.
Stainless Steel 303/304 – different manufacturers use either the 303 or 304 stainless steel for their concrete wedge anchors. They are used in applications where moisture is present or where the application is submerged in water.
Stainless Steel 316 – the highest grade of stainless steel that concrete wedge anchors are made from, and are for use in submerged applications and where some chemicals are present, such as chlorine in and around swimming pools.
Concrete wedge anchors are made from a single bar of steel that is threaded on one end, and the other end is necked down with a permanently attached clip. They are packaged with the correct-sized nut and washer.
Concrete wedge anchors come in nine different diameters ranging from 1/4” to 1-1/4”.
Each diameter of concrete wedge anchor is available in different lengths from 1-3/4” in the 1/4” diameter to 12” long in all diameters larger than 1/2”.
The diameter of concrete wedge anchor to use for any particular application depends on the weight of the object being fastened, on the diameter of the hole size in the object being fastened, and on any specifications of diameter recommended by an engineer. The rule of thumb is that the larger the diameter than the better the holding values.
Holding values for Concrete Fastening Systems, Inc. wedge anchor can be found at technical specifications for wedge anchors
The length of concrete wedge anchor to use is based on the thickness of the material being fastened plus the embedment depth of the concrete wedge anchor into the concrete. Each diameter of concrete wedge anchor has a minimum embedment depth that the anchor must be inserted into the concrete for it to obtain minimum holding values. Adding the minimum embedment of the diameter of concrete wedge anchor being used to the thickness of the material being fastened plus the thickness of the nut and washer will give the minimum length of concrete wedge anchor that should be used. Minimum embedment depths for each diameter of concrete wedge anchor are listed below:
|Wedge Anchor Diameter||Minimum Embedment|
The diameter of the hole to drill for a concrete wedge anchor is equal to the diameter of the concrete wedge anchor being installed. A 5/8” concrete wedge anchor requires a 5/8” hole to be drilled into the concrete.
The hole in the concrete needs to be drilled a minimum of 1/2” deeper than the concrete wedge anchor will penetrate into the concrete. This extra space is required to make sure that the concrete wedge anchor does not bottom out in the hole before reaching the intended embedment depth, and also allows for any dust that may be created during the installation to fall out of the way.
As with any anchoring project, it is important to keep safety in mind and follow instructions carefully. Always remember to wear safety goggles, handle all tools with extra care and follow all technical specifications. This article is meant to serve only as a basic explanation of concrete fasteners. Always refer to manufacturer's instructions or consult a contracting expert during any anchoring project.