The coil threaded, multi-set drop in anchor is designed specifically for use with a coil-threaded rod, commonly used in bridge forming construction. The coil threaded version of the multi-set drop in anchor differs from the standard multi-set drop-in anchor due to the threads that the anchor will accept.
Concrete is the only base material that should be used with a multi-set coil threaded drop-in anchor. They are not designed for use in brick or block base material.
The coil threaded version is only available in the zinc plated carbon steel version and in two diameters- 1/2" and 3/4" since coil threaded products are not used in any other diameters.
The depth of the threads in the multi-set threaded drop-in anchor is longer than the threads on the standard multi-set drop-in anchors of the same diameter. The 1/2" coil threaded version has 3/4" of threads and the 3/4" had 1-1/4" of threads to accommodate the thicker, coarse coil threads.
The minimum embedment for both diameters of this type of anchor is equal to the anchor length. The anchor must be flush with the surface of the concrete to ensure that minimum embedment requirements are met. The 1/2" coil threaded drop-in has a minimum embedment of 2" and the 3/4" has a minimum embedment of 3-3/16".
The hole diameter to be drilled into the concrete is equal to the outside diameter of the anchor. The 1/2" diameter requires a 5/8" hole; the 3/4" requires a 1" hole. The hole in the concrete must be drilled using a hammer drill and the correct carbide bit to ensure the proper tolerance.
The coil threaded multi-set drop-in anchor is an internally expanded concrete anchor that has to be expanded in the concrete with a setting tool. The setting tool is designed to fully expand the anchor in order to meet the stated holding values. The lip of the setting tool must meet the lip of the anchor to ensure that the coil threaded multi-set drop-in anchor is fully expanded.
1. Drill the correct diameter and depth of the hole in the concrete using a hammer drill and carbide tipped bit that meets ANSI standard B212.15-1994.
2. Use compressed air, vacuum, or wire brush to clean the hole of all debris and dust created during the drilling process.
3. Insert the coil threaded multi-set drop-in anchor into the hole in the concrete. Use a hammer to tap the anchor until flush with the surface of the concrete.
4. Use the correct sized setting tool and place the setting tool into the threaded portion of the anchor. Strike the end of the setting tool with a hammer until the lip of the tool meets the lip of the anchor.
5. The coil threaded multi-set drop-in anchor should now be properly expanded.
The multi-set coil threaded drop-in anchors are commonly used in bridge construction and can only be used in the concrete base material. It is important to follow all installation instructions to ensure proper and safe usage of these concrete anchors.
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.