Confast Drop-In Anchors Now Available for Suspending Electrical Cable Trays, HVAC Ductwork and Fire Sprinkler Pipe, Heads and More
By: CONFAST Concrete Fasteners
There are numerous technical specifications that must be considered when using Concrete Drop-in Anchors. Considerations include diameter and material type, internal thread length, minimum edge distance and required hole size.
The Concrete Drop-in Anchor is a great fastener option when working with flush mounting applications. The size of the Drop-in Anchor refers to the diameter of the standard UNC threaded rod or bolt to be used with this fastener. Once all these factors have been determined, you can find the expected holding values in the technical information on our website
When setting the anchor flush with the base material: To determine the minimum bolt length required, add the internal thread length of the anchor, plus the thickness of the material to be fastened, plus the thickness of any washer to be used.
When setting the anchor deeper into the concrete:
Determine the minimum bolt length above and add the additional depth to the minimum anchor length.
The forces on a Drop-in Anchor are transferred to the material in which it is installed. If the anchors are installed to close together, it can cause an interaction of the forces, thus reducing their holding power. Minimum anchor spacing and minimum edge distances for the drop-in anchor are as follows:
Values shown are average ultimate values and are offered only as a guide and are not guaranteed. A safety factor of 4:1 or 25% is generally accepted as a safe working load. Reference should be made to applicable codes for the specific working ratio. Minimum embedment for satisfactory anchor performance is 4-1/2 bolt diameters. Deeper embedments will yield higher tension and shear capacity.