Single Expansion Anchor

CONFAST single expansion anchors are designed for anchoring into concrete, brick or block base material. This light to medium-duty fastener is manufactured from Zamac, a non-rusting material, and is available in diameters ranging from ¼ to ¾ in. The single expansion anchor is set flush with the base material and inserting a machine-threaded bolt into the anchor expands it against the concrete at a single point.

Considerations when using the single expansion anchor include anchor diameter, bolt diameter, and required hole size. The single expansion anchor is an effective fastener when working with soft masonry or base materials of questionable strength. Anchor size refers to the diameter of the machine bolt/screw used to expand this anchor. Once these factors have been determined, you can find the expected holding values in the technical information below:

Length
To determine the length of machine bolt required, add the thickness of the material to be fastened plus the length of the single expansion anchor.

Spacing
The forces on a Single Expansion Anchor are transferred to the material in which it is installed. If the anchors are installed too close together, it can cause an interaction of the forces, thus reducing the holding power. As a rule of thumb, the expansion anchor industry has established a minimum standard of 10 anchor diameters for spacing between anchors and 5 anchor diameters from an unsupported edge. When vibration or sudden impact is part of the load conditions, the spacing should be increased.