CONFAST Single Expansion Anchor

Concrete Fastening Systems, Inc. introduces the CONFAST Single Expansion Anchor which is designed for anchoring into concrete, brick or block base material.

Concrete Fastening Systems, Inc. introduces the CONFAST Single Expansion Anchor, which is now available through direct purchase. The 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 1/4-inch to 3/4-inch. 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.

“CONFAST Single Expansion Anchors can now be purchased online. With free shipping on orders of $25 or more, and all sizes in stock for immediate shipment, we save our customers both time and money over buying concrete fasteners through a distributor,” explained Bob Carlisle, president and founder of Concrete Fastening Systems, Inc. “Our CONFAST brand of fasteners are of construction grade and heavy duty quality.”

Technical Specifications for Single Expansion Anchors

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 all of 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 ten (10) anchor diameters for spacing between anchors and five (5) anchor diameters from an unsupported edge.

When vibration or sudden impact is part of the load conditions, the spacing should be increased.

Technical Information:

  • Ultimate Load Values in 2000 PSI Concrete
  • Size Minimum Embedment Max. Torque Drill Bit Pull-Out (lbs.)
  • 1/4” 1-3/8" 5 ft. lbs. 1/2" 532
  • 5/16” 1-1/2" 7 ft. lbs. 5/8" 847
  • 3/8” 2" 10 ft. lbs. 3/4" 1023
  • 1/2” 2-1/2" 20 ft. lbs. 7/8" 1942
  • 5/8” 2-5/8" 30 ft. lbs. 1" 3217
  • 3/4” 3-15/16" 40 ft. lbs. 1-1/4" 4487
  • 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 percent is generally accepted as a safe working load. Reference should be made to applicable codes for the specific working environment.