The CONFAST® brand of concrete expansion fasteners are available in twelve various types. Some can be used in most masonry base materials, such as concrete, brick, and block. Other concrete expansion fasteners can be used only in solid concrete, and should never be used in hollow block or brick.
Expansion anchors derive their holding values by creating an outward force to the base material. This outward force creates friction, which will then create the holding values for the anchor.
All expansion type of concrete fasteners/anchors have holding values that are directly related to the diameter, depth of embedment and the strength or PSI of the base material.
For example, all 3/8" diameter anchors embedded in the same exact concrete to the same depth will provide similar holding values. If more holding value is required for a specific application, then a larger diameter and deeper embedment is required.
Each type of expansion type concrete anchor/fastener has its own features and benefits. There is no best anchor because each anchor may provide certain benefits for specific applications that another may not provide. Here are some difference and features:
Wedge Anchors, Drop-In Anchors, Split Drive, and Strike Anchors should be used only in solid concrete, and should never be used in hollow block or brick.
Machine Screw Anchors, Single Expansion Anchors, and Double Expansion Anchors can be used in conjunction with bolts that have national coarse threads.
Lag Shields and Leadwood Screw anchors require the use of screws with lag threads or sheet metal threads
The Split Drive, Hammer Drive, and Nylon Nail-it are more of a permanent fastener because once set in the base material they are tamper-resistant and very difficult to remove.
Sleeve Anchors come in a variety of head styles, are packaged complete, and can be used in most masonry material.
All the CONFAST® brand expansion fasteners/anchors require that a specific hole diameter is drilled in the base material. The diameter of the hole is critical for the anchor to achieve minimum holding values. All holes must be drilled using a hammer drill; never use a straight rotation type drill. A carbide bit must be used in the hammer drill, and the bit must meet ANSI standards. ANSI standards ensure that the bit matches the tolerance required for all expansion type anchors.