Threaded vs Expansion
Easy Install, Removal / Reuse
Screwbolts are incredibly easy to install. Being fully threaded also allows them to be removed and reused with ease. Sleeve anchors are a expansion anchor, this means that one installed they cannot be removed or reused. Removal involves grinding the anchor flush with the substrate surface, leaving an unsightly steel section in the concrete to rust.
Strength, Stress and Safety
Screwbolts, being a 'screw anchor' and not an 'expansion anchor', means they cause no stress on the substrate when anchored. This makes them an ideal fixing for close to edge applications. Where as expansion anchors fix to the substrate by friction force to the wall of a pre-drilled hole. The force of the expansion needed for anchoring the bolt in the substrate, may cause cracking when close to the edge of concrete or other materials. Sleeve anchors have one point of expansion along the bolts shaft, meaning only a small area actually provides the load capacity. Screwbolts on the other hand, have a thread running the entire embedment depth of the shaft, thus providing a much higher load strength spread across a larger surface area.
High Strength vs Mild Steel
Screwbolts are made from high strength carbon steel. This makes them a perfect candidate for structural applications. High tensile steel accompanied by a threaded design, allows a Screwbolt to have a higher load capacity than an expansion anchor with an equivalent diameter.
Sleeve Anchor steel grade is 5.8 which may not always be acceptable for structural applications. Higher loads can be achieved by using Screwbolts.
Head Marking for Identification
Screwbolts, being a one piece design, are able to have dimensions stamped on to the head of the bolt, both diameter and length, no matter what head profile is chosen. This allows anyone to quickly and easily identify that the correct bolt was used in a certain application post install.
The most common Sleeve Anchors are hex head. Hex head Sleeve Anchors, being a thread through nut design, do not have the ability to have dimensions visible once installed. This means that identifying the depth of the bolt is impossible once the bolt has been fixed.
Screwbolts have a range of head profiles to choose from, such as Hex, Pan and Countersunk head profiles. These one piece head profiles leave an aesthetically pleasing finish, and a choice of head profile to suit most high exposure applications. Sleeve anchors on the other hand, being a 'thread through nut' design, leave an unsightly head finish once fixed.