Also referred to as two-step bolts or anchor bolts, Sleeve Anchors are a style of fastener that fixes items to concrete or masonry. They’re commonly used to attach two or more concrete structures or to connect objects including a shelf to a brick wall.
This anchor includes a solid metal screw or stud that features a cone-shaped tip that flares out to the sides. A metal sleeve wraps around the outside of the screw causing the tip to extend out the sleeve’s end. A washer and nut are on the top of the anchor so that an installer can adjust and install it.
Sleeve Anchors serve as a light or heavy-duty fastening device. They are used to fix an assortment of base materials including concrete, brick and block. The design of the anchor is the determining factor as to where they can be used. Sleeve anchors are made of stainless steel that is ideal for out door, wet applications. They’re also zinc plated varieties for indoor use in dry environments.
There are two types of Sleeve Anchors –- nut driven and flat head.
The nut driven variety is commonly used when extra strength is required. It is more common that the flat head and comes in a number of finishes. Nut driven Sleeve Anchors are appropriate for most types of concrete and masonry. It secures a medium loads in proper applications.
A countersunk sleeve anchor option, the flat head variety is commonly used when fixing to a flush surface. It is ideal for applications where jutting fixtures can cause inconveniences including opening doors or when an attachment can be interrupted and hidden fixing is required.
Flat head anchors are attached in the hole with a suitable screwdriver as opposed to a wrench, which is necessary for nut driven anchors.
Abrafast offers a number of different sleeve anchors. They include:
A threaded bolt and sleeve that is made of 303 or 30e stainless steel, the Kanebridge Flat Head Hex Nut Sleeve Anchor is available in ¼-inch and 3/8-inch diameters and come in various lengths.
When the nut is tightened, the sleeve dilates against the substrate. It is ideal for anchoring windows and doorframes.
Made of 304 grade stainless steel, the MKT Sup-R Sleeve hex Nut has a sleeve length that makes it more forgiving than a wedge anchor. It offers less stress on the substrate and can be used in solid or hollow masonry. Having the ability to work in a bottomless hole, the MKT Sup-R Sleeve requires a hole diameter that equals the diameter of the anchor. It is available with four possible head styles.
It is ideal for attaching ½-inch maximum thickness materials into a 1-1/8-inch minimum embedment. It is ¼-inch in diameter thread stud and requires 18-22-lbs.-ft of torque for proper installation.
The Simpson Sleeve-All Hex Nut is made of carbon steel or stainless steel and includes a carbon steel zinc plated finish. It comes in a range of diameters including ¼-inch, 5/16-inch, 3/8-inch, ½-inch, 5/8-inch, and ¾-inch.
Before starting an installation, consider how many sleeve anchors you require. Too many fixings that are spaced too close together can reduce the holding power. Sleeve anchors should be spaced at a minimum of 10 anchor diameters apart, but place no closer than five diameters from an unsupported edge.
You should increase the spacing when the fastening conditions include vibration or sudden impact. These conditions will lower the interaction of forces created inside the base material.
Installing Sleeve Anchors
Items you’ll need to install a sleeve anchor includes:
- Hammer Drill
- Compressed Air
- Wire Brush
- Sleeve Anchors
- Wrench or Screwdriver
It is friction that assures the proper bond between the fixing and the concrete. So it is essential to get the installation of the sleeve anchor correct.
- Position the material you are anchoring and mark the locations of the anchor holes on the concrete. If there is adequate clearance for drilling a hole, then leave the product in place for more precise positioning.
- Use the hammer drill to drill holes into the concrete at the proper bolt hold locations of the product being fixed.
- The holes need to be the specified diameter of the anchor being used. It should be ½-inch to 1-inch deeper than the expected depth of the fixing. Anchor lengths are measured from underneath the nut and washer to the tip of the stud. (Note: most hammer drills have a depth gauge. If the one you’re using does not, then wrap a piece of tape around the bit at the certified depth length.
- Use compressed air and/or wire brush to clean the hole. This is essential to assure that the anchor will have maximum holding ability and that the sleeve adheres directly to the sides of the hole evenly.
- Position the nut so that it is even with the top of the thread to assure that the threads are not damaged during installation.
- Hold the nut and insert the anchor body through the holes on the product you’re fixing and into the base material.
- Tap the anchor with a hammer until the nut and washer are flush with the fixing.
- Hand-tighten the nut. Once installed with a tool, sleeve anchors can’t be removed. So it is essential that you hand-tighten before using a tool.
- When the position is right, use the wrench or screwdriver to tighten the anchor. Use a wrench to tighten an anchor with a hex or acorn nut and the proper headed screwdriver with the round or flat head anchor. Turn three to five times until the installation torque is reached. Don’t over torque to avoid compromising the fastening value.
Abrafast carries a wide range of fixing anchors. We probably have any fastener you will need regardless of the application. Our staff will be happy to help you select the proper fixer for your particular needs.