Double Expansion Anchors
The double expansion anchor works well in soft masonry and mediums of questionable strength. As the "double" sets, the two opposing wedges pull towards each other, expanding the full length of the anchor body. Eliminates high stress points detrimental in fastening into materials of medium hardness, has high gripping power and expands fully.
Double Expansion Anchor Features
- Can be used in concrete, brick, block or stone.
- Use with machine screw bolt or screw.
- Dual expansion develops greater contact with walls of hole.
- Ideal for sheer loads or where bolt is subjected to side pressure or vibration.
Double Expansion Anchor Description
The double expansion anchor consists of a nut, a cone and a tubular shield preassembled as a single unit. The two-piece tubular shield is bound together with two spring bands. It contains a wedge shaped nut at one end and a wedge shaped hollow cone at the other end. Integral lugs on the nut and cone keep the wedges from turning in the tubular shield during expansion. The anchors are of precision die-cast zinc alloy commonly known as Zamak 5. The expansion action at both ends of the shield distributes the anchored load throughout the length of the shield. This expansion anchor is recommended for shear loads or where the bolt is subjected to side pressure or vibration. Once fastened, the object may be unbolted, removed, and/or fastened.
Commonly Called
Double expansion shield, keystone double, double thunderloc, double, DMSA, machine screw anchor.
Applications for Double Expansion Anchors
Medium to heavy duty in concrete, block, brick and stone.
Deciding Length of bolt needed for Double Expansion Anchors
Thickness of material to be fastened plus length of anchor equals bolt length.