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Technical Information:
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 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.
Double Expansion Anchor concrete anchor/fastener -
Approvals:
Meets Zamak 5 Zinc Alloy: A.S.T.M. Specification
24 (AC41A) and S.A.E. 925.
Double Expansion Anchor concrete anchor/fastener -
Applications:
Medium duty in concrete, block and brick.
Double Expansion Anchor concrete anchor/fastener -
Installation:
(1) Drill hole of recommended diameter, see chart below, into
the base material to a depth equal to, or slightly deeper
than the length of the expansion anchor. Clean out the hole
of all dust and cuttings. (2) Place the Double Expansion anchor,
nut end first, into the hole. The top end of the anchor should
be flush or slightly below the base material surface. (3)
Place the object to be fastened over the anchor in the base
material and bolt in to place.
Double Expansion Anchor concrete anchor/fastener -
Anchor
Spacing:
The forces on a Double expansion anchor are transferred
to the material that it is installed in. If the anchors are
installed too close together, it can cause an interaction
of the forces, thus reducing the holding power of the anchor.
As a rule of thumb, the expansion 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 are part of the load
condition anchor spacing should be increased.
Double Expansion Anchor concrete anchor/fastener -
Bolt
Length:
Thickness of material to be fastened plus length
of anchor equals bolt length.
Double Expansion Anchor concrete anchor/fastener -
Technical
Data
| Anchor Size |
Anchor Length |
Hole Size |
Bolt Dia. |
Pull-Out 5000 psi concrete |
| 1/4" |
1-3/8" |
1/2" |
1/4" |
1100 lb. |
| 5/16" |
1-3/4" |
3/4" |
5/16" |
1450 lb. |
| 3/8" |
2-1/16" |
3/4 |
3/8" |
1750 lb. |
| 1/2" |
2-1/2" |
7/8" |
1/2" |
2200 lb. |
| 5/8" |
3" |
1" |
5/8" |
6500 lb. |
| 3/4" |
4" |
1-1/4" |
3/4" |
4600 lb. |
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% is generally accepted as a safe working load. Reference
should be made to applicable codes for the specific working
ratio. Minimum embedment for satisfactory anchor performance
is 4-1/2 bolt diameters. Deeper embedments will yield higher
tension and shear capacity.
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