Wriggle Bolt

Physical Properties

16mm Bolt	Minimum		Typical
Yield Strength	400MPa	65kN	460MPa	75kN
Ultimate Tensile Strength	590MPa	95kN	645MPa	105kN
Calculated Shear Strength	60kN		70kN
Standard Elongation	17%		22%
Uniform Elongation			12%
Mass Per Metre			1.21kg
Bar Diameter			14.4mm
Cross Sectional Area			160mm²
Bar Straightness to AS 1442-1991
Rolled Thread M16x2.0 Pitch

20mm Bolt	Minimum		Typical
Yield Strength	375MPa	95kN	440MPa	110kN
Ultimate Tensile Strength	540MPa	135kN	680MPa	170kN
Calculated Shear Strength	90kN		110kN
Standard Elongation	19%		22%
Uniform Elongation			12%
Mass Per Metre			1.99kg
Bar Diameter			18mm
Cross Sectional Area			250mm²
Bar Straightness to AS 1442-1991
Rolled Thread M20x2.5 Pitch

General Features

These bolts are manufactured from round bar with "wriggles" on the up hole end which allows a small diameter bolt to mix chemical anchors in standard diameter holes.
The wriggle bolt is an economic alternative when the tensile strength of larger bolts is not required.
The rolled thread strength nominally equals the column strength of the bar.
The Wriggle Bolt is designed to be used with chemical anchors (refer to Section F), but can be effectively used with cementitious grouts.
The Wriggle Bolt has been found to be effective in coal rib stabilization and mesh retention on rock embankments.
The nut fitted to Wriggle Bolts has similar across flats dimensions as nuts fitted to 24mm bolts to utilize standard roof bolt spanners.
Corrosion protection may be provided by hot dip galvanizing (refer to Section G). Alternative coatings are available by negotiation.

nstallation Guidelines

26-28mm hole diameters are preferred for 16mm Wriggle Bolt and 27-29mm for 20mm Wriggle Bolt.
Hole depth is critical. Hole depth should be shorter than the bolt to allow for the height of the washer and nut.
After insertion of the chemical anchors, the bolt is rotated through the anchors while being pushed to the back of the hole. Care should be exercised to ensure the bolt is held axially during installation.
It is important to follow the chemical manufacturer’s recommended mixing and hold times as printed on the chemical anchor cartons. DO NOT OVER-MIX.
For further details regarding installation procedures, refer to DSI’s "Practical Guide to Rock Bolting."

Standard Lengths & Packaging

Standard bolt lengths range from 600 to 3000mm in 300mm increments.
Non-standard requirements are available by negotiation.
Bolts are packaged in bundles with threads protected by heavy duty polyethylene bags.
Bolt fittings, such as nut and anti-friction washer, are normally supplied fitted to wriggle bolts in the configuration as requested.

Notes

Only DSI rock bolt components should be used in order to obtain full performance of the bolt system.
DSI's Mining Products Division is Quality Assured to ISO 9001:2000, Registration No.QAC/R61/0315.

PRINTED December 2006: All dimensions, weights, quantities and specifications are those applicable at the time of publication and may be amended from time to time.