Rock Bolts – Friction Bolt
|Yield Strength||345MPa / 120kN||445MPa / 160kN|
|Tensile Strength||460MPa / 165kN||510MPa / 180kN|
|Friction Bolt Diameter||47mm|
|Hole Diameter Range||43mm min./45.5mm max.|
|Mass per Metre||2.79kg|
|Cross Sectional Area||355mm²|
- The DSI Underground Friction Bolt is manufactured from high strength steel tube which has a slot along its entire length. A ring, or collar, is welded on the outer end to hold a domed plate to the rock surface.
- The 47mm Friction Bolt is suitable for installation with hand held rock drills (stoppers/drifters).
- Friction bolts can be load tested by fitting a special ring to the bolt prior to its installation. Pull tests can then be conducted with a hollow ram hydraulic jack.
- Further corrosion protection can be provided by hot dip galvanizing.
Installation Guide Lines
- The hole length should be longer than the bolt, nominally 150mm, to allow for any rock fretting during installation.
- The friction bolt is inserted into the hole. The driving dolly is fitted into the rock drill’s chuck and then the bolt (with accessories) is placed onto the dolly.
- Using full percussion and thrust the bolt is fully driven into the hole until the domed plate is firmly against the rock surface. Care should be taken to ensure the rock drill’s feed/thrust is in the same orientation as the hole or the bolt may be bent during installation.
Standard Lengths & Packaging
- Standard bolt lengths include 450mm long and from 600mm to 2400mm in 300mm increments.
- Non-standard lengths are available on application.
- Friction Bolts are supplied in standard packs of 150 bolts (39mm & 47mm) and 300 bolts (33mm).
Published: September 2011
All dimensions, weights, quantities and specifications are those applicable at the time of publication and may be amended from time to time.