General Features

• Double ended bolts are generally used with expansion shells and post grouted with cementitious grouts.
• The double ended bolt utilises, and is compatible with, DSI Arnall’s expansion shells which provide:
  • An up the hole point anchor.
  • Centralisation of the bolt on the up hole end.
  • Pre-Tensioning of the bolt.
• Refer to Section B4.9 for details of the expansion shell range.
• A drive nut is fitted to allow initial setting of the expansion shell.
• The thread’s strength is nominally equal to the column strength of the bar.
• Corrosion protection may be provided by hot dip galvanizing (refer to Section G).
• Alternative coatings are available by negotiation.
• Double ended bolts are often used as tie rods with rib supports (arches) and supplied with two plain nuts.

Installation Guidelines

• It is imperative that the hole diameter suits the expansion shell to be used.
• The drilled hole length must be longer than the bolt by approximately 50mm.
• Appropriate components are fitted to the bolt. The expansion shell is screwed onto the bolt until the bolt thread just protrudes through the expansion shell plug.
• After placing the bolt in the hole to its full length, the bolt nut is rotated to set the shell and tension the bolt.

Standard Lengths & Packaging

• Standard bolt lengths range from 600 to 2400mm in increments of 300mm.
• Non-standard requirements are available by negotiation.
• Bolts are packaged in bundles with threads protected by heavy duty polyethylene bags.
• Bolt fittings, such as nuts, anti-friction washers and dome balls, are supplied fitted to rock bolts in the configuration 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.