Coal being added to a coal hill.

Fibre composite drill rods: an improved sense of direction

Dr Philip Teakle sees composite drilling rods as the future of directional drilling in coal seams.

• 23 August 2006 | Updated 14 October 2011

• Problem
• Solution
• Future

Problem

The mining industry currently uses metal drill rods to house sensors for directional coal seam drilling.  Unfortunately, these rods interfere with electrical, magnetic, electromagnetic and gamma ray analysis of material surrounding the borehole. 

Strength and toxicity of the metals used are also an issue.

Fibre composite specialist Dr Philip Teakle, Project Leader (Fibre Composites), Minerals Down Under, Queensland Centre for Advanced Technologies (QCAT) believes that he has found a solution to this problem.

Solution

Drill rods made from a fibre composite can offer improved sensing during the drilling process. 

They can also potentially improve directional accuracy and provide geophysical information that is currently unavailable during the drilling process, thus reducing non-productive time and improving gas drainage.

Fibre reinforced composites are made from fine high-strength filaments bound in a polymeric matrix. Most filaments are glass, aramid (Kevlar) or carbon. Most matrices are epoxy, vinyl ester or polyester.

Fibre-reinforced composites have very high strength- and stiffness-to-weight ratios when compared with metallic materials. Reinforcing fibres can also be aligned with the load.

Most fibre composites are not susceptible to corrosion and do not interfere with sensing equipment. 

The new composite drill rods could lead to significant cost and productivity savings for mining companies.

Future

Design and testing of prototype drill rods will proceed with commercial partners.

Other possible applications are:

• coil drilling - in which rods are replaced by a coil of continuous tubing
• making not only sensor housings but the entire drill string from composites.

Learn more about Transforming the future mine.