Building the last line of defence against dangerous coal bursts

Full article issued by the ARC Industrial Transformation Research Hub for Nanoscience-based Construction Material Manufacturing (the Nanocomm Hub)

Nanocomm Hub Chief Investigators, Associate Professor Ting Ren and Professor Alex Remennikov, have been working to innovate a new protective system for continuous miners in underground coal mines. The two researchers, both from the University of Wollongong, have collaborated with industry partner Peter Holt of Ironclad Mining Machinery to develop a system of energy absorbing panels that can be readily assembled underground.

The project is intended to meet new industry standards that were put in place following a 2014 New South Wales coal mining tragedy in which two men died 500 metres underground. The men had been operating a continuous mining machine when hundreds of tonnes of coal collapsed on them. This tragedy sparked an investigation that determined that existing protective systems were woefully inadequate, prompting tighter safety regulations. 

'We wanted to design a new protective system that could be installed on continuous miners as the last line of defence after all other mitigating measures fail,' explained Associate Professor Ren. 'Our aim was to protect people working on these machines against the hazard of coal bursts while building roadways in highly stressed and gassy coal seams.'

They built a prototype with a number of energy-absorbing honeycomb panels made of very thin steel, with a height of 1.5 metres to protect the full body of a miner. A cover plate is robotically welded to the honeycomb core, with each panel requiring several hundred welds. Through impact testing, the team assessed the energy-absorbing capacity of the panels and found that, even with 600 kg of coal dropped from a 5-metre height at a velocity of 9 m/s, the panels could absorb a significant amount of energy without disintegration.

The team now plan to take their prototype to coal industry operators and coal industry equipment designers to generate interest in its further development.

 

Image Credit: Xiaohan Yang.