Published in June 2009 Australian Longwall Magazine
The Baal Bone team has invented a Heavy Equipment Tow Hitch that helps mitigate the risk of moving machinery around through improved control of heavy loads, easier manoeuvring and decreasing personnel exposed to heavy machinery.
In all longwall mines, heavy equipment such as shuttle cars are regularly transported underground, towed by diesel-powered equipment. The risk to staff operating around equipment is high in the confined space and with the poor visibility.
The energy required to move the machinery poses hazards currently managed by externally powered brakes and by effectively controlling car movement during towing.
Baal Bone believed the fit-for-purpose draw bars used were not always an effective way of moving equipment, with the shunting into cut-throughs and headings continually damaging the draw bar and machinery.
For Baal Bone, chains or commercially available tow devices simply didn’t cut it.
“They did not provide the level of control or reliability that the mine required,” the mine said in its submission to the 2009 NSW Minerals Council Occupational Health and Safety Innovation Awards.
The mine’s dissatisfaction inspired it to develop a multi-purpose Heavy Vehicle Tow Hitch.
“The concept of using a specialised heavy-duty tow attachment that is capable of articulation in two planes is not new to the mining industry,” Baal Bone said, adding heavy equipment already included an articulated tow hitch.
However, Baal Bone wanted to take the hitch one step further.
The team’s invention used several simple and commonly-used engineering concepts in a new format.
The team recycled a redundant roof support transporting trailer and the articulation joint previously used between the engine module and the trailer.
The mine arranged with an accredited engineered workshop to attach the articulation joint to the Eimco LHD QDS plate and manufacture tow plates for fitment to shuttle cars, ratio feeders and any other large and heavy equipment that needed towing.
The three primary components of the system are the Quick Detach System (QDS) that allows the easy and quick attachment of the tow hitch to the prime mover – in Baal Bone’s case, usually a Eimco 130 LHD; the correctly rated articulation joint that allows the controlled towing of wheeled heavy equipment around the mine; and the simple tow plate which is easily fitted to each piece of equipment that requires movement, enabling the attachment of the tow hitch.
“These three primary components are married together to provide a flexible and unique tool that can be used to safely move most of the commonly-used wheeled heavy equipment around the mine,” Baal Bone said.
The innovation features turnbuckles that are used to stabilise the hitch while it is being attached to the equipment being towed, effectively eliminating heavy lifting and removing the operators from any pinch points while the hitch is being attached to the load.
“The flexibility of the system has huge advantages over one-off designed machinery that is only capable of moving one specific type of equipment,” the mine said.
The results of the innovation were quickly evident. Personnel have improved control of heavy tow loads, and they are easily able to manoeuvre shuttle cars and other long loads and shunt into cut-throughs and headings.
The innovation also allows one-man operations to tow a shuttle car. Plus, there are no concerns about losing two pins. All these benefits meant the invention was readily accepted by the workforce.
“The risk of an accident caused by an uncontrolled movement of a towed load is reduced,” the mine said.
“Damage to machinery has been eliminated and the cost of labour has been reduced.”
While Baal Bone used recycled parts to make the hitch and therefore minimised costs, it said the cost of manufacturing the device from scratch would be $40,000.
