The WA Department of Mines, Industry Regulation and Safety recently issued a safety bulletin following reports of potentially serious incidents involving graders when either a front steering wheel or a driving wheel experienced catastrophic failure of its stub axle, resulting in the wheel suddenly detaching during operation.
There have been a number of recent incidents including seven steering wheels detaching as well as a driving wheel detaching.
While these incidents were injury free, in all cases there was temporary loss of control of the machine and the detached wheel rolled away in an uncontrolled manner.
The modes of failure, the physical root causes and contributory factors in all these incidents were found to be similar.
The safety bulletin said there were a number of associated hazards:
There were a number of contributing factors to these incidents, including:
The bulletin subsequently recommended a number of required actions: