Beware of the bulge

AN unusual bulge on a pneumatic tyre’s sidewall is an early sign of a looming catastrophic tyre failure, according to a Queensland safety alert that sheds light on an incident that put two Peak Downs maintenance workers in hospital earlier this year.
Beware of the bulge Beware of the bulge Beware of the bulge Beware of the bulge Beware of the bulge


Blair Price

In February the two workers were taken to Moranbah hospital to receive treatment for minor abrasions after a tyre blow-out on a parked water truck, while a third worker was also impacted by this incident according to police at the time.

While the Queensland Mines Inspectorate does not reveal specific mines in its safety reporting, it provided findings from this incident last week in a safety alert.

The inspectorate said a mine maintenance crew were preparing to start chassis repairs on a Cat 773 water cart which was out of service for several days.

The bulk water tank was removed and the three workers were conducting a necessary job safety analysis.

“They noticed a small bulge, about the size of a fist, on the outer sidewall of the position five tyre facing the position six tyre and recorded this on the JSA form,” the inspectorate said.

“This was to be raised with the tyre fitters who were en route to remove the position five and six tyres so the maintenance crew had access to the chassis for repairs.”

The two workers that were later hospitalised stood directly behind the bulging tyre while a third worker had walked past them to look at another nearby tyre at the time of the incident.

“A blast suddenly engulfed the workers in a cloud of dust and loose gravel as the tyre sidewall failed catastrophically,” the inspectorate said.

“The two workers at the rear were showered with hard-stand gravel and fine dust while the third worker was hit with the air blast.

“The first responders to the incident treated it as a tyre fire, which required experienced tyre fitters to assess the situation before an examination of the tyre was performed.”

The cause of the incident was a “latent defect” in the tyre which resulted in the sidewall failure and the blast of compressed air.

Worryingly, this incident occurred while the tyre was not under any structural load and while it was not at an operating temperature.

The blown out tyre had no visible signs of being run while flat or with low air pressure either.

“Those who noticed the bulge on the sidewall did not recognise it as the start of a potentially catastrophic sidewall failure,” the inspectorate said.

“This incident reinforces the need for minesites to assess the adequacy of their processes for managing tyre defects, in particular sidewall bulges and deformation, and for effectively controlling worker’s exposure to such hazards.”

Most read Archive



Most read Archive