Safety and efficiency of running your tires go hand in hand. With that in mind we are always looking for ways to help our customers get more life out of their tires and do it as safe as they can. Below is a safety bulletin we found that was published by the Queensland Government – Department of Natural Resources and Mines. We hope you find this information helpful!

The mining industry is currently facing a worldwide shortage of Large Earth Moving Tyres.

Due to this shortage it is inevitable that operating companies will be seeking to maximise tyre life and to review tyre
management and maintenance practices. This maximisation is not unreasonable but it will be seen to leave tyres in
service that, before the shortage, would have “normally” been taken out of service based on appearance rather than actual
condition. Therefore these tyres that were previously taken out of service may have still been ‘fit for purpose’ and may
not have achieved their full potential service life. This change in our industry is a significant change and will throw up
challenges that need to be effectively managed. The application of change management practices should form part of the
strategy to address this emerging issue.

A move to extending tyre life can be safely managed if appropriate resources and knowledge are applied.
Issues to Consider:

A risk assessment process must be applied as a management tool to cater for this change in the industry. The
process should ensure that the current controls are strengthened and new controls identified.

Tyre wear and condition should not exceed the discard criteria as specified by the manufacturers.

Appropriately trained, competent and knowledgeable people are required to inspect and make decisions on
tyre condition. As the move to extend tyre life continues, the current inspection regimes for what was
considered “normal” may need to be more intensive (e.g. daily as against weekly), and the level of expertise
engaged for the inspections may need to be increased accordingly. (Refer to CMSH Regulation section 71
(a) (b) (i), MQSH Regulation section 108) It is beneficial to expand detailed training in tyre condition
inspection to operators.

Inspection reports and pressure checks need to be not just done, but also interpreted by skilled people so that
a meaningful outcome can be derived and implemented. Inspection for the sake of inspection will not
contribute to extending tyre life.

Maintenance of suspension and steering components of haul truck and loader fleets will play an important
role in any strategy to safely extend tyre life and must assume high importance.

A strategy of short and long runs to reduce tyre overheating and possible ply separation failure.

Adoption of a temperature monitoring regime using non intrusive methods such as thermal imaging or heat
measuring guns.

Good haul road design will need to be strictly adhered to and take into account such factors as:

o Eliminating or minimising reverse camber corners.
o Haul road grade, curvature and undulation.
o Tyre specification and suitability for the hauling route.
o Appropriate road construction materials and running surface material.
o Minimising spillage through design.

Haul road maintenance can and will play an important role in safely extending tyre life by ensuring that:

o Spillage is dealt with quickly.
o Haul road running surfaces are regularly graded.
o An effective surface water management program is in place.

Loading and dumping practices such as overloading, poorly maintained loading and dumping pads, and
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reversing onto production material at loading faces all have a detrimental effect on tyre life and will see the
tyre removed earlier from service due to damage rather than full service life wear. Regular ‘dozing of these
areas will have a huge positive impact.

Adopting a dump short and dozer push method on dumps will help in avoiding ‘cut damage’ to tyres,
especially in wet conditions.

Education of operators on what is acceptable tyre condition is a priority, especially considering that, unlike a
passenger car or light truck, tyre baldness is not necessarily considered to be a discard criteria by the tyre
manufacturer. Most manufacturers will recommend repositioning of the worn tyre to position 4 or 5 (inner
tyres of the rear duals) and increased monitoring until the discard criteria as specified by the OEM are
reached. If this strategy is adopted, the level of monitoring needs to be substantially increased and those
carrying out the monitoring must have the requisite knowledge to make the correct informed decision
regarding changing tyre position and ultimate discard.

Tighter control of maintaining tread depth consistency across dual sets of wheels.

Operator education on driving practices to enhance tyre life should be considered, as it is probably the frontline
weapon in meeting this forthcoming challenge to our industry. Operators are in the best position to
extend tyre life.

Consideration of tyre repair to sidewall or tread lugs at an earlier stage of damage than is often undertaken at
present. Use of knowledgeable repairers is essential to inspect and report expected tyre life after repair and
heed recommendations regarding the placement of the tyre on the truck (e.g. position 4 as opposed to
position 1).

As can be seen from the above issues, and not all have been discussed here, effective tyre life management requires
many inputs and both the production and maintenance streams have important roles to play in safely extending tyre life
in our operations.

Running tyres to destruction should not be an acceptable strategy to extend tyre life.

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