Australasian Mining Review
Issue link: http://ebook.aprs.com.au/i/26056
6 M Many of the practices outlined and recommended in this article can be regarded as common-sense for any mine operator looking to maximise equipment utilisation and life, writes Paul Comninos. ost mine operators in Australia would now be aware of the tyre supply crisis which is having a dramatic effect on the supply of tyres for both original equipment manufacturers (OEMs) and end users; this issue was outlined in considerable detail over the past 12 months. Recognising that it is a global problem which is not going to go away in the medium term, it is essential that mine operators take steps to manage their tyre use and quickly develop processes to maximise tyre life. The alternative is standing down equipment if no replacement tyres can be sourced. Most mining operations already have personnel who are dedicated to standard tyre maintenance practices, for example correct pressure maintenance and tyre rotations. However, they are often not in a position to influence daily production practices, which have a far greater effect on the consumption of tyres. To maximise returns on tyre investment, and thus minimise the impact of tyre shortage, the mindset of tyre preservation now needs to permeate all levels on the minesite, from middle management to mine planners to truck and loader operators. For example, changing a set of rear tyres on a dump truck can take a better part of a shift; thus any gains in production from assigning an operator to a truck rather than a grader, would be lost by the truck sitting in the workshop due to a tyre rock cut. Furthermore, to ensure that tyres are properly matched, not only does the damaged tyre have to be replaced, but also any accompanying dual tyres. Potentially, that could be up to four new tyres from what is a diminishing stock. A succession of three or four trucks with rock cuts can rapidly drain tyre stock levels on site – not to mention lose production time. There are two key approaches to increasing tyre life: 1. Using Existing Potential: Ensuring you fully utilise the potential of your tyres by doing everything possible within your existing operation to reduce cut-damaged scrap and increase the number of worn out tyres. 2. Increasing Potential Life: Upgrading and improving your existing operation or tyre specification to further improve tread utilisation. For example, where the tyre is previously considered as worn out at 85 per cent tread wear, aim for 95 per cent tread wear. Combining these two approaches will give you maximum tyre life. Let’s look at each in more detail. Using existing potential Again, we can break down this approach to a number of critical factors, which include: 1. Reducing cut damage. 2. Repairing cut-damaged tyres. 3. Operating tyres within their capabilities. Reducing cut damage There are four key steps you can take to minimise cut damage to your tyres – probably the single biggest cause of early tyre failure. These are: 1. Clear loading surface: A clear loading surface means no rocks, stones or other sharp objects in your loading area, where your trucks and loaders are manoeuvring and there are added stresses and shockloads on tyres. Steps to ensure a clear loading surface include: • Using a dedicated grader or dozer to keep the loading area clean of spilt rocks and rubble at all times. Assign an operator to a clean up machine before adding a dump truck. • Improving material fragmentation, with the aim of achieving smaller, better-fragmented materials, which will reduce the risk of cuts. • Training your loader or shovel operators in good target loading practices, to minimise spillage of rocks. • Training your truck drivers in good truck positioning practices to ensure ideal placement for loading operations, again to minimise spillage. • Maintaining good drainage around the loading area; puddles can hide sharp, tyre- killing rocks, while slippery, wet conditions greatly increase the risk of tyre damage. 2. Eliminate spillage on haul roads: Rocks spilt on haul roads are another frequent cause of truck tyre damage. Managing your tyres during the supply crisis