Australasian Mining Review
Issue link: http://ebook.aprs.com.au/i/26056
7 [Tyres} Steps to help eliminate spillage on haul roads include: • Targeted loading on the part of your shovel and loader operators, to ensure the load is fully within the truck body, and properly distributed to minimise the chance of spills. • On corners, either instructing your drivers to reduce speed or incorporating superelevation to ensure the truck and its load remains properly balanced at all times. • Ensuring that truck loads are positioned to minimise spillages on the haul road during gear changes. • Eliminating soft spots and rough patches of haul road, where loads can bounce out and/ or tyres can be damaged. 3. Control your dump area: The dump area offers further potential for tyre damage from spilt loads and poor operating practice as fully loaded trucks manoeuvre into position. Steps to control your dump area include: • Incorporating dedicated roads in the dump area; instead of allowing trucks to travel anywhere in the dump area, a dedicated road is easier to keep clear of spilt materials and is a far smaller area that needs to be maintained. • Using a dedicated grader or dozer to keep the area clean. • Instructing your drivers to only perform an “L- turn” at the dump area, rather than a U-turn; U-turns produce significant side force loadings on the front tyres, increased tyre wear and higher rates of material spillage (see diagram for correct procedures). • Ensuring good windrow maintenance, to keep dumped material clear of truck tyres. • Eliminating soft spots and rough patches. 4. Minimise operation in wet conditions: Wet conditions pose an extremely high risk of tyre cut damage. Tyres are more prone to cutting when rocks and spilt materials are wet and slippery, while puddles can hide rocks that an operator might otherwise avoid. In addition, operating over a wet surface, exposes the roadbase, and increases the risk of tread cuts. Repairing cut-damaged tyres Repair of cut-damaged tyres is another option for extending tyre life. While a repair can never return the tyre to its original level of structural integrity, it can improve the opportunity for you to safely get close to a full life from a damaged tyre. While it is possible to effectively repair tyres that have been quite badly damaged, timely removal of cut-damaged tyres for repair will ensure you keep repair costs to a minimum, and are able to get maximum life from the repaired tyre. In the case of damage to the tread area, a tyre should be removed for repair when separation on the top belt occurs, or when the belts have been penetrated. Damage to the sidewall area requires removal f or repair once the steel ply is visible. Operating tyres within their capabilities Ensuring your tyres are operated within their capabilities is critical to ensuring maximum tyre life. Apart from cut damage caused by sharp rocks and rubble, heat is the great enemy of tyres. Tyres that are consistently overheated will break down and fail well before their maximum life. In the past, many mining operations have chosen to overwork their tyres, happy to trade off shortened tyre life in return for higher productivity. However, today, with the likelihood of tyre shortages requiring equipment to be stood down, this philosophy needs to be reconsidered. The prime indicator of a tyre’s capability is the TKPH (tonne/kilometres per hour) rating. Each earthmover tyre has a TKPH rating; if it Australasian Mining Review 2011: issue 2.1