Overview
To deliver improved operational efficiencies for one of our client projects, the Emeco Operating System (EOS) team investigated increasing the bucket size for their main production digger. The review was primarily conducted to assist in achieving the project’s increased annual mine plan targets, but also resulted in significant potential savings.

Challenge
By increasing the bucket size of the EX2600 digger there was a risk that the bucket weight could be overloaded making it unstable to operate and resulting in damage to the machine. The situation therefore called for a review of the machine specifications and some careful mathematics.

The current bucket capacity of the EX2600 digger is 15m3. On site, this machine historically achieved a bucket fill factor of less than 80 per cent. Machine specifications indicate the bucket has a maximum lifting capacity of 38.4t, based on a maximum loading radius of 12m and a lifting height of 4m above the bench, which is appropriate for a 100t truck. The 38.4t lifting capacity utilises 87 per cent of the full machine’s hydraulic capacity and could not be exceeded

To upgrade to a standard 17m3 bucket, weighing 15.6t and allowing 4.4t for bucket armouring, gives a maximum bucket payload of 34.4t. If the fill factor were to increase to 95 per cent, it would reduce the total bucket capacity to 16.15m3. To overload the machine, a material density of 2.13t/m3 would be required. But the client indicated that material of this density was unlikely at the project.

EX2600 Digger Fast Facts

Results
With the current fleet, re-fitting the original 17m3 bucket to the machine posed no significant risk to the asset, unless loose density of material regularly exceeded 2.1t/m3 with a fill factor of 95 per cent. Prior to fitting the bucket, a loose density study was conducted to confirm fresh rock above 2.1t/m3 was unlikely to occur.

With a spare 17m3 bucket on site, the switch was calculated to cost the client only $6,000. Our team’s in-depth cost modelling revealed the $6,000 spend would also result in a potential annual cost reduction of $220,000, or $500,000 in flow-on benefits.

The optimised scenario was subsequently executed on site, increasing the bucket capacity by 2m3 (from 15m3 to 17m3) by removing the reducing plates and re-fitting the original.

Summary
To continually achieve rising targets and improve efficiencies, it is important for mine sites to avoid complacency and seek new ways of doing things. We are committed to supporting our clients by presenting innovative solutions, identifying operational inefficiencies and recommending equipment modifications that will maximise production and profitability. In this case, the EOS team highlighted a low-risk strategy that improved the performance and efficiency of one of the site’s most important pieces of equipment as well as resulting in significant potential savings.