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Back to basics at Richards Bay Minerals’ mining operation
Mission-Directed Work Teams (MDWT) started at RBM in 2005 in order to establish business focus, goal alignment and visual management of safety, quality, speed and cost performance throughout the organisation.
Improvement Project
The following Six Sigma project example represented significant value creation, with details being omitted due to the sensitivity of the data.
This example comprises the tailings disposal system (tails) of Mining Pond Echo (MPE) that, prior to 2006, was causing a significant throughput bottleneck. Unscheduled tails production downtime was identified as the focus (leverage point) area as it contributed to the largest portion (47% in 2005) of tails downtime. Pareto analysis revealed that tails stacker moves and polypipe/hose failures were the largest causes of production downtime.
To achieve a reduction in tails downtimes, data quality on the tails system was firstly addressed by improving downtime coding and correcting system calculation errors. Data resolution was also improved by introducing polypipe/hose repair recording sheets, which revealed that bolting and slip rings (gaskets) were the largest contributors to downtime. There was thus a need to get BTB to ensure that the fundamentals of a slurry operation were adhered to.
Work instructions were then created (at operator level) to reduced both polypipe/hose failures and the time to move stackers. Stackers were also moved on-the-run when it was safe to do so and were set-up correctly during day shift so that only minor moves were required during night shift. Large improvements were also made through operator awareness by training them on the impact of equipment damage to production throughput. In other words, developing understanding on the impact of doing the tasks poorly. This was driven through teamwork initiatives and included within the relevant training modules.
The combined result was a reduction of unscheduled production downtime by 50% and total tails downtime of 30%. Production throughput was simultaneously addressed by running MPE as a four tails operation when there was capacity to do so, as the perceived risk of negatively affecting the water balance was invalid. These combined improvements have seen an increase in throughput at MPE of 4.5% and have been sustained for over a year.
Conclusion
Mission-Directed Work Teams remains the single most important factor in ensuring and sustaining Six Sigma project gains and is currently the catalyst to change to a data focused culture. Mission Directed Work teams are also fundamental in driving leadership goals and expectations to the teams.
References
Excerpts from article: WARE, C.I. Back to Basics at Richards Bay Minerals’ mining operation: examples using Six Sigma methodology. The 6th International Heavy Minerals Conference ‘Back to Basics’. The Southern African Institute of Mining and Metallurgy, 2007.
Retaining the ‘basics’ are of paramount importance in ensuring an efficient mining operation.
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