Abstract
This paper summarizes the work done from November 2022 to August 2023 to improve reliability of a CIP Gold Mill. Availability was on a downward trend in 2022 and had fallen below 90% at the time of the intervention. This negatively impacted production to the extent that the company had to revise corporate guidance downward in the third quarter of 2022. Factors contributing to this trend included:
- high turnover rates within the Mill Maintenance Department and prolonged vacancies during the recruitment process
- the SAP build, done during plant commissioning, was generic and had never been updated using actual failure data nor for equipment added after commissioning,
- There was no formal reliability process with defined roles or targets.
A formal assessment of Mill Maintenance was completed in August 2022 and the outcomes included a recommended Improvement Roadmap and a Business Case built on incremental mill runtime. Implementation of the improvement Roadmap began in November 2022 and improved results began to appear as early as January 2023. Improvements were driven by the following parallel workstreams:
- Shutdown Execution improvement raised planned work order completion rates from about 65% to over 90%, and
- a Reliability Improvement program was implemented to identify and mitigate the Top 10 Reliability “bad actors”.
This paper focuses on the Reliability Improvement program.
It should be noted that two other enabling workstreams were carried out at the same time, those being Planning & Scheduling as well as Maintenance Management, the latter of which was designed to create and maintain alignment within the maintenance department as well as with other key departments.
By August 2023, these efforts reduced the number of unplanned downs by 43% compared with the failure rates experienced during 2021 and 2022. This was despite two significant unexpected setbacks including replacement of the primary crusher due to catastrophic failure and the sudden reduction in SAG mill liner life, which bottomed out at 2 months before recovering.
The paper describes all aspects of the reliability improvement process including:
- creating alignment on the goals and how the results were to be measured
- collecting, cleaning and converting data into actionable information
- driving mitigating action, and
- installing tools and defining behaviors to not only sustain the improvement, but to ensure continued improvement.
The paper discusses the results obtained over the nine-month engagement and key learnings.
Paul Batten