Six Sigma in maintenance

Six Sigma is a data-driven process improvement methodology and uses DMAIC (Define-Measure-Analyze-Improve-Control) as a project management cycle.

It started by being applied in production processes and is currently used in all business sectors, including telecommunications, financial services, maintenance activities, logistics, human resources and public services.

Here is an example of the successful use of Six Sigma methodology to meet and even exceed Critical Customer Requirements (CCC)

• Despite annual maintenance costs (CAI) exceeding 150,000 euros, equipment/machine breakdowns, especially in the peak of the season, were increasing, leading to increased operating costs, loss of income and causing customer dissatisfaction.
• A Six Sigma Project was launched to identify the root causes of the poor maintenance process. The fixed objective was to reduce the total number of defects (NTD) by 5% and the total time to failure (TTOA) by 10%. The tools used included stakeholder analysis, Voice of the Customer (VoC), process mapping (CP), capability analysis, root cause analysis and hypothesis testing. The identified root causes were: wrong maintenance practices and problems with equipment wear (generating 76.4% of defects).

• The solution was defined during the Improvement phase and consisted in the introduction of Total Productive Maintenance (TPM) based on a better understanding of the problems related to wear. This better understanding was developed using a tool called Failure Modes and Effects Analysis (FMEA). NTD was reduced by 7% and TTOA decreased by 14%. The Plan-Execute-Verify-Act (PEVA) approach is now successfully applied to achieve operational excellence in maintenance activities.