CASE STUDY - FIVES MAINTENANCE
how a production site transformed its maintenance department in eighteen months.
At its Gennevilliers site, Mersen entrusted Fives Maintenance with assessing the maturity of its maintenance department, then supporting a two-year transformation roadmap launched as a new maintenance manager took up his role.
Client
Mersen designs and deploys technologies at the heart of today's major energy and industrial transitions. Gennevilliers site, Hauts-de-Seine, France
Sector
Advanced materials: carbon, graphite and composite solutions for industry
Scope of work
Maintenance maturity assessment, RACI, equipment criticality analysis, CMMS configuration and spare parts management
Assignment duration
Assessment in December 2024, a two-year roadmap and eighteen months of support to date
About MERSEN
Mersen designs and manufactures carbon, graphite and composite solutions for some of the market’s most demanding industries. At its Gennevilliers site, the Group produces components for high-tech industries, with a maintenance department responsible for ensuring production equipment availability.
In late 2024, the site director reached a stark conclusion: the department was operating from day to day, with little formal structure. The production manager met Fives Maintenance at an industry forum, and site management commissioned a maintenance maturity assessment.
Challenge
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Two weaknesses were holding the department back
1/ A CMMS was in place but barely used: an assessment conducted by the software provider in January 2024 put its utilisation rate at 10%. Maintenance work was not consistently recorded, roles remained unclear, workloads were insufficiently planned, and maintenance expenditure was only reviewed after the fact.
2/ Spare parts were scattered across the site and managed outside the CMMS, with no parts register or stock tracking. The system’s dedicated module remained unused.
Site management made a deliberate timing decision: to align the assessment with the arrival of the new Maintenance Manager, Gobinath Sivapalan. This provided a shared diagnosis from the moment he took up his role, rather than leaving him to build a picture of the situation alone.
Solution
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Our approach
Fives Maintenance divided its support into short workstreams, each with defined deliverables, carried out on site alongside Mersen’s teams.
1. Assess maintenance maturity across six dimensions
In December 2024, the maintenance maturity assessment reviewed the department using Fives Maintenance’s methodology: technical practices, engineering, performance, organisation, people and quality. It confirmed observations from the shop floor, but above all replaced perceptions with facts. The assessment led to a two-year transformation roadmap, with priorities defined for each dimension.
2. Clarify roles and prioritise equipment
Between June and July 2025, two workstreams laid the foundations. A RACI matrix defined everyone’s responsibilities, from technicians to team leaders. Equipment criticality analysis focused maintenance efforts on the machines with the greatest impact on production. These deliverables were developed jointly with the teams, combining maintenance standards with the site’s own working culture. In November 2025, Mersen’s operational teams visited an aerospace customer site supported by Fives Maintenance, to compare their new ways of working with the practices of an already mature organisation.
3. Put the CMMS and spare parts management at the centre
In early 2026, Fives Maintenance supported CMMS configuration and the introduction of spare parts management, which had previously been absent from the system. Parts were brought together in a single storeroom. By May 2026, approximately 1,700 part references had been created in the CMMS, supported by team training and documentation. The final step, recommended by the assessment, was to create a Maintenance Methods Manager position—a role that had not previously existed within the site’s organisation. The person appointed, in post since 1 July 2026, oversees inventory management and CMMS administration.
The methodology no longer depends on the presence of an external service provider: it is embedded in the site’s organisation.
Results
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Testimonial
«Working with Fives Maintenance has enabled us to create processes and deliverables that make decision-making and the allocation of responsibilities easier. Everyone now knows what falls within their role.»
Gobinath Sivapalan
Maintenance Manager, Mersen, Gennevilliers site
600 → 60
maintenance requests outstanding for more than three months, against a target of fewer than 100
200+ → 10
maintenance requests awaiting approval in the CMMS, now processed on an ongoing basis (daily average)
1,700
spare part references created in the CMMS, compared with none initially
2 years
of transformation roadmap, prioritised across six dimensions and structured around quick wins
Beyond the figures, Mersen has changed the way it manages maintenance. The workflows and flowcharts developed jointly with Fives Maintenance are displayed on the shop floor: everyone understands their responsibilities, while management has a clear framework for making decisions and recognising progress. The transformation is continuing: the spare parts workstream is estimated to be 70% complete and is now led by the site’s Maintenance Methods team.
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