A Station Built on Precision
At Eskom’s Lethabo Power Station, Babcock is executing one of the most technically demanding maintenance programmes on the national grid – the overhaul of Pulverised Fuel (PF) Burners, PF piping systems and the station’s horizontal tube mills.
The work forms part of Eskom’s long-term reliability improvement plan aimed at stabilising generation and extending the life of critical plant assets. Awarded under the NEC3 Engineering and Construction Contract, the project draws on Babcock’s proven OEM expertise and its track record in delivering high-risk, high-precision boiler and milling maintenance.
First awarded in 2019 and renewed in 2022 for burners and again in 2024 for mills, the multi-year framework covers both planned outages and ad hoc maintenance interventions. Each task order includes inspection, dismantling, repair or replacement of critical components, reassembly, commissioning and performance testing – all to restore combustion efficiency and return units to service safely and on schedule.
Behind these milestones are the figures that matter: 1 537 project days completed, more than 2.55 million lost-time-injury-free manhours and an unbroken safety record. Success at Lethabo isn’t measured in reports; it’s measured in units that start up on time and stay online.
Inside the Overhaul
Each of Lethabo’s horizontal tube mills weighs roughly 300 tonnes and processes thousands of tonnes of coal daily. When a mill comes offline for refurbishment, every step – isolation, dismantling, inspection, repair, reassembly, alignment and testing – must run precisely to plan.
PF Burners are stripped and rebuilt, with worn tips, swirlers and registers replaced as needed. PF piping sections are renewed and aligned to specification. Inside the mills, liners, wear plates, bearings, oil systems and drive assemblies are overhauled before reassembly and balancing. Even a few millimetres of misalignment can create vibration and wear within hours of restart.
Material logistics are planned months ahead and interface meetings with Eskom’s outage management team ensure that all disciplines – mechanical, electrical, rigging and QA – stay aligned. Laser alignment tools and standard refurbishment jigs have reduced rework and shortened turnaround times. Each overhaul brings measurable gains: restored throughput, improved combustion efficiency and lower forced-outage risk. Every mill recommissioned adds megawatts back to the grid and confidence back to the system.
Engineering in Tight Spaces
Lethabo’s working conditions are complex: confined areas, ageing infrastructure and simultaneous operations across multiple disciplines. Every task is governed by Babcock’s Integrated Management System, certified to ISO 45001 for Safety, ISO 9001 for Quality and ISO 14001 for Environment.
Before any job begins, teams complete risk assessments and permit-to-work clearances. Daily safety briefings, confined-space controls and hot-work supervision are standard practice. Quality assurance runs alongside: dimensional checks, weld inspections and non-destructive testing with client hold points at critical stages.
Digital QA documentation now tracks progress in real time, giving engineers visibility from dismantling through final sign-off. Combined with precision laser alignment, these innovations have improved traceability, reduced vibration-related maintenance and tightened outage control. The result is a site where safety and quality are not competing priorities – they’re two sides of the same discipline.
The People Who Power the Process
At full execution, between 200 and 250 people work on the Lethabo contract – project managers, artisans, riggers, welders, inspectors, planners and learners. Daily coordination meetings align mechanical, quality, safety and logistics teams before any tools are lifted.
The workforce includes permanent Babcock employees and local recruits from the Vaal region. Apprentices and learners work under supervision of qualified artisans, gaining practical experience in mill and burner refurbishment. Mentorship is built into the process, ensuring skills transfer while maintaining safety and performance standards.
The results are visible: multiple mill and burner packages completed within outage windows, first-time-right quality acceptance and zero lost-time injuries. The record – more than 2.55 million safe manhours – reflects methodical planning and personal accountability. Many apprentices who began here have since qualified as artisans, proving that reliability isn’t only built into machinery; it’s developed in people.
Powering the Grid, Strengthening Capability
Every completed overhaul contributes directly to Eskom’s generation stability. Measurable improvements include increased mill throughput, consistent pulverised-fuel fineness, fewer forced outages and longer component life. Combustion efficiency has improved, reducing fuel use and stabilising boiler performance.
The benefits extend beyond technical gains. Local employment, supplier participation and training programmes in the Vaal region add socio-economic value to the engineering effort. The project exemplifies Babcock’s purpose of creating a safe and secure world together – delivering reliability to the grid while developing capability in the community.
Lessons That Last
Lethabo has refined how Babcock plans and executes complex maintenance across its energy portfolio. Early integration between engineering, safety and logistics has improved mobilisation. Standardised refurbishment and QA procedures have reduced variability and rework. Continuous coordination with Eskom’s maintenance and engineering teams has built shared accountability for performance.
Across 1 537 project days, the team has demonstrated that reliability is engineered, not promised. It is achieved through disciplined process, skilled people and the will to do things properly every single time.
At Lethabo, precision isn’t a tagline – it’s the measure of how South Africa keeps the lights on.
