Drives, motors + switchgear
Looking ahead TheVyeboomprojectdemonstratedthatlastingprogressininfrastructure depends on collaboration as much as on hardware. It’s about building the confidence to change what already works, to make it work better, and that confidence comes from collaboration. Boards, consultants, suppliers, and engineers each brought their own perspective, and connecting those perspectives turned risk into momentum. For farmers, the outcome was reliable water when it was needed. For the irrigation board, it was confirmation that modernisation can be approached with confidence. And for the partners involved, it was evidence that independent expertise, when combined, can deliver outcomes greater than the sum of the parts. For the Vyeboom Irrigation Board, this modernisation has become a reference point. Acknowledgements to ElectroMechanica for permission to republish this article in Electricity + Control . For more information visit: www.em.co.za
performed under real conditions. The visit helped strengthen confidence in the decision to proceed with the upgrade. By the time the drives were commissioned for the Vyeboom pump station, the project was no longer seen as a risk but as a proven, long-term solution. As well as delivering new hardware, the project reinforced confidence in modernisation, built step by step through independent expertise, shared accountability, and operational proof. The outcome When the new drives finally started the pumps, the first dierence was obvious. Starts and stops were smooth, water hammer was gone, and farmers could count on water without interruption. But the bigger change unfolded in some unexpected ways. At Vyeboom, the board gained renewed confidence in modernisation. Seeing the system work in practice gave them the confidence to plan similar upgrades across their other stations – decisions that, only months earlier, had seemed out of reach.
Drives, motors + switchgear : Products + services
Refurbishing a 15 MW wound rotor induction motor
This challenging 15 MW stator and rotor rewind project for a platinum mine represents a significant achievement in motor refurbishment and demonstrates Marthinusen & Coutts’ capabilities in adhering to industry standards and ensuring meticulous attention to detail. The project was awarded to Marthinusen & Coutts (M&C), a division of ACTOM, in late November 2024. It involved a comprehensive overhaul of a motor that had been in service for over 18 years and the contract was awarded to M&C due to the company’s proven, successful repairs and its intricate knowledge of the design of these 15 MW motors. The primary objective of the rewind project was to restore the motor to its original high standards – as when it was initially manufactured. This goal required a thorough scope of work, including: - Rewinding the stator and rotor, incorporating steel binders into the rotor windings – a complex and diicult task to execute - Overhauling the brush gear compartment and installing new brushes - Re-insulating the slip rings with new insulation material - Installing new heat exchangers - Conducting sha¡ repairs and fully refurbishing the white metal bearing assemblies - Dynamically balancing the rotor - Skimming the stator feet and pedestal bearings - The complete assembly of the motor - Finally, a no-load test run was performed, and the motor was repainted to complete its restoration. Technical challenges and solutions The rewind process proved challenging, especially concerning the use of steel binders on the rotor. M&C engaged an expert cra¡sman with 35 years of experience in fitting these complex components. The project’s complexity required precautionary
measures during critical stages, including the burnout, coil manufacturing, VPI (Vacuum Pressure Impregnation), and curing cycles, as well as balancing to ensure the rotor met a tolerance of G 0.4. In selecting materials for the rewind, M&C, in consultation with its international insulation experts, chose a comprehensive insulation solution. Project management and compliance To keep the project on schedule, M&C adopted a proactive approach, although some delays occurred due to the complexities of the VPI processes. The project management methodology included clearly defined hold points, as requested by the customer. M&C’s Quality Control department communicated regularly with the customer, providing updates when hold points were ready for inspection. Safety was a top priority throughout the rewind process. Marthinusen & Coutts restored the 15 MW motor to its original high standards.
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MAY 2026 Electricity + Control
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