Wire drawing machines
Rotating machinery and Milliken conductors: the new demands of HV and EHV cable manufacturing
Rising electricity demand, the rapid integration of renewable energy sources, and the expansion of cross-border transmission networks are driving significant investment in high-voltage (HV) and extra-high-voltage (EHV) power infrastructure. As a result, cable manufacturers are under increasing pressure to produce conductors capable of transmitting more power while meeting ever-higher standards of efficiency and reliability.
For manufacturers, expanding production capacity is only part of the challenge. Equally important is maintaining precise control over increasingly sophisticated manufacturing processes, where conductor quality has a direct influence on the electrical and mechanical performance of the finished cable.
The shift toward Milliken conductors
The evolution of HV and EHV cables is about much more than higher operating voltages. As conductor cross-sections continue to increase, current distribution becomes more difficult to manage, introducing challenges that cannot be addressed with conventional conductor designs.
To overcome these limitations, Milliken conductors are becoming the preferred solution for high-capacity power cables. Their segmented design improves current distribution, but it also places far greater demands on the manufacturing process. Throughout production, each conductive segment must maintain its precise position and orientation to ensure the conductor retains its intended geometry and delivers consistent electrical performance.
Why the drum twister matters
Producing Milliken conductors requires much more than simply twisting together multiple conductor segments. Every stage of the stranding process must be carefully controlled to preserve conductor geometry while ensuring stable material handling throughout the production cycle.
Developed by CORTINOVIS, part of TCS Machinery & Services since 2017, the drum twister is specifically engineered for the production of copper and aluminum Milliken conductors with cross-sections of up to 3,000 mm² and configurations of up to seven segments. The machine is designed to process large conductor assemblies while maintaining precise control of tension, segment orientation, and conductor geometry from start to finish.
Beyond mechanical strength: complete process control
CORTINOVIS drum twister lines are designed to handle reels up to 5,000 mm in diameter and total rotating masses of up to 60 metric tons, including both reel and product. Under these conditions, structural rigidity alone is not enough to guarantee production quality.
Consistent process performance depends on the seamless integration of payoffs, stranding and compacting units, capstans, taping systems, and take-up equipment, all coordinated through vector drives, encoders, and PLC-based control systems. Continuous synchronization of the entire production line maintains the correct relationship between linear speed, rotational speed, and conductor behavior, even during acceleration, deceleration, and machine stops.
For Milliken conductor applications, the line also incorporates dedicated systems to monitor and control the orientation of the individual conductor segments, together with specially designed guiding devices that preserve the final conductor geometry throughout the manufacturing process.
Engineering expertise for next-generation cable production
Designing production lines for HV and EHV conductors requires expertise that combines rotating machinery, automation, and advanced process control. With more than a century of experience in machinery for the wire and cable industry, CORTINOVIS applies this engineering heritage to the development of drum twister lines for high-capacity conductor production.
As conductor sizes continue to increase and cable designs become more complex, manufacturers are placing greater emphasis on production technologies capable of combining robust mechanical engineering with sophisticated automation and a deep understanding of conductor behavior. Integrating these disciplines has become a key factor in meeting the evolving requirements of the global power cable industry.
Bringing together the historic Cortinovis, Sictra, and Trafco brands, TCS Machinery & Services designs and manufactures complete production systems for power cables, telecommunications cables, and steel wire ropes. The company also supports manufacturers with revamping projects, technology upgrades, and original spare parts, helping improve the productivity and efficiency of existing production lines.
