EuroWire January 2025

Technology News

Quality control along the entire CV line HV and EHV cables place high demands on their function and their production. As submarine and underground cables, they ensure that electricity is reliably transported to where it is needed.

The Purity Scanner Advanced inspects 100 per cent of the material for purity before extrusion and automatically removes contaminated pellets, such as those with metallic impurities from 50μm. This ensures that only high-quality, pure material enters the extruder. Another important factor is the melt temperature of the XLPE material during extrusion. The right temperature ensures a homogeneous polymer melt and prevents premature cross linking. The Ultratemp 6000 is used in the flow channel between the extruder and crosshead to continuously measure the melt temperature, enabling optimum extruder output. The optimised output also allows an increase in the length that can be produced before needing to stop the CV line to clean the extruder, screens and extrusion tools. This not only leads to higher efficiency, but also reduces the number of cable joints. Directly after the crosshead, another Sikora system is used: the X-Ray 8000 Advanced measuring system precisely records the dimensions of the cable, including wall thickness, eccentricity, diameter and ovality, directly in the CV tube. Visualised in real time, the measured values enable quick centring of the extrusion tools and distortion-free control to the nominal dimension. At the end of the CV line, the X-Ray 8700 NXT measuring system ensures precise measurement of the “cold values” of the cable. In combination with the X-Ray 8000 Advanced at the beginning of the line, the shrinkage values for all three insulation layers of the cable can be precisely determined. The operator is shown whether the eccentricities of the individual layers and the ovality between the hot and cold measuring points have changed, which is important information during the cross linking process in the CV tube. Finally, the LM Smart length measurement system at the end of the CV line ensures that the required cable length is precisely maintained. Sikora AG www.sikora.net

A recent report identifies cable failures as one of the greatest challenges for offshore wind power in the future, and predicts around 3,600 cable failures between 2024 and 2035, which could potentially lead to costs of more than €60bn. The quality of these cable types should be ensured at the highest level. The latest inspection and measuring technologies from Sikora monitor the plastic material for the insulation as well as the cable dimensions at crucial positions in CV lines. The purer the XLPE material used, the lower the risk of cable breakdown and the higher the life expectancy of the cable. In particular, when manufacturing long cable lengths, manufacturers aim at using as few cable connectors (joints) as possible, which is why material purity is critical. In addition to using melt screens after the extruder, the testing and sorting of pellets before extrusion is of central importance.

The integration of Sikora inspection and measuring systems along the entire CV line to ensure continuous quality of HV and EHV cables

Stakes too high to ignore obsolescence?

OEE availability; saving on capital expenditure while benefiting from new technologies; guaranteed spare parts availability; increased reliability and machine lifetime; and reduced maintenance costs. Spare parts are readily available for the upgraded machinery, and operators and maintenance personnel will already be familiar with the equipment. Using a clearly defined procedure, Maillefer can prepare the migration pro ject for minimal risks. Having a reliable fall-back strategy offers protection once the systems are up and running. Maillefer Extrusion Oy www.maillefer.net

package offers equivalent features. The originally programmed sequences are translated and accurately compiled into the newer technology. The selected motors/drives are ensured to be fit for the task. Built on ABB’s all-compatible drives architecture, operators are given high levels of compatibility, flexibility and ease of use. Upgrading the drives with new technology is not only preventive maintenance but also a sustainable action. The claimed benefits of upgrading include guaranteed support of equipment and specialised personnel; the most modern technologies available; reduced risk of breakdown and improved

Extrusion manufacturer Maillefer is highlighting the risks of obsolete motors/drives. The company recommends upgrading, in order to avoid the increasing difficulty of sourcing identical parts for older machines. Compatible replacements and equivalent programming carry their own risks. Maillefer offers a motor/drive upgrade package that extends the lifetime of the extruder’s robust construction, with the reassurance of an essential component that will continue to perform as before. Planning to modernise an extruder ensures future processing capability. The models concerned are BMA, BMX, BMO, BMN, NMA, NMB, NMC, MXC and MEA. machinery

A Maillefer-sourced motor/drive upgrade

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January 2025