WCA March 2016

Technology news

Technology news

FOR the production of high-voltage cables, quality is an essential factor. Failures of the cable, for example, can not only cause loss of reputation but also extremely high costs for the manufacturer. High-voltage cables are now equipped with cross-linkable polyethylene insulation, XLPE*. The manufacturing of the cable and the cross-linking of the insulation are part of a continuous process in CCV** or VCV*** lines. In order to generate the optimal cross-linking of PE insulation molecules, the XLPE material has to be heated in the CV-lines to a defined temperature. The extruded cable passes through a closed pressurised tube until all three layers of the insulation are completely heated and cross-linked. Non-contact temperature measurement in high-voltage cable production To speed up this process and increase the efficiency of production, it is recommended to heat up the wire from approximately 100°C to 120°C prior to entering the crosshead. Due to this method, the insulation is not only heated from the outside but also from the inside. Therefore, a faster cross-linking of the plastic material is achieved. In this context, the Sikora temperature measuring device Wire-Temp 6050, for product diameters from 5mm to 50mm, offers reliable temperature measuring values. By using the measuring data, which is taken by the device directly after the conductor preheating, the operator is able to precisely adjust the heating of the conductor according to the calculated needs. Therefore, the Wire-Temp technology ensures an optimal process efficiency, which is distinguished by continuity and repeatability of the process. *XLPE: Cross-linked polyethylene, **CCV: Catenary continuous vulcanisation, ***VCV: Vertical continuous vulcanisation Sikora AG – Germany Website : www.sikora.net ❍ The Wire-Temp 6050 is designed for conductor diameter up to 50mm

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Wire & Cable ASIA – March/April 2016