December 10, 2014

Sounds like a good news for rubber cable manufacturers. Would you like to significantly cut costs in your medium voltage rubber cable production? With Continuous Type Change (CTC) it is possible. The principle idea of CTC is to change tooling for the next product without stopping the line.

It is well known that type changes take time when they are done in the conventional way. By installing CTC into your crosshead, enables type changes in a blink of an eye. Not only a great deal of valuable time is saved but also material and energy. Conventional type changes always require hours of down time and piles of scrap material, but type changes with CTC require only minutes and nearly nonexistent cable loss.

CTC is already widely used in XLPE medium voltage cable production around the world by several cable makers. To serve an even broader clientele Maillefer is now developing CTC for rubber insulated medium voltage cables. And the first steps have been truly successful. A series of test runs have been made, including three changeovers with a 20 kV cable. The test series was initiated with a conductor cross-section area of 240 mm2 and concluded with a 50 mm2 conductor. The cables were cured in nitrogen atmosphere.

A good example of the CTC benefits is a medium voltage cable calculation. Based on an average of recent insulation material price levels, type change costs without CTC can be up to EUR 5 000 per change and with CTC are only EUR 75. Thus for example, the monthly costs with three type changes per week without CTC can go up to EUR 60 000 compared to the very moderate costs of only EUR 900 with CTC. And do not forget profits gained from the production time savings which can amount to an even greater value.

CTC can seriously reduce the overall downtime when frequent type changes need to be done in cable production. The other good news is that CTC does not require heavy investments and is nevertheless a very effective tool for improved productivity.