Modelling and simulation of the continuous power cable processing

Abstract

The production of medium-voltage power cables consists of two main stages: (1) heating and crosslinking reaction and (2) cable cooling. The crosslinking reaction takes place in the heated part of the vulcanization tube. The cable cooling is divided in two parts. First, part of the tube filled with cold water is cooled under high pressure. Second, the cable is cooled in the air before the end of the process. In this article, part of the process prior the cooling will be discussed. A numerical model was constructed by taking into account the heat transferred by conduction through the cable, as well as kinetics of the heat generated by cure reaction in the insulation. The shared contributions of the convection and radiation heat transfer through the pressured nitrogen were included in the heat transfer coefficient. The model was applied to a real plant production process. The calculated degree of crosslinking shows that uniformity through the insulation along radial axis at the end of the heated part of the vulcanization tube is the main requirement for the application of the product. The conversion reaches 99% as a result of the implemented real process parameters (line speed, temperature in the tube, nitrogen pressure) in the model.