POWER CABLE INSULATION PRODUCTION LINE CONTROL

Abstract

The paper considers the problem of control the cable insulation continuous vulcanization line. The axisymmetric mathematical model of the power cable rubber insulation vulcanization technological process has been developed. The model describes the heat transfer process inside the vulcanization pipe and the vulcanization process kinetics inside the insulation. The mathematical model is based on the energy conservation equation and it is presented in the form of a differential equations system closed by boundary conditions The mathematical model makes it possible to estimate the influence of various technological and design parameters on the temperature distribution along the radius and length of the cable. Based on the temperature distribution curves, the cable insulation vulcanization degree is calculated The study of the raw rubber compositions vulcanization properties was carried out by rotary rheometer, where the samples of the material were subjected to an oscillating load at different temperatures. As a result of the experiment, the curves family of the torque dependence on the curing time at different temperatures was obtained. To describe the vulcanization process kinetics, a parametric expression is used based on the experimentally obtained torque dependences. The obtained temperature dependence of the parametric expression coefficients makes it possible to describe the vulcanization process taking into account the uneven temperature distribution along the cable radius and length. The developed model makes it possible to calculate the speed at which the vulcanization degree reaches a given value. Algorithms for calculating and correcting line speed and extruder flow rate are proposed on the basis of a mathematical model. It allows us to determine the speed and flow rate of the extruder for various: cable designs, insulation materials, abnormal operating conditions of the production line. The results can be used at enterprises engaged in the production of cable and wire products with cross linked insulation. In cases where it is required to quickly calculate a new technological mode, make changes to the cable design, change the insulation material, and also take into account possible pressure drops inside the vulcanization pipe and deviations in the cable properties during the production process.