STRESS FIELD IN EXTRUDED CABLES DUE TO COOLING PROCESS

The cooling process used during the extrusion coating of cables causes a complex temperature distribution in the polymer layer. A stress field is formed due to temperature inhomogeneity in the polymer layer. A cooling and stress distribution model has been developed and investigated. The material parameters (heat conduction coefficient, specific heat, density and heat expansion coefficient) depend on the temperature, while the shear modulus depends on both the temperature and loading time. In the model a regression equation was used to describe material parameters. Air and water-cooling methods were investigated. The cooling rate has a significant effect on the radial stresses formed in the polymer layer during cooling.