Optimum Curing and Full-out Velocity in the Rubber Extrusion Process for Electric Cable Manufacture

전선피복용 고무압출가공 공정의 최적 경화 및 선출 속도

In electric cable industries, the curing extent of the rubber materials covering the electric cores gives an significant effect on their final performance. The curing extent of rubber is controlled mostly by pull-out velocity of cable in the extrusion process. The final curing extent may be different for different radial positions inside the rubber because of the non-uniform temperature distributions during the curing process. In this contribution, the prediction of curing extent distribution throughout the radial direction of rubber is represented when the cable is passing through the steam curing zone with a fixed pull-out velocity. The prediction of the optimum pull-out velocity for the desired curing extent distribution is also reported. The steady-state heat balance was developed for the curing and cooling processes in which the pull-out rubber was cured by high temperature steam and then cooled by ambient water. A few essential material properties such as density, specific heat, and thermal conductivity were measured to analyze the temperature distribution during the curing and cooling processes. The times to reach 90% curing extent at varying temperatures were measured and used to determine the final cure extent distribution inside the rubber.