Abstract: Under the national "double carbon" strategy, XLPE insulated cable is difficult to meet the needs of green and sustainable development, and the development of alternative thermoplastic insulation materials has become an important direction, among which polypropylene cable material has become a hot research direction. In the process of polypropylene cable production, the stress white ring occurs repeatedly in the insulation layer, which leads to the reduction of the mechanical strength of the insulation layer and affects the overall performance and life of the cable. In this paper, the white ring phenomenon in polypropylene cable production is simulated by designing a mold, and the reason of the white ring in stress is explained, and the problem is solved successfully by regulating the cooling process, which provides a strong technical guarantee for the green and efficient production of polypropylene cable.