咨询热线:010-6973-5438 标准号 中文名称 英文名称 DIN 47409-1985通信软线用折套管(Protective sleeves against kinking for telecommunication cords) DIN 4741-1-1984室内通风设备.聚丙烯管.最小壁厚的计算(Ventilation plants; polypropylene (PP) pipes; calculation of the minimum wall thickness) ...