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4分管是16还是20
更新时间: 2020-12-29 00:00:00  

四分管外径为20毫米,管径应以mm为单位。 水煤气输送钢管(镀锌或非镀锌)、铸铁管等管材,管径宜以公称直径DN表示;无缝钢管、焊接钢管(直缝或螺旋缝)、铜管、不锈钢管等管材,管径宜以外径*壁厚表示;钢筋混凝土(或混凝土)管、陶土管、耐酸陶瓷管、缸瓦管等管材,管径宜以内径D表示;塑料管材,管径宜按产品标准的方法表示;当设计均用公称直径DN表示管径时,应有公称直径DN与相应产品规格对照表。

关键词: 分管 还是

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