避雷针采用不锈钢钢管制作时,其管壁厚度应不小于( )。A.1.5mm B.2mm C.2.5mm D.3mm

作者: rantiku 人气: - 评论: 0
问题 避雷针采用不锈钢钢管制作时,其管壁厚度应不小于( )。
选项 A.1.5mm B.2mm C.2.5mm D.3mm
答案 D
解析 避雷针材料要求。一般用镀锌(或不锈钢)圆钢和管壁厚度不小于3mm镀锌钢管(或不锈钢管)制成,热镀锌镀层的厚度应不小于65μm。屋面上常用的是5m及以下避雷针。在有热镀锌条件时,5m及以下的避雷针应在制作后整体热镀锌。

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