发布时间:2025-01-30 23:15:04
正方形和长方形(矩形)截面碳钢:每米重量单位:kg/m(千克/米)&lb/ft(磅/英尺)公式:kg/m=(Oc-4Wt)*Wt*0.00785其中:Oc是外周长,Wt是壁厚;正方形Oc=4*a长方形Oc=2a+2ba,b是边长
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