钢管的壁厚是多少啊？
在加拿大 1.B.I. Pipe sch.40 welded size: 28'' dia 6m length 2.1 unit- B.I. Pipe sch. 20 welde size: 26''dia 6m length 3. 1 unit- Carbon Steel Pipe sch.40 welded size: 28'' dia 6m length 4. 1 unit- Carbon Steel Pipe sch. 20 welde size: 26''dia 6m leng...华人论坛