3mm的不锈钢天沟需要两面焊接吗?... 西安华久钢铁物资有限公司

p1Src=//y3.yzimgs.com/uploads_old/373932/2014082209170457_old.jpg&p2Src=//y3.yzimgs.com/uploads_old/373932/2014082209170457_old_1.jpg&p3Src=//y3.yzimgs.com/uploads_old/373932/2014082209170457_old_2.jpg"