... building /warehouse construction Qingdao Baoduo Steel Structure CO.,LTD.Main Grade: Q345B,Q235B Standard:ISO9001,BV CertificationAAA Credit ... ,Logistic centers,and all kinds of steel materials.,etc.Specifications:Main Steel: Q345B,Q235BColumn&Beam: Welded or Hot rolled ... to contact us for anything you needed.Detailed specifications:1. The main frame (columns and beams) is made of welded ...