... produce light and heavy steel structure buildings in protal frame and dome frame, such as warehouse, workshop, storage, hangar, chicken ... station, gas station etc.Main frame: welded H beam and column ,surface of steel with painted or galvanized ;Purlins: hot ... or electrical roller door etc.Accessories : down pipe (pvc ), gutter, ventilator, deck sheet, foundation bolts, normal bolts,bracket bolts, ...