... elegant 3) practical and economy 4) easy to construct portal frame steel structureSteel Structure Warehouse/ Workshop1. Item Name: steel structure ... C. We have pretty good preservative treatment on this steel frame as follows,a. Clean the steel( reach to Sa2. ... for example, steel bracket, bolts, self-drilling screw, rivet, inter and outer cullis, rainspout, trimming sheet, glass cement, etc. you ...