Steel purlin is usually made of cold-formed steel that is thin enough to put screws through. Cold-formed steel is made by rolling or pressing thin sheets of steel into the desired shape. Usually in "C" shape or "Z" shape. Purlins are most commonly used in Metal Building Systems, where Z-shapes are utilized in a manner that allows flexural continuit1
A sandwich panel is one structure made of three layers of material: low density core inserted material in between two relatively thin steel skin layers.
China Manufacturer Wholesale Price Steel Structure Frame Zinc Coated Steel Profile C Z Galvanized C Z Purlins for Roof Support High Quality Warehouse Style House Plans Steel Structure Truss Purlin Hot Rolled Black Galvanized Channel Steel C Z Purlin