... -bending performance 3.Good straightness 4.Reliable performance C/Z type channel steel purlins features : Standard:AISI, ASTM, BS, DIN, ... GB, JISGrade:Q215,Q235,A36,SS400,SS540Commoditystructural steel C/Z type ... wall beam of steel structure buildingC/Z type channel steel purlins advantage:(1). Design according to customers’ requirements(2). ...