A537 CL1 steel plates is star production in BBN steel. ASTM A537 CL1 steel is a material with higher yield and tensile strength, used in the fabrication of pressure vessels and steel boilers. The steel contains the alloying of carbon, manganese and silicon and is heat treated using the quenched and tempered method which gives the material its residual strength. Sourced by the world;s leading fabricators, ASTM A537 CL1 is a material used extensively by the oil, gas and petrochemical industry.ASTM A537 CL1 is a kind of carbon-manganese-silicon heat treated steel plate, intended for welded pressure vessels and structures.A537 CL1 steel plates are engineered to be used in pressure vessel applications.