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Structural Steel. Commercial Quality. For general engineering work that does not require specified mechanical properties. Test certificate is available, stating Chemical Analysis, no mechanicals. May be produced to SAE specs. May be welded and subjected to “Moderate” forming.
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Commercial Quality • For general engineering work that does not require specified mechanical properties. • Test certificate is available, stating Chemical Analysis, no mechanicals. • May be produced to SAE specs. • May be welded and subjected to “Moderate” forming. • What a customer usually wants when asking for “Mild Steel.
Commercial Quality • Should only be used where no specific mechanical requirements exist. • Not recommended for structures where any danger of “catastrophic failure” exists. • There is very little recourse to the mill in the event of failures.
Structural Steels. • Used where chemical and mechanical properties are required and specified. • Always supplied with test certificates. • Available in plate, sheet, sections, tube etc. • May be grouped in Low, Medium and High Strength structural steels.
Structural Steels • Used where structural properties are required. Engineers can design, using these properties. • With correct design and guaranteed structural steel, failures should be avoided. • Using steels of higher Yield and Toughness, allows thinner steel & hence, lighter structures.
The New Specs. BS 4360 SANS 1431 SANS50025 EN10025
Grades 43A 300WA 50B S275JR 350WA S355JR
Impact Requirements • JR = 20degC (or none) • JO = 0 degC • J2G3 = -20 degC. • N = Normalised. • E (Prefix) Engineering Grade.
Strength of Steels Domex. S275 S355 S700MC
WHAT IS COR-TEN® ? • Description • Cor-Ten® is a high strength low alloy weathering steel conforming to ASTM A242 Type 1. It derives improved corrosion resistance compared with carbon steel by the formation of a stable, adherent patina of corrosion product under suitable exposure conditions, inhibiting further corrosion attack. • Cor-Ten® is a registered trademark of USX Corporation
Pressure Vessel Grades • SANS50028 EN10028 Replaces BS1501 • Grade 430A = P265GH, • Also P235GH, P265GH & P295GH
High Strength, formable, sheet • There is a great deal of development around hot rolled thermo-mechanically rolled, inclusion shape controlled sheet, in thickness 2mm –12mm. • From hot strip mills, and particularly for the motor, materials handling and trailer industry. • Grades from 400 –700Mpa Yield Strength. • These steels give mass saving advantages and are very formable and weldable.
Advantages • Mass reduction possible • Possibility of replacing more expensive Quenched and Tempered plate (up to 10mm) • Steel available with better resistance to mechanical damage.
Supraform –Spec. Changes Supraform TM290 and TM340 to be replaced by S315MC Supraform TM380 to be replaced by S355MC Supraform TM460 to be discontinued. Supraform TM500 to be replaced by S460MC. Supraform TM600 to be replaced by S550MC S700MC already available ex import, Mittal to continue development.
High Strength Steels. RULE OF THUMB FOR MASS SAVINGS> t2 Re1 t1 Re2 t= Thickness Re= Yield Strength 1 = Reference Steel 2 = High Strength Substitute.