Structural Steel.

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Structural Steel.
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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.

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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.

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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.

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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.
  

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The New Specs.
BS 4360
SANS 1431
SANS50025 EN10025
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Grades
43A
300WA
50B
S275JR
350WA
S355JR
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Steel Yield Tensile Impact
43A 275 430/580
300WA 300 430/580
S275 275 430/580
350WA 350WC 350 350 490/640 490/640 27J _at_ 20
50C S355JR 350 350 490/640 490/640 27J _at_ 0 27L_at_ 20
Corten 350 480
Sup TM 190-500 Up to 560
RT 700 700 780/930 27J_at_ -50
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Specification Comparison
BS 4360 1986 EN 10025 1993 SANS 1431 SANS 50025 / EN 10025
Gr 40 A
S 235 JR 240WA S 235 JRAR
Gr 40 B S 235 JR G2
Gr 40 C S 235 JO 240WC S 235 JO
Gr 40 D S 235 J2 G3 240WDD S 235 J2N
Gr 43 A
Gr 43 B S 275 JR S 275 JRAR
Gr 43 C S 275 JO S 275 JO
Gr 43 D S 275 J2 G3 S 275 J2N
NONE NONE 300WA NONE
Gr 50 A
Gr 50 B S 355 JR 350WA S 355 JRAR
Gr 50 C S 355 JO 350WC S 355 JO
Gr 50 D S 355 J2 G3 350WDD S 355N
S 355 J2 G4 (AR or N)
Gr 50 DD S355 K2 G3 S355NL
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Impact Requirements

• JR 20degC (or none)
• JO 0 degC
• J2G3 -20 degC.
• N Normalised.
• E (Prefix) Engineering Grade.

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Strength of Steels
Domex.
S275
S355
S700MC
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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

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Pressure Vessel Grades

• SANS50028 EN10028 Replaces BS1501
• Grade 430A P265GH,
• Also P235GH, P265GH P295GH

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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.

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Advantages

• Mass reduction possible
• Possibility of replacing more expensive Quenched
  and Tempered plate (up to 10mm)
• Steel available with better resistance to
  mechanical damage.

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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.
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The New Product Range
Spec. Supraform 315MC/EN10149-2 S315MC Supraform 355MC/EN10149 -2 S355MC Supraform 420MC/EN10149-2 S420MC Supraform 550MC/EN10149-2 S550MC
Quality Code 556 000 557 000 550 000 530 000
Slab Widths 1300 9601300 16001870 9601300 1600 13001600
Thickness Range 2,0 - 6,0 2,0 10,0 2,5 10,0 3,0 8,0
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High Strength Steels.
RULE OF THUMB FOR MASS SAVINGSgt
t2
Re1
t1
Re2
t Thickness Re Yield Strength 1 Reference
Steel 2 High Strength Substitute.
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Dont over design!