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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Specification Comparison
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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
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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!