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A 285 / A
285M -
90 |
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PRESSURE VESSEL PLATES, CARBON
STEEL, LOW AND INTERMEDIATE TENSILE STRENGTH |
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1 Scope |
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1.1 This specification covers carbon steel plates of low -
and intermediate-tensile strengths which may be made by
killed, semi-killed, capped, or rimmed steel practices at the
producer’s option. These plates
are intended for fusion-welded pressure vessels. |
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1.2
Plates under this specification are available in three grades
having different strength levels as follows: |
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Grade |
Tensile strength ksi[MPa] |
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A |
45-65 [310-450] |
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B |
50-70 [345-485] |
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C |
55-75 [380-515] |
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1.3 The
maximum thickness of plates under this specification, for
reasons of internal soundness, is limited to a maximum
thickness of 2 in. [50 mm.] for all grades. |
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1.4 The
values stated in either inch-pound units or SI units are to be
regarded separately as standard. Within the text, the SI units
are shown in brackets. The values stated in each system are
not exact equivalent; therefore, each system must be used
independently of the other. Combining values from the two
systems may result in nonconformance with the specification. |
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2
General Requirements and
Ordering Information |
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2.1
Material
supplied to this material specification shall conform to
Specification A 20/A 20M. These requirements outline the
testing and retesting methods, and procedures, permissible
variations in dimensions and mass, quality and repair of
defects, marking, loading, etc. |
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2.2
Specification A 20/A 20M also establishes the rules for the
ordering information that should be complied with when
purchasing material to this specification. |
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2.3 In
addition to the basic requirements of this specification,
certain supplementary requirements are available when
additional control testing or examination is required to meet
end use requirements. The purchaser is referred to the listed
supplementary requirements in this specification and to the
detailed requirements in Specification A 20/A 20M. |
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2.4 If
the requirements of this specification are in conflict with
the requirements of specification A 20/A 20M, the requirements
of this specification shall prevail. |
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3 Heat
Treatment |
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3.1 Plates are normally supplied in the
as-rolled condition. The plates may be ordered normalized or
stress relieved, or both. |
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4 Chemical Requirements |
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5.1 The steel shall conform to the requirements
shown in Table 1. |
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5 Mechanical Requirements |
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5.1 Tension Tests: |
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5.1.1 Requirements - The material
as represented by the tension-test specimens shall conform to
the requirements shown in
Table 2. |
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Table 1 :
Chemicals Requirements |
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Elements |
Composition % |
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Grade A |
Grade B |
Grade C |
| Carbon, max |
0.17 |
0.22 |
0.28 |
Manganese, max
Heat analysis
Product analysis |
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0.90 |
0.90 |
0.90 |
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0.98 |
0.98 |
0.98 |
| Phosphorus,
max |
0.035 |
0.035 |
0.035 |
| Sulphur, max |
0.035 |
0.035 |
0.035 |
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Table 2 :
Tensile Requirements |
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Grade A |
Grade B |
Grade C |
| |
ksl |
[MPa] |
ksl |
[MPa] |
ksl |
[MPa] |
| Tensile Strength |
45-65 |
[310-450] |
50-70 |
[345-485] |
55-75 |
[380-515] |
| Yield strength, min |
24 |
[165] |
27 |
[185] |
30 |
[205] |
| Elongation in 8 in. or
[200 mm], min, % |
27 |
25 |
23 |
| Elongation in 2 in. or
[50 mm], min, % |
30 |
28 |
27 |
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Governing Specifications |
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