A387 Grade 22 Class 2 is a grade of chromium-molybdenum alloy intended primarily for use in welded boilers and pressure vessels which are designed for use in raised temperature service. With excellent heat resistance and anti corrosive/oxidation qualities, this steel grade is ideal for use in the chemical, oil and gas industry.
Different Grades of ASTM / ASME Grade 22 Chromium-Molybdenum Alloy
Masteel's range of ASTM / ASME A387 Grade 22 chromium-molybdenum alloy products are available in different grades listed in the following.
- ASTM A387 Grade 22 Class 2
- ASME SA387 Grade 22 Class 2
Equivalent Grades of A387 Grade 22 Chromium-Molybdenum Alloy
The equivalent grades of A387 Grade 22 chromium-molybdenum alloy are as follows:
|
BS
|
EN
|
ASTEM/ASME
|
DIN
|
|
622-515B
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10 CRMO 910
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A387-22-2
|
10 CRMO 910
|
Chromium and Molybdenum Composition of A387 Grade 22 Chromium-Molybdenum Alloy
The chromium and molybdenum contents of A387 Grade 22 chromium-molybdenum alloy (according to the ASTM specification) are outlined in the following table.
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Designation
|
Nominal Chromium Content (%)
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Nominal Molybdenum Content (%)
|
|
A387 Grade 22
|
2.25%
|
1.00%
|
Tensile Requirements for A387 Grade 22 Chrome Molybdenum Class 2 Plates
The tensile requirements for A387 Grade 22 chromium-molybdenum alloy Class 2 Plates are listed in the following table.
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Designation
|
Requirement
|
Grade 22
|
|
A387 Grade 22
|
Tensile strength, ksi [MPA]
|
75 to 100 [515 to 690]
|
| |
Yield strength, min, ksi [MPa]/(0.2% offset)
|
45 [310]
|
| |
Elongation in 8 in. [200mm], min %
|
-
|
| |
Elongation in 2 in. [50mm], min, %
|
18
|
| |
Reduction of area, min %
|
45 (measured on round specimen)
40 (measured on flat specifmen)
|
Chemical Composition of A387 Grade 22 Chromium-Molybdenum Alloy
The chemical composition of A387 Grade 22 chromium-molybdenum alloy from heat and product analysis is summarised in the following table.
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Element
|
Analysis
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Chemical Composition (%) inc. Grade & UNS No.
|
| |
|
Grade 22 (UNS: K11757)
|
|
Carbon:
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Heat Analysis:
Product Analysis:
|
0.05 - 0.15
0.04 - 0.15
|
|
Manganese:
|
Heat Analysis:
Product Analysis:
|
0.30 - 0.60
0.25 - 0.66
|
|
Phosphorus:
|
Heat Analysis:
Product Analysis:
|
0.035
0.035
|
|
Sulphur (max):
|
Heat Analysis:
Product Analysis:
|
0.035
0.035
|
|
Silicon:
|
Heat Analysis:
Product Analysis:
|
0.50 max
0.50 max
|
|
Chromium:
|
Heat Analysis:
Product Analysis:
|
2.00 - 2.50
1.88 - 2.62
|
|
Molybdenum:
|
Heat Analysis:
Product Analysis:
|
0.90 - 1.10
0.85 - 1.15
|
Tensile Test Requirements for Chromium-Molybdenum Alloy
The material shall be tested using a test specimen will confirm to the tensile requirements as outlined in tensile requirements for A387 Grade 22 chromium-molybdenum alloy Class 2 plates above.
Recommended Testing Procedures for Chromium-Molybdenum Alloy
The following requirements and testing procedures (which are not mandatory) are considered suitable for chromium-Molybdenum alloy:
- Vacuum treatment
- Product Analysis
- Additional Tension Test
- Charpy V-Notch Impact Test
- Drop Weight Test
- High Temperature Tension Test
- Ultrasonic Examination
- Magnetic Particle Examination
To find out more about Masteel's services and ASTM A387 Grade 22 Class 2 steel plates which we can supply directly to you please visit Masteel.
This information has been sourced, reviewed and adapted from materials provided by Masteel UK Ltd.
For more information on this source, please visit Masteel UK Ltd