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.
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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
|
10 CRMO 910
|
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.
Designation
|
Nominal Chromium Content (%)
|
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.
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.
Element
|
Analysis
|
Chemical Composition (%) inc. Grade & UNS No.
|
|
|
Grade 22 (UNS: K11757)
|
Carbon:
|
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.
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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