Most commonly used steel specifications for Chrome Moly plate are ASME SA387 and ASTM A387
Chemical and mechanical properties of the ASME and ASTM specifications are the same.
Champak Industries supplies Chrome Moly plates to ASME SA387 and ASTM A387 both from stock and, where required by the customer, cut to size and shape. SA387 and A387 are described as a "Standard Specification for Pressure Vessel Plates, Alloy Steel, and Chromium-Molybdenum.
Chrome Moly Plate
ASME SA / ASTM A387 Gr 11 Cl. 2, ASME SA / ASTM A387 Gr 22 Cl. 2, ASME SA / ASTM A387 Gr 5 Cl. 2, ASME SA / ASTM A387 Gr 9 Cl. 2.
Each grade except Grades 21L, 22L, and 91 is available in two classes of tensile strength described as Class 1 and Class 2.
The most regularly specified grades and hence those that are most readily available from stock are Grades 12, 11, 22, 5, 91 and 9 and in most case stock plates will be produced to the tensile requirements of Class 2.
As with all ASME and ASTM pressure vessel steels, Chrome Moly to SA387 and A387 is produced in conformity to SA20 / A20 which outlines the testing and retesting methods and procedures, permissible variations in dimensions and weight, quality and repair of defects, marking, loading, and ordering information.
Same requirements, different designation: ASME adopts ASTM A387 as SA-387, so the requirements match for the edition ASME adopts; the certificate must still show the designation and edition your order calls for. The ASTM title is “Standard Specification for Pressure Vessel Plates, Alloy Steel, Chromium-Molybdenum”.
Nominal chromium and molybdenum content by grade
| GRADE | NOMINAL CR CONTENT (%) | NOMINAL MO CONTENT (%) |
|---|---|---|
| 2 | 0.50 | 0.50 |
| 12 | 1.00 | 0.50 |
| 11 | 1.25 | 0.50 |
| 22, 22L | 2.25 | 1.00 |
| 21, 21L | 3.00 | 1.00 |
| 5 | 5.00 | 0.50 |
| 9, 91 | 9.00 | 1.00 |
Grades in this table: The table covers every A387 grade. Grades 5, 9, 11, 12, 22 and 91 have their own pages below; Grades 2, 21, 21L and 22L can be requested. The “L” grades are low-carbon versions with a single strength level.
ASME SA387 Steel Plates: Quick Buying Information
| Buying item | Information to specify |
|---|---|
| Specification and edition | ASME SA-387 and the ASME Code edition (Section II Part A); state if dual certification to ASTM A387 is required. |
| Grade and class | Grade 5, 9, 11, 12 or 22 in Class 1 or Class 2, or Grade 91 (single strength level). |
| Heat-treatment condition | Normalized and tempered; annealed is permitted for Class 1. Quenched and tempered where the specification allows it. |
| Dimensions | Thickness × width × length in mm and the number of plates. |
| Supplementary requirements | Simulated PWHT, Charpy impact tests, ultrasonic examination or hydrogen-service tests, as your specification requires. |
| Documents and processing | EN 10204 3.1 or 3.2 certificate, inspection agency, cutting drawing and edge preparation. |
Explore Our ASME SA387 Plate Range
Six ASME SA387 grades, each with a Class 1 and a Class 2 product page. Choose the grade from your design temperature and service, then open the class your design calls for.
ASME SA387 Grade 5
5Cr–½Mo plate for high-sulfur refinery service where more chromium is specified.
ASME SA387 Grade 9
9Cr–1Mo plate for higher-chromium elevated-temperature and oxidation service.
ASME SA387 Grade 11
1¼Cr–½Mo plate for refinery and power-plant pressure vessels at elevated temperature.
ASME SA387 Grade 12
1Cr–½Mo plate for boilers and pressure vessels at moderately elevated temperature.
ASME SA387 Grade 22
2¼Cr–1Mo plate for hotter service and hydrogen-service reactors and vessels.
ASME SA387 Grade 91
9Cr–1Mo–V–Nb plate with high creep strength for power and process equipment.
Single strength level: both pages cover the Grade 91 requirements.
ASME SA387, ASTM A387 or Dual Certified?
The chemistry and tensile requirements are the same for the edition ASME adopts. What differs is the designation your design code requires and the edition the certificate must show.
| Order as | Certificate shows | Use when |
|---|---|---|
| ASME SA387 | SA-387 and the ASME Code edition | The boiler or vessel is built to the ASME Code |
| ASTM A387 | A387 and the ASTM edition year | The purchase specification names the ASTM standard |
| Dual certified | Both SA-387 and A387 | One plate must satisfy both, for example stock for several projects |
How to Select the Right Grade and Class
- Design temperature
- Design strength
- Hydrogen and sulfur
- Edition
- PWHT
For ASME code construction, the plate must be certified to SA-387 for the Code edition your vessel is built to. Choose the grade from the design temperature and service, the class from the allowable stresses used in the design (ASME Section II Part D), and decide on simulated PWHT, impact, ultrasonic and hydrogen-service tests before you enquire.
Chemical Requirements
| GR. 2 | GR. 12 | GR. 11 | GR. 22 | GR. 22L | GR. 21 | GR. 21L | GR. 5 | GR. 9 | GR. 91* | |
|---|---|---|---|---|---|---|---|---|---|---|
| C | 0.05-0.21 | 0.05-0.17 | 0.05-0.17 | 0.05-0.15 | 0.10 | 0.05-0.15 | 0.10 | 0.15 | 0.15 | 0.08-0.12 |
| Mn | 0.55-0.80 | 0.40-0.65 | 0.40-0.65 | 0.30-0.60 | 0.30-0.60 | 0.30-0.60 | 0.30-0.60 | 0.30-0.60 | 0.30-0.60 | 0.30-0.60 |
| P | 0.025 | 0.025 | 0.025 | 0.025 | 0.025 | 0.025 | 0.025 | 0.025 | 0.025 | 0.020 |
| S | 0.025 | 0.025 | 0.025 | 0.025 | 0.025 | 0.025 | 0.025 | 0.025 | 0.025 | 0.010 |
| Si | 0.15-0.40 | 0.15-0.40 | 0.50-0.80 | 0.50 | 0.50 | 0.50 | 0.50 | 0.50 | 1.00 | 0.20-0.50 |
| Cr | 0.50-0.80 | 0.80-1.15 | 1.00-1.50 | 2.00-2.50 | 2.00-2.50 | 2.75-3.25 | 2.75-3.25 | 4.00-6.00 | 8.00-10.00 | 8.00-9.50 |
| Mo | 0.45-0.60 | 0.45-0.60 | 0.45-0.65 | 0.90-1.10 | 0.90-1.10 | 0.90-1.10 | 0.90-1.10 | 0.45-0.65 | 0.90-1.10 | 0.85-1.05 |
| V | - | - | - | - | - | - | - | - | 0.04 | 0.18-0.25 |
Reading the chemistry table: Single values are maximums and ranges give both limits (heat analysis, % by mass). The asterisk on “GR. 91*” has no footnote here: Grade 91 also has limits for nickel, niobium, nitrogen, aluminium, titanium and zirconium, which the specification lists. Phosphorus and sulfur limits differ between editions, so the certificate is checked against the edition on your order.
Tensile Requirements For Class 1 Plates
| GRADE | TENSILE (MPA) | YIELD (MPA) | ELONG. (50MM) | REDUC'N OF AREA* |
|---|---|---|---|---|
| 2, 12 | 380 - 550 | 230 min | 22% min | - |
| 11 | 415 - 585 | 240 min | 22% min | - |
| 22, 21, 5, 9 | 415 - 585 | 205 min | 18% min | 40% min |
| 21L, 22L | 415 - 585 | 205 min | 18% min | 40% min |
Reading the tensile tables: The asterisk on “REDUC'N OF AREA*” has no footnote here: 40% applies to flat test specimens, and 45% applies when round specimens are used. Grade 91 does not appear in Class 1 because it has a single strength level, shown in the Class 2 table. Class 1 plate may be supplied annealed.
Tensile Requirements For Class 2 Plates
| GRADE | TENSILE (MPA) | YIELD (MPA) | ELONG. (50 MM) | REDUC'N OF AREA* |
|---|---|---|---|---|
| 2 | 485 - 620 | 310 min | 22% min | - |
| 11 | 515 - 690 | 310 min | 22% min | - |
| 12 | 450 - 585 | 275 min | 22% min | - |
| 22, 21, 5, 9 | 515 - 690 | 310 min | 18% min | 40% min |
| 91 | 585 - 760 | 415 min | 18% min | - |
These are specification minimums and ranges. The mill certificate shows the results for each heat and plate; design allowables come from the applicable code.
Standards and Order References
| Reference | Role in the order |
|---|---|
| ASME SA-387 | Section II Part A material specification used for ASME code construction; the certificate must show SA-387 |
| ASME Section II Part D | Allowable stresses by grade, class and temperature for design calculations |
| ASME Section VIII / I | Pressure-vessel and boiler construction rules that call for SA-387 plate |
| ASME SA-20 | General requirements adopted with SA-387: tolerances, testing, marking and supplementary requirements |
| ASTM A387 / A20 | The ASTM documents SA-387 and SA-20 are adopted from; specify dual certification if both are required |
Plate Sizes, Tolerances and Delivery Condition
- Thicknessup to 100 mm
- Widthup to 2500 mm
- Lengthup to 12000 mm
These are the chrome moly plate dimensions listed on our Chrome Moly Plates page; ask for availability against the exact grade, class and size. Permissible variations in thickness, width, length, flatness and weight follow SA-20. State the heat-treatment condition you require.
Applications and Service Requirements
| Application | Grades to evaluate | Selection input |
|---|---|---|
| Hydroprocessing reactors and separators | Grade 22, Grade 11 | Hydrogen partial pressure, temperature, thickness and PWHT |
| Boiler drums, headers and steam vessels | Grade 11, Grade 12, Grade 22, Grade 91 | Design temperature, creep requirements and code |
| Heat exchanger shells and process vessels | Grade 11, Grade 12 | Process temperature, pressure and forming |
| High-sulfur refinery service | Grade 5, Grade 9 | Sulfur content, temperature and oxidation |
These are material application examples, not a list of supplied projects.
Cut-to-Size Plates, Welding and PWHT
As stated above, ASME SA387 plate can be supplied cut to size and shape. Our cutting services include plasma cutting. Send the grade, class, thickness, drawing, quantity and tolerances, and say whether edges will be bevelled or welded; Cr-Mo edges often need preheating before thermal cutting.
Welding consumables
Matching low-hydrogen consumables are normally used, for example E8018-B2 / ER80S-B2 for Grades 11 and 12, E9018-B3 / ER90S-B3 for Grade 22 and B91-type consumables for Grade 91. The qualified WPS sets the consumable.
Preheat and PWHT
Grades 11 and 12 are ASME P-No. 4, Grade 22 is P-No. 5A, Grades 5 and 9 are P-No. 5B and Grade 91 is P-No. 15E. Preheat and PWHT follow the code and WPS; give us the PWHT cycle if test coupons need simulated PWHT.
Testing, Material Documents and Traceability
State the certificate type and test scope with the RFQ. A mill test certificate for the plate and the company's quality-system certification are different documents.
| Requirement | What to identify in the order |
|---|---|
| Material certificate | EN 10204 3.1 or 3.2 showing designation and edition, grade, class, heat treatment, chemistry and tensile results |
| Simulated PWHT | Supplementary requirement S3 with your PWHT temperature, time and number of cycles |
| Impact and ultrasonic tests | Charpy test temperature and energy (S5); UT standard and acceptance level for thick plate |
| Hydrogen service | Any step-cooling, embrittlement-factor or hardness limits your specification sets |
| Traceability and inspection | Heat and plate number on plate and certificate, transfer to cut pieces, and buyer or third-party inspection |
Review our Quality Policy and include your project inspection requirements in the enquiry.
Why Source ASME SA387 Steel Plates from Champak Industries?
Our Mumbai service centre supplies ASME SA387 plate from stock and, where required, cut to size and shape, with a page for every grade and class. As stated above, the most readily available stock grades are 12, 11, 22, 5, 91 and 9, mostly produced to Class 2 tensile requirements. Ask whether a plate can be certified to both SA-387 and A387 if your project needs dual certification. See SA 387 Chrome Moly Steels for both designations together.
ASME SA387 Plate Price and Quotation
Price depends on the grade, class, thickness, plate size, quantity, heat treatment, supplementary tests, certification (single or dual), cutting, inspection, packing and destination. Send a complete requirement for a quotation stating the price basis, tax/freight treatment and validity.
Domestic Dispatch and Export Requirements
For domestic orders, give the delivery address and unloading requirements. For exports, specify the destination, delivery terms, packing and marking instructions and the shipping documents required, with your required delivery date.
Frequently Asked Questions About ASME SA387 Steel Plates
01What is ASME SA387?
ASME SA-387 is the ASME Boiler and Pressure Vessel Code version of ASTM A387: chromium-molybdenum alloy steel plate for welded boilers and pressure vessels in elevated-temperature service.
02Is ASME SA387 the same as ASTM A387?
For the edition ASME adopts, the chemical and mechanical requirements are the same. The designation on the certificate differs, so order the one your design code requires, or both as dual certification.
03When must I order SA387 rather than A387?
When the vessel or boiler is built to the ASME Code, the material must be certified to the SA specification. Plates certified to both SA-387 and A387 can meet either requirement.
04Which SA387 grades and classes are available?
Grades 5, 9, 11, 12 and 22 in Class 1 and Class 2, and Grade 91 at a single strength level. Each has its own page.
05Which grades are most readily available from stock?
This page lists Grades 12, 11, 22, 5, 91 and 9 as the most readily available, with stock plates mostly produced to Class 2 tensile requirements. Confirm availability for your size.
06Can Class 2 plate be used where Class 1 is specified?
Only if your design and specification allow it. Class 2 has higher strength, but substitutions must be approved against the design code and drawings.
07Where do the allowable design stresses come from?
From ASME Section II Part D, by grade, class and temperature. The tensile tables on this page are material acceptance requirements, not design stresses.
08What does SA-20 cover?
SA-20 (ASTM A20) sets the general requirements for pressure-vessel plate: testing and retesting, permissible variations in dimensions, repair of defects, marking and supplementary requirements such as simulated PWHT.
09Can SA387 plate be cut to size?
Yes. Plates can be supplied cut to size and shape. Send the drawing, thickness, quantity, tolerances and edge preparation.
10How do I obtain a price and delivery offer?
Send the Code edition, grade, class, condition, dimensions, quantity, supplementary tests, cutting needs, destination and required date through the form below, by WhatsApp or by phone.