ASME SA542 Type A Class 3 Steel Plate | SA542 Type A Cl.3 QT Cr-Mo Vessel Plate
What is ASME SA542 Type A Class 3 Steel ?
ASME SA542 Type A Class 3, also written ASME SA542 TYPE A CL.3, is quenched-and-tempered 2.25Cr-1Mo alloy plate under ASME SA-542/SA-542M. The specification covers Type A, B, C, D and E, and Class 1, 2, 3, 4 and 4a. Type A is the open 2.25Cr-1Mo line. Type B uses the same chromium-molybdenum idea with tighter carbon, phosphorus, sulfur, copper, nickel and vanadium. Class 3 sits between the high Classes and the Class 4 / 4a band: 515 MPa yield and 655–795 MPa tensile. SHH STEEL is the supplier, exporter and distributor of this Type and Class. Plate is produced to ASME SA-542/SA-542M.
Buyers write ASME SA542 Type A Class 3, ASME SA542 TYPE A CL.3, SA542 Type A Class 3, SA542 Type A Cl.3, SA542A CL3, SA-542 Type A Class 3 and SA 542 Type A Cl 3. ASTM A542 Type A Class 3 is the companion product spec. A purchase order that only says “SA542 Type A” is incomplete. A purchase order that says “SA542 Grade 22 Class 3” is mixing this book with SA387 Gr.22 Cl.2.
This page is not SA832 22V. SA832 is normalized-and-tempered Cr-Mo-V. It is not SA517 Gr.E. It is not SA537 Cl.2. It is not SA516 Gr.70. Minimum thickness in the specification is about 5 mm. Maximum thickness is limited by the ability of the heat to meet Class 3 after quench and temper.
For Type A, B and C in Class 1, 2 and 3, the minimum tempering temperature is 565 °C. Dual marking SA542 / A542 Type A Class 3 is available from SHH STEEL as mill supplier. Certificates can be EN 10204 3.1 or 3.2. Company scope: China steel Mill Agent-SHH STEEL.
Material Specification
| Specification Element | Requirement | SHH STEEL Compliance |
|---|---|---|
| Type / Class | ASME SA542 Type A Class 3 | Confirmed |
| Product Specification | ASME SA-542/SA-542M | Applied |
| Companion Spec | ASTM A542 Type A Class 3 | Dual cert available |
| General Requirements | ASME SA-20 / ASTM A20 | Applied |
| Process | Quenched and tempered | Confirmed |
| Alloy idea | 2.25Cr-1Mo, Type A residuals | Confirmed |
| Sister N+T spec | SA-832 / A832 | Not this page |
| Supply role | Supplier / exporter / distributor | SHH STEEL |
| Certification | EN 10204 3.1 or 3.2 / third-party | As ordered |
This plate sits in pressure vessel steel plates and next to the ASME SA387 family, not as a substitute. It does not sit with carbon steel plates or ASTM A36 steel plate.
SA-20 still governs marking, testing location, retests and repair rules.
Chemical Composition
ASME SA542 Type A Class 3 / ASME SA542 TYPE A CL.3 uses Type A chemistry. Class only changes strength.
Heat Analysis and Product Analysis — ASME SA542 Type A (typical Table 1 limits)
| Element | Heat Analysis (%) | Product Analysis (%) |
|---|---|---|
| Carbon (C), max | 0.15 | 0.18 |
| Manganese (Mn) | 0.30 – 0.60 | 0.25 – 0.66 |
| Phosphorus (P), max | 0.025 | 0.025 |
| Sulfur (S), max | 0.025 | 0.025 |
| Silicon (Si), max | 0.50 | 0.50 |
| Chromium (Cr) | 2.00 – 2.50 | 1.88 – 2.62 |
| Molybdenum (Mo) | 0.90 – 1.10 | 0.85 – 1.15 |
| Nickel (Ni), max | Per Type A table | Per Type A table |
| Copper (Cu), max | Per Type A table | Per Type A table |
| Vanadium (V), max | Per Type A table | Per Type A table |
Type A is not Type D. Type D adds a vanadium band of about 0.25–0.35% and is 2.25Cr-1Mo-V. Type C and Type E sit on the 3Cr-1Mo-V band, closer in idea to SA387 Gr.21 Cl.2. If the purchase order names Type B residual limits, do not ship Type A and call it close.
SHH STEEL reports heat analysis on every certificate, including Cr, Mo and Type A residuals.
Mechanical Properties
Class 3 is the mid QT line.
Tensile Requirements — ASME SA542 Type A Class 3
| Property | Requirement |
|---|---|
| Yield strength, min | 515 MPa (75 ksi) |
| Tensile strength | 655 – 795 MPa (95 – 115 ksi) |
| Elongation in 50 mm, min | 20% |
| Density | 7.85 g/cm³ |
| Hardness | Not a default substitute for tensile |
Class 1 is 585 MPa yield and 725–860 MPa tensile. Class 2 is 690 / 795–930. Class 4 is 380 / 585–760. Class 4a is 415 / 585–760. Do not stamp Class 3 as Class 1 because a coupon came in high.
Density is 7.85 g/cm³. Notch toughness is commonly added. Write the temperature, energy, location and orientation. Simulated PWHT is common.
Do not treat 515 MPa yield as permission to substitute A516 Grade 70, SA533 Type A Cl.1 or high strength low alloy plates.
Material Comparison
| Grade | Route | Alloy / strength idea | Swap? |
|---|---|---|---|
| SA542 Type A Class 1 | QT 2.25Cr-1Mo | 585 / 725–860 | No |
| SA542 Type A Class 2 | QT 2.25Cr-1Mo | 690 / 795–930 | No |
| SA542 Type A Cl.3 | QT 2.25Cr-1Mo | 515 / 655–795 | This page |
| SA542 Type B Class 3 | QT 2.25Cr-1Mo | Tighter residuals, same Class | No |
| SA542 Type A Class 4a | QT 2.25Cr-1Mo | 415 / 585–760 | No |
| SA387 Gr.22 Cl.2 | Cr-Mo family | Not SA542 QT Class 3 | No |
| SA832 22V | N+T Cr-Mo-V | Not QT Type A | No |
SA299 Gr.A, SA225 Gr.C, SA455 steel plate and SA285 Gr.C are also vessel plates. None of them is ASME SA542 TYPE A CL.3.
QT Cr-Mo Vessel Service
ASME SA542 Type A Class 3 / ASME SA542 TYPE A CL.3 is selected when the vessel wants quenched-and-tempered 2.25Cr-1Mo at the Class 3 strength line and accepts Type A residuals. Typical equipment is high-temperature welded pressure vessels and components written to SA-542 Type A Class 3. Allowable stress comes from ASME Section II Part D after the Code lists this Type and Class.
SHH STEEL supplies this plate as exporter and stockist. It is not nickel low-temp plate like SA203 Gr.A or SA203 Gr.D. It is not layered QT carbon like SA724. It is not SA302 Gr.B. Stainless inquiries belong on ASME SA240 or ASTM A240.
Do not form this plate as if it were as-rolled SA285 Gr.A. Quench-and-temper properties are the product. A later PWHT cycle has to be planned and, when required, simulated on coupons.
Weldability
SA542 Type A Cl.3 is killed, fine-grain 2.25Cr-1Mo at Class 3 strength. Welding is Code welding.
Qualify procedures to ASME Section IX. Use consumables written for 2.25Cr-1Mo QT at 655–795 MPa tensile, not a Class 2 procedure copied down and not an unreviewed SA387 Gr.12 Cl.2 procedure. Hydrogen control, preheat, interpass and PWHT follow the qualified procedure and the vessel specification.
The fabricator owns the WPS. SHH STEEL as supplier can share mill heat data for review.
Heat Treatment
Plates shall be austenitized, quenched in a suitable liquid medium, then tempered. For Type A, B and C in Class 1, 2 and 3, the minimum tempering temperature is 565 °C (1050 °F). Soak is not less than 1.2 min/mm of thickness and not less than ½ hour. Class 4 uses 650 °C. Class 4a uses 675 °C. Do not apply the Class 4a floor to Class 3 and stamp Class 4a.
If the vessel will see a long PWHT, test coupons shall follow a simulated cycle. This is not the SA832 N+T route and not the SA537 Cl.1 heat-treated carbon route. SHH STEEL as mill exporter prints QT, Type A, Class 3, austenitizing and tempering temperatures on the certificate when the mill record carries them.
Delivery Condition
Usual delivery from SHH STEEL as supplier and distributor is quenched-and-tempered ASME SA542 Type A Class 3 / ASME SA542 TYPE A CL.3 plate.
The certificate lists ASME SA542 Type A Class 3 and, when dual certified, ASTM A542 Type A Class 3; heat number; heat analysis including Cr, Mo and Type A residuals; product analysis when ordered; tensile results to the Class 3 table; QT statement; impact and simulated PWHT when ordered. Certificates may be EN 10204 3.1 or EN 10204 3.2.
Dimensions
Usual supply range from SHH STEEL for SA542 Type A Cl.3 QT Cr-Mo vessel plate:
- Thickness: commonly 8 mm – 150 mm, minimum about 5 mm, limited by the ability of the heat to meet Class 3 after QT
- Width: 1500 mm – 4000 mm
- Length: 3000 mm – 12000 mm
- Cut-to-length shells, heads and nest sizes inside those limits
Structural sizes belong on EN 10025-2 or JIS G3106. Weathering plate belongs on EN 10025-5 or Corten A/B. Fine-grain structural belongs on EN 10025-3 or EN 10025-4. QT structural belongs on EN 10025-6.
Tolerances
Dimensional limits follow ASME SA-20. Thickness, width, length, flatness and camber are vessel-plate tolerances. UT to A435 / A577 / A578 is commonly added on reactor plate.
Supplementary Requirements
Most export ASME SA542 Type A Class 3 / ASME SA542 TYPE A CL.3 orders add extras. SHH STEEL as supplier does not assume them.
Charpy details. Temperature, energy, location and orientation.
Simulated PWHT. Same-heat coupons follow the vessel cycle.
NDE. UT to A435 / A577 / A578.
Hydrogen-service extras. When the vessel specification names them.
Third-party. EN 10204 3.2.
Equivalent Material Grades
| Designation | Standard | Notes |
|---|---|---|
| ASME SA542 Type A Class 3 / ASME SA542 TYPE A CL.3 | ASME SA-542/SA-542M | Code name on this page |
| ASTM A542 Type A Class 3 | ASTM A542/A542M | Companion spec |
| SA542 Type B Class 3 | SA-542 | Same Class, tighter residuals |
| SA542 Type A Class 1 / 2 / 4 / 4a | SA-542 | Other Classes |
| SA387 Gr.22 Cl.2 | SA-387 | Related 2.25Cr-1Mo, not this QT Class |
| SA832 22V | SA-832 | N+T Cr-Mo-V |
| ASME SA387 | SA-387 | Related Cr-Mo family |
DIN 17100, ASTM A516, ASME SA515 and ASTM A285 are not SA542 Type A Class 3.
Applications
| Industry | Typical components |
|---|---|
| High-temperature vessels | ASME SA542 Type A Class 3 shells and ASME SA542 TYPE A CL.3 heads |
| QT 2.25Cr-1Mo equipment | SA542 Type A Cl.3 courses |
| Dual-certified export | SA542 / A542 Type A Class 3 plate from SHH STEEL |
| Fabrication | SA542 Type A Cl.3 cut to nest sizes |
Ship plate inquiries belong on shipbuilding steel plates or BV Rules. Weathering inquiries belong on weathering steel plates. Stainless inquiries belong on stainless steel products, JIS G4305 or AISI stainless.
Other vessel comparisons: SA203 Gr.B, SA302 Gr.C, A516 Grade 70, SA533 Type C Cl.2, SA517 Gr.P, SA387 Gr.11 Cl.2.
Why Choose SHH STEEL
SHH STEEL is the supplier, exporter, distributor and stockist of ASME SA-542/SA-542M plate. On ASME SA542 Type A Class 3 / ASME SA542 TYPE A CL.3 that means mill pricing, dual SA542/A542 marking, Type A chemistry, recorded quench and temper at the Class 3 floor, tensile results at 515 MPa yield and 655–795 MPa tensile, 3.1 as standard and 3.2 when specified.
We keep Type and Class on the order. Type A is not Type B and is not Type D. Class 3 is not Class 1 and is not Class 4a. SA542 is not SA387 Gr.22 Cl.2. SA542 is not SA516 Gr.55. SA542 Type A Cl.3 is not SA533 Type C Cl.1. If the drawing names Type B residuals, we will not ship Type A and call it close. If the drawing names N+T Cr-Mo-V, we point the inquiry to SA832.
Company scope: China steel Mill Agent-SHH STEEL.
FAQ
- What names are used for ASME SA542 Type A Class 3 / ASME SA542 TYPE A CL.3?Buyers write ASME SA542 Type A Class 3, ASME SA542 TYPE A CL.3, SA542 Type A Class 3, SA542 Type A Cl.3, SA542A CL3, SA-542 Type A Class 3 and SA 542 Type A Cl 3. SHH STEEL as supplier prints the wording on the purchase order.
- Is ASME SA542 Type A Class 3 the same as ASTM A542 Type A Class 3?Chemistry and tensile limits match. ASME SA-542 is the Code version. ASTM A542 is the product spec. As exporter and mill distributor, SHH STEEL dual-certifies both names when the vessel must be stamped.
- What is the yield strength of SA542 Type A Cl.3?515 MPa minimum. Tensile is 655–795 MPa. Elongation is 20% in 50 mm.
- How is ASME SA542 TYPE A CL.3 different from Type B Class 3?Same Class 3 tensile table and the same 2.25Cr-1Mo idea. Type B tightens carbon, phosphorus, sulfur, copper, nickel and vanadium.
- How is ASME SA542 Type A Class 3 different from Class 1, Class 2 and Class 4a?Class 3 is 515 / 655–795. Class 1 is 585 / 725–860. Class 2 is 690 / 795–930. Class 4a is 415 / 585–760.
- s SA542 Type A Class 3 the same as SA832 22V or SA387 Grade 22?No. SA832 22V is N+T Cr-Mo-V. SA387 Grade 22 is 2.25Cr-1Mo in the SA387 family. SA542 Type A Class 3 is QT 2.25Cr-1Mo at Class 3 strength.
- Who supplies ASME SA542 Type A Class 3?SHH STEEL is the supplier, exporter, distributor and stockist.
- Can SHH STEEL issue EN 10204 3.2 for ASME SA542 Type A Class 3?Yes. EN 10204 3.1 is standard. EN 10204 3.2 is arranged when written on the order.
Conclusion
ASME SA542 Type A Class 3 Steel Plate, also searched as ASME SA542 TYPE A CL.3, is quenched-and-tempered 2.25Cr-1Mo plate under ASME SA-542/SA-542M, with Type A residuals and Class 3 strength. Whether the inquiry says ASME SA542 Type A Class 3, ASME SA542 TYPE A CL.3, SA542 Type A Cl.3 or SA542A CL3, SHH STEEL as supplier, exporter, distributor and stockist supplies plate with Type A chemistry, recorded QT delivery, 515 MPa yield, and EN 10204 3.1 or 3.2 certification.
SHH STEEL is the China mill vendor of ASME SA542 Type A Class 3 / ASME SA542 TYPE A CL.3 QT Cr-Mo Vessel Plate for ASME Section VIII work that actually names this Type and Class.
Contact SHH STEEL for mill rolling, stock inquiry, dual SA542/A542 marking, simulated PWHT testing, 3.2 inspection or a quotation.
ASME SA542 Type A Class 3 Steel Plate, ASME SA542 TYPE A CL.3, SA542 Type A Cl.3, SA542A CL3, SA-542 Type A Class 3, QT Cr-Mo vessel plate, SHH STEEL supplier exporter distributor stockist
Quality Steel Needed? Inquire for Offers
Related Products
