ASME SA533 Type A Class 1 Steel Plate | SA533 Gr.A Cl.1 Mn-Mo-Ni Vessel Plate

ASME SA533 Type A Class 1 is the manganese-molybdenum, quenched-and-tempered vessel grade in ASME SA-533/SA-533M. The current specification lists five Types (A, B, C, D, E) and three Classes (1, 2, 3). Type A is the only Type that is Mn-Mo without a nickel requirement. Types B, C, D and E add nickel. Class 1 is the 550–690 MPa tensile window. As Direct Mill Supply by SHH STEEL, the plate is produced to ASME SA-533/SA-533M.

The same plate is written SA533 Type A Class 1, SA533 Gr.A Cl.1, SA533 Grade A Class 1, SA533GA CL1, SA-533 Type A Cl.1, ASTM A533 Type A Class 1, A533 Gr.A Cl.1 and A/SA533 Type A Class 1. The standard text says Type. Buyers still search Grade. They mean the same plate. Class is the strength line, not a second chemistry.

Do not put nickel in the Type A ladle and call it Type A. If the drawing wants nickel, the Type is B, C, D or E. If the drawing wants Class 2 (620–795 MPa) or Class 3 (690–860 MPa), that is a different Class on the same Type, not a silent upgrade.

This is not normalized Mn-Mo plate like SA302 Gr.A or SA302 Gr.B. SA302 is the same alloy family in the normalized condition. SA533 is quenched and tempered. A 302 heat cannot be recertified as 533 Type A Class 1 without the QT cycle and the Class 1 tensile table.

This is not SA516 Gr.70 or A516 Gr.70. Those pages are fine-grain carbon. It is not SA537 Cl.1. SA537 is heat-treated C-Mn-Si. It is not SA517 Gr.Q. SA517 is a different QT alloy family with different thickness caps. It is not nickel cryogenic plate like SA203 Gr.A or SA203 Gr.D. It is not Cr-Mo like SA387 Gr.22 Cl.2.

The steel shall be killed and shall meet fine austenitic grain practice under ASME SA-20. Plates are quenched and then tempered at not less than 595 °C (1100 °F), with a minimum hold of 0.5 h/in. (1.2 min/mm) and not less than 0.5 h. As-rolled SA533 is crack-sensitive in transit, especially above about 25 mm, and may ship as-rolled only by written agreement.

Current practice normally limits Type A Class 1 to about 300 mm. Class 3 on Types A–D is capped at 65 mm. Minimum nominal thickness is 6.5 mm.

For Code work the plate is used under ASME Section VIII. Dual marking ASME SA533 Type A Class 1 / ASTM A533 Type A Class 1 is available. Certificates can be EN 10204 3.1 or EN 10204 3.2.

When a project is still choosing QT vessel plate, a China mill Agent path through SHH STEEL puts SA533 Type A Cl.1 next to SA302 Gr.A, SA537 Cl.2 and SA517 Gr.B, so the buyer can see whether they need QT Mn-Mo, normalized Mn-Mo, heat-treated carbon or another QT alloy. Company scope: China steel Mill Agent-SHH STEEL.

This plate is a vessel product. It is not structural ASTM A36 steel plate. It is not low-tensile carbon like SA285 Gr.C.

Chemistry for ASME SA533 Type A is the Type table, not the Class table. Class 1, 2 and 3 share Type A chemistry unless a supplementary manganese increase is invoked for Class 2 or 3.

Heat Analysis — ASME SA533 Type A

Product Analysis — SA533 Gr.A / A533 Type A

Type B requires nickel about 0.40–0.70% heat. Type C is higher nickel. Type D is lower nickel. Type A has no nickel line. If a ladle carries intentional nickel in the Type B band, it is not Type A.

For Class 2 or Class 3, the specification allows a higher manganese maximum when Supplementary Requirement S3 is used. That option does not apply automatically to Class 1.

Compare that ladle with SA302 Gr.A (normalized Mn-Mo), SA302 Gr.C (Mn-Mo-Ni), SA387 Gr.11 Cl.2 (Cr-Mo) and SA516 Gr.70 (carbon). None of those tables is SA533 Type A.

If the drawing says ASME SA533 Type A Class 1 or SA533 Gr.A Cl.1, the ladle must sit in the Type A table and the tensile test must sit in the Class 1 window. SHH STEEL reports heat analysis on every certificate and adds product analysis when SA-20 requires it.

Class 1 is the strength line. Type A only tells the alloy.

Tensile Requirements — ASME SA533 Class 1

Class 2 is 620–795 MPa and 485 MPa yield. Class 3 is 690–860 MPa and 570 MPa yield, with a 65 mm cap on Types A–D. Do not ship Class 1 as Class 2.

Density is 7.85 g/cm³. Charpy is not a hidden default. Nuclear and thick-wall work almost always writes impact temperature, location and orientation as extras.

Compare SA537 Cl.1 and SA517 Gr.Q. Overlap on a number is not a substitute.

ASME SA533 Type A Class 1 is selected for welded vessels that need QT Mn-Mo strength without nickel. Allowable stress comes from ASME Section II Part D for SA-533 Type A Class 1.

Typical use is heavy-wall process vessels, drums and shells specified to SA-533 Type A Class 1. Nuclear beltline work more often names Type B. If the drawing says Type B, do not ship Type A.

It is not a replacement for SA387 Gr.91 Cl.2 creep service or SA203 Gr.E nickel low-temp service.

SA533 Gr.A Cl.1 is QT Mn-Mo. Welding is Code welding.

Procedures are qualified to ASME Section IX. Low-hydrogen practice is mandatory. Consumables must match the required joint strength and toughness after any PWHT.

Preheat depends on thickness, restraint, hydrogen and the qualified WPS. Thick Class 1 plate is not a 12 mm carbon fillet. Simulated PWHT of mill coupons should be on the purchase order when the vessel cycle is known.

Do not copy a SA387 Gr.22 Cl.2 or SA517 Gr.Q procedure onto Type A Class 1 without review. The fabricator owns the WPS.

Plates shall be quenched and tempered.

Tempering shall be at a suitable temperature to produce the specified properties, but not less than 595 °C (1100 °F), with a minimum holding time of ½ h/in. (1.2 min/mm) and not less than ½ h.

As-rolled delivery is not the specified condition. As-rolled shipping is crack-sensitive above about 25 mm and requires written agreement.

SHH STEEL reports quench and temper temperatures and holds on the MTC.

Usual delivery is quenched and tempered Type A Class 1 plate.

The certificate lists ASME SA533 Type A Class 1 and, when dual certified, ASTM A533 Type A Class 1; heat number; heat analysis; product analysis when ordered; tensile results to the Class 1 table; QT temperatures; Charpy results when ordered; and supplementary tests.

Certificates may be EN 10204 3.1 or EN 10204 3.2.

Usual supply range from SHH STEEL for SA533 Gr.A Cl.1 Mn-Mo vessel plate:

• Thickness: 6.5 mm – about 300 mm for Class 1 (practice)
• Width: up to about 4000 mm
• Length: up to about 12000 mm

Class 3 is not this page. Class 3 on Type A stops at 65 mm.

Dimensional limits follow ASME SA-20. UT to A435 / A577 / A578 is commonly added on thick QT plate.

Most export ASME SA533 Type A Class 1 orders add extras. SHH STEEL does not assume them.

Charpy details. Temperature, energy, location and orientation. Thick-wall and nuclear-related work almost always writes this.

Simulated PWHT. Same-heat coupons follow the vessel cycle.

NDE. UT to A435 / A577 / A578.

Restricted residuals. When nuclear or high-restraint work specifies them.

Restricted P, S. Tighter than 0.025% when specified.

Third-party. EN 10204 3.2.

For stamping, write ASME SA533 Type A Class 1 or dual SA533 / A533 Type A Class 1. Nearby pages: A302 Gr.A, A537CL1, A517 Gr.A.

Do not use this grade as a silent stand-in for SA203 Gr.B or SA517 Gr.S.

SHH STEEL works as a China Mill Direct Exporter for plates to ASME SA-533/SA-533M. On ASME SA533 Type A Class 1 that means mill pricing, dual SA533/A533 marking, Type A chemistry without a nickel requirement, recorded quench and temper, Class 1 tensile results, 3.1 as standard and 3.2 when specified.

We keep the order on the right Type and Class. Type A is not Type B. Class 1 is not Class 2. SA533 is not SA516 Gr.55. SA533 is not SA285 Gr.A. SA533 Type A Cl.1 is not SA517 Gr.Q. If the drawing names nickel, we point the inquiry to Type B. If it names normalized Mn-Mo, we point it to SA302.

Company scope: China steel Mill Agent-SHH STEEL.

ASME SA533 Type A Class 1 Steel Plate is quenched-and-tempered manganese-molybdenum vessel plate under ASME SA-533/SA-533M. Whether the inquiry says SA533 Type A Class 1, SA533 Gr.A Cl.1, SA533 Grade A Class 1 or A533 Type A Class 1, SHH STEEL supplies plate with Type A chemistry (no nickel requirement), recorded QT, Class 1 tensile results, and EN 10204 3.1 or 3.2 certification.

As a China mill Distributor, SHH STEEL provides ASME SA533 Type A Class 1 / SA533 Gr.A Cl.1 Mn-Mo Vessel Plate for ASME Section VIII work.

Contact SHH STEEL for mill rolling, dual SA533/A533 marking, 3.2 inspection or a quotation.

ASME SA533 Type A Class 1 Steel Plate, SA533 Gr.A Cl.1, SA533 Grade A Class 1, ASTM A533 Type A Class 1, Mn-Mo QT vessel plate, Direct Mill Supply by SHH STEEL