ASME SA533 Type C Class 2 Steel Plate | SA533 Gr.C Cl.2 Mn-Mo-Ni Vessel Plate

ASME SA533 Type C Class 2 is the highest-nickel manganese-molybdenum-nickel combination in ASME SA-533/SA-533M at the Class 2 strength window. The current specification lists five Types (A, B, C, D, E) and three Classes (1, 2, 3). Type C heat nickel is about 0.70–1.00%. Type B is about 0.40–0.70%. Type D is about 0.20–0.40%. Type A has no nickel requirement. Class 2 is 620–795 MPa tensile and 485 MPa yield. As Direct Mill Supply by SHH STEEL, the plate is produced to ASME SA-533/SA-533M.

The same plate is written SA533 Type C Class 2, SA533 Gr.C Cl.2, SA533 Grade C Class 2, SA533GRCCL2, SA-533 Type C Cl.2, ASTM A533 Type C Class 2 and A533 Gr.C Cl.2. The standard text says Type. Buyers still search Grade C Class 2. They mean the same plate. Do not ship Type B and call it Type C. Do not ship Class 1 and call it Class 2. Do not treat this page as normalized SA302 Gr.C. SA302 Grade C is Mn-Mo-Ni in the normalized condition. SA533 Type C Class 2 is quenched and tempered.

Current practice normally limits Type C Class 2 to about 300 mm. Class 3 on Type C is capped at 65 mm. Minimum nominal thickness is 6.5 mm. Dual marking ASME SA533 Type C Class 2 / ASTM A533 Type C Class 2 is available. Certificates can be EN 10204 3.1 or 3.2. Company scope: China steel Mill Agent-SHH STEEL.

This plate is a vessel product under ASME Section VIII when dual marked. It is not structural ASTM A36 steel plate. It is not fine-grain carbon like SA516 Gr.70 or A516 Gr.70. It is not SA515 Gr.70. It is not SA285 Gr.C or A285 Gr.C.

Chemistry for ASME SA533 Type C is the Type table. Class 1, Class 2 and Class 3 share Type C chemistry unless S3 raises manganese on Class 2 or Class 3.

Heat Analysis — ASME SA533 Type C

Product Analysis — SA533 Gr.C / A533 Type C

A ladle at 0.55% Ni sits in Type B, not Type C. A ladle at 0.30% Ni sits in Type D, not Type C. A ladle with no nickel sits in Type A, not Type C. For Class 2, manganese maximum may rise to 1.60% heat and 1.65% product when S3 is specified. SHH STEEL applies that increase only when the purchase order says S3.

Compare that ladle with SA302 Gr.C, SA302 Gr.B, SA387 Gr.11 Cl.2 and SA516 Gr.60. If the drawing says ASME SA533 Type C Class 2 or SA533 Gr.C Cl.2, the ladle must sit in the Type C nickel window and the tensile test must sit in the Class 2 window. SHH STEEL reports heat analysis on every certificate, including nickel and molybdenum.

Class 2 is the strength line. Type C only tells the alloy.

Tensile Requirements — ASME SA533 Class 2

Class 1 is 550–690 MPa and 345 MPa yield, with 18% elongation. Class 3 is 690–860 MPa and 570 MPa yield, with 16% elongation and a 65 mm cap on Type C. A Class 1 heat cannot be stamped Class 2 because someone wants the higher name. Density is 7.85 g/cm³. Charpy is not a hidden default. Thick-wall Type C Class 2 work almost always writes impact temperature, location and orientation.

Compare SA537 Cl.2 and SA517 Gr.Q. Overlap on a yield number is not a substitute.

Order ASME SA533 Type C Class 2 when the drawing names Type C and Class 2. SHH STEEL does not swap this plate for A516 Gr.70 or A517 Gr.Q.

ASME SA533 Type C Class 2 is selected when the vessel needs QT Mn-Mo-Ni at the Class 2 window and the highest nickel band among Types A–D. Allowable stress comes from ASME Section II Part D for SA-533 Type C Class 2 after dual marking.

Typical use is heavy-wall process vessels, high-pressure drums and dual-certified export plate specified to SA-533 Type C Class 2. If the drawing says Type B Class 2, nickel is lower. If the drawing says Type D Class 2, nickel is lower still. If the drawing says Class 1, tensile and yield both drop. If the drawing says Class 3, tensile rises and thickness is capped at 65 mm.

It is not a replacement for SA387 Gr.22 Cl.2 or SA203 Gr.E. It is not a replacement for SA537 Cl.2 heat-treated carbon.

SA533 Gr.C Cl.2 is QT Mn-Mo-Ni at Class 2 strength with the highest nickel band. Welding is Code welding, not structural fillet practice from ASTM A36 steel plate.

Procedures are qualified to ASME Section IX. Low-hydrogen practice is mandatory. Carbon can sit at 0.25%. Molybdenum is in the 0.45–0.60% heat band. Nickel is in the 0.70–1.00% heat band. Calculate carbon equivalent from the actual ladle, not from a memory of Type B.

Preheat depends on thickness, restraint, hydrogen and the qualified WPS. After welding, many shops want to PWHT. Simulated PWHT of mill coupons should be on the purchase order.

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

Plates shall be quenched and tempered. The steel shall be killed and shall meet fine austenitic grain practice under ASME SA-20.

Tempering shall be at a suitable temperature to produce the specified Class 2 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 data on the MTC.

Do not apply the normalize-only route used for SA302 Gr.C and call the plate SA533 Type C Class 2.

Usual delivery is quenched and tempered Type C Class 2 plate.

The certificate lists ASME SA533 Type C Class 2 and, when dual certified, ASTM A533 Type C Class 2; heat number; heat analysis including Ni and Mo; product analysis when ordered; tensile results to the Class 2 table; QT temperatures; Charpy results when ordered; and supplementary tests. Surface is vessel-plate quality. Shot blasting and shop primer are available.

Certificates may be EN 10204 3.1 or EN 10204 3.2.

Usual supply range from SHH STEEL for SA533 Gr.C Cl.2 Mn-Mo-Ni vessel plate:

• Thickness: 6.5 mm – about 300 mm for Class 2 (current practice on Type C)
• Width: up to about 4000 mm
• Length: up to about 12000 mm

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

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 thick QT plate.

Most export ASME SA533 Type C Class 2 orders add extras. SHH STEEL does not assume them.

S3 manganese increase. Allowed for Class 2 and Class 3. Written on the order or not applied.

Charpy details. Temperature, energy, location and orientation.

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

NDE. UT to A435 / A577 / A578.

Restricted residuals / P / S. When specified.

Third-party. EN 10204 3.2.

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 C Class 2 that means mill pricing, dual SA533/A533 marking, Type C chemistry with nickel in the 0.70–1.00% heat band, recorded quench and temper, Class 2 tensile results at 620–795 MPa and 485 MPa yield, 3.1 as standard and 3.2 when specified.

We keep the order on the right Type and Class. Type C is not Type B, not Type D and not Type A. Class 2 is not Class 1 and is not Class 3. SA533 is not SA516 Gr.55. SA533 is not SA285 Gr.A. SA533 Type C Cl.2 is not SA517 Gr.Q. If the drawing names Type B, we will not ship Type C and call extra nickel an upgrade. If it names normalized Mn-Mo-Ni, we point the inquiry to SA302.

Company scope: China steel Mill Agent-SHH STEEL.

ASME SA533 Type C Class 2 Steel Plate is quenched-and-tempered manganese-molybdenum-nickel vessel plate under ASME SA-533/SA-533M, using the highest nickel band among Types A–D at the Class 2 strength window. Whether the inquiry says SA533 Type C Class 2, SA533 Gr.C Cl.2, SA533 Grade C Class 2 or A533 Type C Class 2, SHH STEEL supplies plate with Type C chemistry, recorded QT, Class 2 tensile results, and EN 10204 3.1 or 3.2 certification.

As a China mill Distributor, SHH STEEL provides ASME SA533 Type C Class 2 / SA533 Gr.C Cl.2 Mn-Mo-Ni 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 C Class 2 Steel Plate, SA533 Gr.C Cl.2, SA533 Grade C Class 2, ASTM A533 Type C Class 2, Mn-Mo-Ni QT vessel plate, Direct Mill Supply by SHH STEEL