Q355ME TMCP Steel Plate GB/T 1591 Supplier
What is Q355ME TMCP Steel Plate GB/T 159
Q355ME, also searched as GB/T 1591 Q355ME, Q355ME steel plate, Q355ME TMCP plate and Q355 ME, is the 355 MPa quality-grade-E grade delivered by thermomechanical controlled process in GB/T 1591-2018. Q is the yield symbol, 355 is the thin-plate minimum yield in MPa, M is the delivery letter, and E is the quality letter for Charpy impact at −40°C.
The M is the point of this page. Hot-rolled GB/T 1591 Q355E has no M. Normalized GB/T 1591 Q355NE has an N. A hot-rolled certificate cannot be stamped ME. A normalized certificate cannot be stamped ME. Grade B is +20°C and is GB/T 1591 Q355MB. Grade C is 0°C and is GB/T 1591 Q355MC. Grade D is −20°C and is GB/T 1591 Q355MD. The full family sits on GB/T 1591. Do not drop a 355 MPa drawing onto a lower grade, and do not upgrade it to GB/T 1591 Q390NE without a price check.
The closest European comparison is EN 10025-4 S355ML, a TMCP fine-grain grade tested colder than −20°C. EN 10025-3 S355NL is normalized and closer to Q355NE. EN 10025-4 S420ML is the next TMCP step up. On the US side, ASTM A572 Gr.50 is 50 ksi / 345 MPa, one step lower, and it is not an ME twin. JIS G3106 SM490B is the usual Japanese comparison. Dual mark only when both books are fully met. See EN 10025-4 and high strength low alloy plates.
SHH STEEL is a global steel mill sourcing partner and steel manufacturer and exporter, mill-direct, China origin. We source Q355ME from first-line structural mills that can actually run the TMCP schedule and hold −40°C impact, print heat analysis and product analysis when ordered, and ship plate to fabricators in the United States, Europe, the Middle East, Southeast Asia, Africa and South America. Related pages include structural steel plates and the products index.
Material Specification
| Specification Element | Requirement | SHH STEEL Compliance |
|---|---|---|
| Plate book | GB/T 1591-2018 Q355ME | Confirmed |
| Other search names | Q355ME steel plate, Q355 ME, Q355ME TMCP | Covered |
| Delivery condition | Thermomechanical controlled process | Confirmed |
| Yield, ≤ 16 mm | 355 MPa min | Confirmed |
| Quality grade | E, impact at −40°C | Confirmed |
| Not this page | Hot-rolled GB/T 1591 Q355E | Different condition |
| Not this page | Normalized GB/T 1591 Q355NE | Different condition |
| EN comparison | EN 10025-4 S355ML | TMCP comparison, not a swap |
| US comparison | ASTM A572 Gr.50 is 345 MPa | Not a twin |
| Product analysis | GB/T 222 column when ordered | Confirmed |
| Supply role | Global steel mill sourcing partner | SHH STEEL |
| Certification | EN 10204 3.1 or 3.2 | As ordered |
Nearby pages that buyers compare, but must not swap blindly, include GB/T 1591 Q355D, GB/T 1591 Q355NE and ASTM A572 Gr.50.
Chemical Composition
Heat analysis is the mill ladle table in GB/T 1591-2018 for TMCP Q355. Product analysis, when ordered, follows GB/T 222. Q355ME is a microalloyed HSLA plate. Grade E is the tightest cleanliness letter on TMCP Q355, because the impact test is at −40°C. Mills may add Nb, V or Ti. The certificate shows the elements actually used. TMCP chemistry is often leaner than a normalized heat of the same yield, because the rolling schedule does part of the grain refinement.
Heat Analysis and Product Analysis — GB/T 1591 Q355ME, TMCP
| Element | Heat analysis (%) | Product analysis (%) |
|---|---|---|
| Carbon (C), max | 0.18 | 0.20 |
| Silicon (Si), max | 0.50 | 0.55 |
| Manganese (Mn), max | 1.60 | 1.70 |
| Phosphorus (P), max | 0.025 | 0.030 |
| Sulfur (S), max | 0.020 | 0.025 |
| Niobium (Nb), max | 0.05 | 0.06 |
| Vanadium (V), max | 0.15 | 0.16 |
| Titanium (Ti), max | 0.05 | 0.06 |
| Chromium (Cr), max | 0.30 | 0.35 |
| Nickel (Ni), max | 0.30 | 0.35 |
| Copper (Cu), max | 0.40 | 0.45 |
| Molybdenum (Mo), max | 0.10 | 0.11 |
| Nitrogen (N), max | 0.015 | 0.017 |
| Aluminium (Als), min when used | 0.015 | 0.010 |
Carbon equivalent is limited by thickness in the standard. The M route often has a lower CEV window than hot-rolled GB/T 1591 Q355E. If the purchase order writes product analysis, SHH STEEL prints both columns and the thickness band used for the tensile test. Do not treat this chemistry as quenched-and-tempered GB/T 16270 Q460E. A warmer hot-rolled file is GB/T 1591 Q355C, not this grade.
Mechanical Properties
Buyers search Q355ME mechanical properties, Q355ME yield strength, GB/T 1591 Q355ME tensile and Q355ME impact −40°C.
Tensile and impact — GB/T 1591 Q355ME, TMCP
| Thickness | Yield min | Tensile | Elongation min | Impact |
|---|---|---|---|---|
| ≤ 16 mm | 355 MPa | 470–630 MPa | 22% | −40°C, grade E |
| > 16–40 mm | 345 MPa | 470–630 MPa | 22% | −40°C, grade E |
| > 40–63 mm | 335 MPa | 470–630 MPa | 21% | −40°C, grade E |
| > 63–80 mm | 325 MPa | 470–630 MPa | 21% | −40°C, grade E |
| > 80–100 mm | 315 MPa | 470–630 MPa | 20% | −40°C, grade E |
| > 100–150 mm | 295 MPa | 450–600 MPa | 20% | −40°C, grade E |
Impact energy is the average of three longitudinal Charpy V-notch specimens, commonly 27 J to 34 J minimum at −40°C, depending on the ordered edition and thickness. One value may fall below the table, but not below 70% of that value. Write a higher energy on the order if the owner requires it. Not every TMCP heat will hold E on very thick plate. SHH STEEL confirms the thickness before promising the letter.
Yield steps down with thickness. A 355 MPa name on 12 mm plate is not the minimum on a 40 mm flange. 355 MPa is about 51.5 ksi. ASTM A572 Gr.50 is 50 ksi and is not this book. Density is 7.85 g/cm³. Hardness is not a design value for this grade. Z15, Z25 or Z35 through-thickness tensile is an extra, not part of the E letter.
Material Comparison
| Grade | Book | Delivery | Yield, thin plate | Impact | Swap? |
|---|---|---|---|---|---|
| GB/T 1591 Q355E | GB/T 1591-2018 | Hot rolled | 355 MPa | −40°C | Different process |
| GB/T 1591 Q355NE | GB/T 1591-2018 | Normalized | 355 MPa | −40°C | Different process |
| GB/T 1591 Q355MD | GB/T 1591-2018 | TMCP | 355 MPa | −20°C | Warmer M sister |
| Q355ME | GB/T 1591-2018 | TMCP | 355 MPa | −40°C | This page |
| GB/T 1591 Q390NE | GB/T 1591-2018 | Normalized | 390 MPa | −40°C | Higher yield |
| EN 10025-4 S355ML | EN 10025-4 | TMCP | 355 MPa | −50°C | Closest comparison |
| EN 10025-3 S355NL | EN 10025-3 | Normalized | 355 MPa | −50°C | Different process |
| ASTM A572 Gr.50 | ASTM A572 | As rolled | 345 MPa | Different | Lower yield |
A warmer hot-rolled file is GB/T 1591 Q355B. A 420 MPa file is GB/T 1591 Q420E.
Equivalent Material Grades
There is no official one-to-one substitute for Q355ME. What buyers compare is a 355 MPa TMCP plate tested at −40°C.
EN 10025-4 S355ML is the closest process comparison and is tested colder. EN 10025-3 S355NL is normalized and closer to GB/T 1591 Q355NE. EN 10025-3 S355N is only −20°C. EN 10025-2 S355JR is +20°C and as-rolled, closer to GB/T 1591 Q355B. In the United States, ASTM A572 Gr.50 is 50 ksi / 345 MPa. ASTM A36 is 36 ksi and is well below this yield. In Japan, JIS G3106 SM490B is the usual comparison. SHH STEEL will not stamp EN 10025-4 S355ML or ASTM A572 Gr.50 on a Q355ME certificate unless the purchase order names both books and both tables are met.
| Designation | Country / region | Standard | Notes |
|---|---|---|---|
| Q355ME | China | GB/T 1591-2018 | Name on this page |
| GB/T 1591 Q355E | China | GB/T 1591-2018 | Hot rolled, not this page |
| GB/T 1591 Q355NE | China | GB/T 1591-2018 | Normalized, not this page |
| GB/T 1591 Q355MD | China | GB/T 1591-2018 | TMCP, −20°C |
| EN 10025-4 S355ML | Europe | EN 10025-4 | TMCP comparison |
| EN 10025-3 S355NL | Europe | EN 10025-3 | Normalized comparison |
| ASTM A572 Gr.50 | USA | ASTM A572 | 50 ksi, lower yield |
| JIS G3106 SM490B | Japan | JIS G3106 | Usual Japanese comparison |
Structural Service
Buyers pick Q355ME when a bridge, building member or welded fabrication wants about 355 MPa yield, a TMCP condition, and impact at −40°C. Search phrases such as Q355ME steel plate and GB/T 1591 Q355ME all point here. The family index is GB/T 1591.
It is the wrong plate when the drawing says hot rolled only. That work is GB/T 1591 Q355E. It is the wrong plate when the drawing says normalized. That work is GB/T 1591 Q355NE. It is the wrong plate for a −20°C file. That work is GB/T 1591 Q355MD, and the hot-rolled sister is GB/T 1591 Q355D. It is the wrong plate for a 0°C file. That work is GB/T 1591 Q355MC. It is the wrong plate for a +20°C file. That work is GB/T 1591 Q355MB. It is the wrong plate for a 390 MPa file. That work is GB/T 1591 Q390NC or GB/T 1591 Q390NE. It is the wrong plate for a 420 MPa file. That work is GB/T 1591 Q420NB or GB/T 1591 Q420NE. It is the wrong plate for a 460 MPa file. That work is GB/T 1591 Q460C or GB/T 1591 Q460NE. It is the wrong plate for a pressure vessel. That work sits on ASTM A516 or pressure vessel steel plates.
SHH STEEL supplies this plate when the drawing names GB/T 1591, quality grade E, and the M condition at 355 MPa.
Weldability
Q355ME is a weldable TMCP HSLA structural plate. Carbon is controlled, and many heats use Nb, V or Ti. A procedure written for ASTM A36 is not a finished WPS for thick Q355ME. Carbon equivalent on the M route is often lower than hot-rolled GB/T 1591 Q355E, which helps the root pass, but the TMCP microstructure still needs a qualified procedure. A procedure qualified only at −20°C may miss the −40°C coupon.
Typical consumables are matching 50 ksi low-hydrogen electrodes or wires. E7018-class electrodes are common when the joint does not have to develop the full plate strength. A procedure written for ASTM A572 Gr.50 is a useful strength reference after chemistry and the −40°C coupon are checked. Preheat follows thickness, hydrogen and the approved WPS. Heat input should stay inside the mill window. A very high heat input can soften the TMCP zone next to the weld.
The fabricator owns the WPS. SHH STEEL can share mill heat data, product analysis and carbon equivalent for that review. Do not use a Q355ME procedure on GB/T 1591 Q355NE without checking the normalized carbon equivalent. Do not use it on GB/T 1591 Q460ND either. That plate is a different yield and a different delivery letter.
Heat Treatment and Delivery Condition
Usual delivery from SHH STEEL for Q355ME is thermomechanical controlled process. The plate is not hot rolled as GB/T 1591 Q355E and not normalized as GB/T 1591 Q355NE.
TMCP combines controlled rolling and accelerated cooling. Finish rolling is held in the non-recrystallization range, then the plate is cooled on the run-out table to a finish temperature the mill records. Do not order Q355ME as quenched and tempered. That route belongs to GB/T 16270. Stress relief after fabrication, if used, should be agreed before cutting, because a high temper can move the TMCP properties.
The certificate lists GB/T 1591 Q355ME, heat number, delivery condition, heat analysis, product analysis when ordered, tensile by thickness band, and −40°C impact. Certificates may be EN 10204 3.1 or EN 10204 3.2. Dual marking to EN 10025-4 S355ML is available only when both books are fully met.
Dimensions
Usual supply range from SHH STEEL for Q355ME steel plate:
- Thickness: commonly 6 mm – 60 mm, heavier plate to 80 mm by mill confirmation
- Width: 1500 mm – 3200 mm, wider by enquiry
- Length: 3000 mm – 14000 mm
Cut-to-size webs, flanges, base plates and gussets are available. Browse more sizes on structural steel plates.
Tolerances
Dimensional limits for Q355ME follow GB/T 709 unless the purchase order names EN 10029 or another table.
Typical thickness tolerance idea for Q355ME plate
| Nominal thickness (mm) | Usual minus (mm) | Usual plus (mm) |
|---|---|---|
| 6 – 8 | −0.3 | +0.6 |
| 8 – 15 | −0.3 | +0.8 |
| 15 – 25 | −0.4 | +0.9 |
| 25 – 40 | −0.5 | +1.1 |
| 40 – 60 | −0.6 | +1.3 |
| 60 – 80 | −0.7 | +1.5 |
Width on 1500–3200 mm plate is commonly held to about +20 / 0 mm or ±25 mm unless a tighter extra is named. Length on 3000–14000 mm plate is commonly held to about +50 / 0 mm. Flatness follows the agreed class. TMCP plate can hold a tighter flatness than a heavy normalized plate of the same thickness, but SHH STEEL will not assume a zero-minus extra on Q355ME unless the order says so.
Supplementary Requirements
Q355ME already defines 355 MPa yield, TMCP delivery and −40°C impact. Extra items still have to be written on the purchase order.
Book name. Write GB/T 1591 Q355ME. Do not write only Q355, and do not write Q355E if the mill must stamp M. The family page is GB/T 1591.
Impact. Grade E is −40°C. Write a higher energy if the owner requires it.
Delivery condition. Write thermomechanical controlled process. Write GB/T 1591 Q355E if hot rolled is enough. Write GB/T 1591 Q355NE if normalized is required.
EN or US comparison. Write EN 10025-4 S355ML or ASTM A572 Gr.50 only if dual mark is required and both tables are met. Do not treat EN 10025-4 S355M as a −40°C grade.
Product analysis. Write it if the file needs the second chemistry column.
Through-thickness. Z15, Z25 or Z35 when the joint is loaded through the thickness.
NDE. UT to GB/T 2970 or the named class.
Identification. Heat number, Q355ME, thickness and mill logo.
Third-party witness. EN 10204 3.2 with SGS, TÜV, BV, ABS or the inspector named.
Applications
| Industry | Typical components |
|---|---|
| Cold-region bridges | Q355ME webs and flanges from SHH STEEL |
| Outdoor structures | Q355ME columns and base plates tested at −40°C |
| Construction machinery | Q355ME frames where the drawing names M and −40°C |
| General fabrication | Q355ME gussets and connection plates |
| Comparison vs EN 10025-4 | Q355ME next to EN 10025-4 S355ML |
| Comparison vs ASTM A572 | Q355ME next to ASTM A572 Gr.50 |
| Higher yield option | GB/T 1591 Q420ND when 420 MPa is required |
Q355ME is the plate for a 355 MPa TMCP file tested at −40°C. It is the wrong plate for a painted weathering facade that needs corten. It is the wrong plate for a 690 MPa QT boom under GB/T 16270. A colder 460 MPa normalized file is GB/T 1591 Q460NC or GB/T 1591 Q460NE.
Supply Capability
SHH STEEL sources Q355ME from first-line Chinese structural mills and ships it on worldwide terms. Partner mills include Wuyang (Wugang), Angang, Shougang, Hanye, Anyang Iron and Steel, Baosteel, Xinyu, Xingcheng and other qualified mills when the size requires it.
Mill test certificates are issued to EN 10204 3.1 as standard. EN 10204 3.2 is arranged when the order names a third-party hold point.
Usual rolling thickness: 6 mm, 8 mm, 10 mm, 12 mm, 16 mm, 20 mm, 25 mm, 30 mm, 40 mm, 50 mm, 60 mm. Heavier plate is confirmed before order.
Processing: CNC or flame cutting, bevel, flattening, shot blast, UT to the named class.
Trade terms: FOB Shanghai main, CIF destination available. Payment: TT, LC, or TT + LC.
Ocean time from Shanghai: US West 14–18 days; US Gulf 28–35 days; Rotterdam / Antwerp 28–35 days; Jebel Ali 18–25 days; Singapore 7–12 days; other ports quoted.
Third-party: SGS, TÜV, BV, ABS, CCS, GL, VL, DNV, RINA, NK, KR, or the inspector named.
Global Delivery and Markets
SHH STEEL is a global steel mill sourcing partner with mill partnerships in China. We supply GB, ASTM, ASME, EN, DIN and JIS steel to buyers in the United States, Europe, the Middle East, Southeast Asia, Africa and South America. Origin is mill-direct, China origin.
SHH STEEL has supplied steel plates to the USA, Mexico, Argentina, Peru, El Salvador, Spain, Netherlands, Germany, UAE, Saudi Arabia, South Africa, India, Thailand, Singapore, Vietnam, the Philippines, Japan and Korea.
Typical lead time: ex-stock 5–7 days when an E heat is in yard; standard TMCP with −40°C test about 25–40 days; 3.2 inspection about 35–45 days.
Why Choose SHH STEEL
SHH STEEL is a global steel mill sourcing partner and steel manufacturer and exporter, mill-direct, China origin. For Q355ME that means mill-direct structural price, not a multi-layer stockist mark-up. We buy from mills that can actually run the TMCP schedule and test at −40°C, so the M and the E are both on the certificate.
Delivery is short when the size is in rolling range: ex-stock 5–7 days, standard ME heat about 25–40 days, 3.2 inspection about 35–45 days. Cutting, bevel and UT can run in the same window. FOB Shanghai is the main term. CIF to US West, US Gulf, Rotterdam, Jebel Ali and Singapore is quoted on the same file.
Experience on this grade is simple: print GB/T 1591 Q355ME, keep the TMCP route, and do not ship GB/T 1591 Q355E or GB/T 1591 Q355NE as ME. We will not drop the M to save a cooling cycle, and we will not change E to D to save a cold test. If the drawing only needs hot-rolled plate, we will move the inquiry to Q355E and keep the price on the right condition. If the drawing needs 420 MPa normalized plate, we will move it to GB/T 1591 Q420NC or GB/T 1591 Q420ND.
FAQ
- What is Q355ME steel plate?
- Q355ME in GB/T 1591-2018 is thermomechanical controlled process high-strength low-alloy plate with 355 MPa minimum yield on thin plate and Charpy impact at −40°C. SHH STEEL supplies this plate worldwide as a global steel mill sourcing partner.
- Is Q355ME the same as Q355E?
- No. Both yield at 355 MPa and both are tested at −40°C. Q355E is hot rolled. Q355ME is TMCP.
- Is Q355ME the same as Q355NE?
- No. Q355ME is thermomechanical rolled. Q355NE is normalized or normalizing rolled. Impact letter E is the same temperature. The process is not.
- Is Q355ME the same as Q355MD?
- No. Both are TMCP. Q355MD is tested at −20°C. Q355ME is tested at −40°C.
- What is the European equivalent of Q355ME?
- The nearest comparison is EN 10025-4 S355ML, which is TMCP and tested colder than −20°C. EN 10025-3 S355NL is the normalized comparison. Dual mark only when both books are fully met.
- What is the US equivalent of Q355ME?
- There is no official ASTM twin. ASTM A572 Grade 50 is 50 ksi / 345 MPa, slightly lower, and it does not carry an ME letter. SHH STEEL does not dual-mark ASTM A572 unless both books are met.
- hat thickness can SHH STEEL supply?
- Common supply is 6 mm to 60 mm. Plate to 80 mm is confirmed with the mill before order. Yield on plate over 16 mm is lower than the 355 MPa thin-plate number.
- Can SHH STEEL ship Q355ME to the USA, Europe or the Middle East?
- Yes. SHH STEEL quotes FOB Shanghai and CIF to US West, US Gulf, Rotterdam, Jebel Ali, Singapore and other major ports.
Conclusion
Q355ME steel plate to GB/T 1591 is 355 MPa TMCP structural plate with impact at −40°C. It is not hot-rolled GB/T 1591 Q355E and not normalized GB/T 1591 Q355NE. The nearest European process comparison is EN 10025-4 S355ML. ASTM A572 Grade 50 is 345 MPa and is not a substitute. Whether the inquiry says Q355ME, GB/T 1591 Q355ME or Q355ME TMCP plate, SHH STEEL as a global steel mill sourcing partner supplies plate with Q355ME chemistry, heat and product analysis as ordered, GB/T 709 tolerances and EN 10204 3.1 or 3.2 certification.
SHH STEEL supplies Q355ME Steel Plate to the United States, Europe, the Middle East, Africa, Asia and the Americas for work that actually names the M condition. The grade family is listed on GB/T 1591.
Contact SHH STEEL for mill rolling, −40°C impact, cutting, UT, 3.2 inspection or a worldwide quotation.
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