Q390ND Steel Plate GB/T 1591 Supplier

GB/T 1591 Q390ND is normalized high-strength low-alloy plate with 390 MPa minimum yield and −20°C impact. SHH STEEL supplies Q390ND plate mill-direct for bridges, buildings and cold-weather frames that name the N condition. This is not hot-rolled Q390D and not TMCP Q390MD.
Keywords
Q390ND, Q390ND steel plate, GB/T 1591 Q390ND, Q390ND plate, Q390ND supplier, EN 10025-3 S420N, ASTM A572 Gr.55, Q390D, Q390MD
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General Description
Material Specification
Chemical Composition
Mechanical Properties
Material Comparison
Equivalent Material Grades
Structural Service
Weldability
Heat Treatment and Delivery Condition
Dimensions
Tolerances
Supplementary Requirements
Applications
Supply Capability
Global Delivery and Markets
Why Choose SHH STEEL
FAQ
Conclusion

What is Q390ND Steel Plate GB/T 1591?

Q390ND, also searched as GB/T 1591 Q390ND, Q390ND steel plate, Q390ND plate and Q390 ND, is the 390 MPa quality-grade-D grade delivered normalized or normalizing-rolled in GB/T 1591-2018. Q is the yield symbol, 390 is the thin-plate minimum yield in MPa, N is the delivery letter, and D is the quality letter for Charpy impact at −20°C.

The N is the point of this page. Hot-rolled Q390D has no N. Thermomechanical Q390MD has an M. A hot-rolled certificate cannot be stamped ND. A TMCP certificate cannot be stamped ND. Grade B is +20°C and is GB/T 1591 Q390NB. Grade C is 0°C and is GB/T 1591 Q390NC. E is −40°C. Q390 sits between GB/T 1591 Q355ND and GB/T 1591 Q420D. Do not drop a 390 MPa drawing onto a 355 MPa plate, and do not upgrade it to 420 MPa without a price check.

EN 10025 has no S390 letter. The closest higher comparison is EN 10025-3 S420N, a normalized fine-grain grade also tested at −20°C. EN 10025-3 S355N is the lower normalized comparison. EN 10025-2 S355J2 is −20°C and only 355 MPa. On the US side, ASTM A572 Gr.55 is 55 ksi / 380 MPa, one step lower, and it is not an ND twin. JIS G3106 SM520B is the usual Japanese comparison. Dual mark only when both books are fully met. See EN 10025-3 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 Q390ND from first-line structural mills, 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 ElementRequirementSHH STEEL Compliance
Plate bookGB/T 1591-2018 Q390NDConfirmed
Other search namesQ390ND steel plate, Q390 NDCovered
Delivery conditionNormalized or normalizing rolledConfirmed
Yield, ≤ 16 mm390 MPa minConfirmed
Quality gradeD, impact at −20°CConfirmed
Not this pageHot-rolled Q390DDifferent condition
Not this pageTMCP Q390MDDifferent condition
EN comparisonEN 10025-3 S420N is higherComparison, not a swap
US comparisonASTM A572 Gr.55 is 380 MPaNot a twin
Product analysisGB/T 222 column when orderedConfirmed
Supply roleGlobal steel mill sourcing partnerSHH STEEL
CertificationEN 10204 3.1 or 3.2As ordered

Nearby pages that buyers compare, but must not swap blindly, include EN 10025-3 S420N, ASTM A572 Gr.55 and GB/T 1591 Q355ND.

Chemical Composition

Heat analysis is the mill ladle table in GB/T 1591-2018 for normalized Q390. Product analysis, when ordered, follows GB/T 222. Q390ND is a microalloyed HSLA plate. Grade D is tighter on phosphorus and sulfur than grade B or C, because the impact test is at −20°C. Mills may add Nb, V or Ti. The certificate shows the elements actually used.

Heat Analysis and Product Analysis — GB/T 1591 Q390ND, normalized

ElementHeat analysis (%)Product analysis (%)
Carbon (C), max0.180.20
Silicon (Si), max0.500.55
Manganese (Mn), max1.701.80
Phosphorus (P), max0.0300.035
Sulfur (S), max0.0250.030
Niobium (Nb), max0.070.08
Vanadium (V), max0.200.22
Titanium (Ti), max0.200.21
Chromium (Cr), max0.300.35
Nickel (Ni), max0.500.55
Copper (Cu), max0.400.45
Molybdenum (Mo), max0.100.11
Nitrogen (N), max0.0150.017
Aluminium (Als), min when used0.0150.010

Carbon equivalent is limited by thickness in the standard. The N route often has a different CEV window from hot-rolled Q390D. 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 Q460D. A 355 MPa file is GB/T 1591 Q355D, not this grade.

Mechanical Properties

Buyers search Q390ND mechanical properties, Q390ND yield strength, GB/T 1591 Q390ND tensile and Q390ND impact −20°C.

Tensile and impact — GB/T 1591 Q390ND, normalized

ThicknessYield minTensileElongation minImpact
≤ 16 mm390 MPa490–650 MPa20%−20°C, grade D
> 16–40 mm380 MPa490–650 MPa20%−20°C, grade D
> 40–63 mm360 MPa490–650 MPa19%−20°C, grade D
> 63–80 mm350 MPa490–650 MPa19%−20°C, grade D
> 80–100 mm340 MPa490–650 MPa19%−20°C, grade D
> 100–150 mm330 MPa470–620 MPa18%−20°C, grade D

Impact energy is the average of three longitudinal Charpy V-notch specimens, commonly 34 J minimum at −20°C. 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.

Yield steps down with thickness. A 390 MPa name on 12 mm plate is not the minimum on a 40 mm flange. 390 MPa is about 56.5 ksi. ASTM A572 Gr.55 is 55 ksi and is not this book. SHH STEEL quotes the thickness band and the N condition on the offer.

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 D letter.

Material Comparison

GradeBookDeliveryYield, thin plateImpactSwap?
Q390DGB/T 1591-2018Hot rolled390 MPa−20°CDifferent process
GB/T 1591 Q390NBGB/T 1591-2018Normalized390 MPa+20°CWarmer N sister
GB/T 1591 Q390NCGB/T 1591-2018Normalized390 MPa0°CWarmer N sister
Q390NDGB/T 1591-2018Normalized390 MPa−20°CThis page
Q390MDGB/T 1591-2018TMCP390 MPa−20°CDifferent process
GB/T 1591 Q355NDGB/T 1591-2018Normalized355 MPa−20°CLower yield
EN 10025-3 S420NEN 10025-3Normalized420 MPa−20°CHigher comparison
ASTM A572 Gr.55ASTM A572As rolled380 MPaDifferentLower yield

A colder 420 MPa file is GB/T 1591 Q420E. A 460 MPa file is GB/T 1591 Q460D.

Equivalent Material Grades

There is no official one-to-one substitute for Q390ND. What buyers compare is a 390 MPa normalized plate tested at −20°C.

EN 10025 has no S390. EN 10025-3 S355N is lower and also tested at −20°C. EN 10025-3 S420N is higher. EN 10025-2 S355J2 is −20°C and only 355 MPa. In the United States, ASTM A572 Gr.55 is 55 ksi / 380 MPa. ASTM A572 Gr.50 is 50 ksi and is one step lower. ASTM A36 is 36 ksi and is well below this yield. In Japan, JIS G3106 SM520B is the usual comparison. SHH STEEL will not stamp EN 10025-3 S420N or ASTM A572 Gr.55 on a Q390ND certificate unless the purchase order names both books and both tables are met.

DesignationCountry / regionStandardNotes
Q390NDChinaGB/T 1591-2018Name on this page
Q390DChinaGB/T 1591-2018Hot rolled, not this page
GB/T 1591 Q390NCChinaGB/T 1591-2018Normalized, 0°C
Q390MDChinaGB/T 1591-2018TMCP, not this page
GB/T 1591 Q355NDChinaGB/T 1591-2018355 MPa, normalized
EN 10025-3 S420NEuropeEN 10025-3Higher, −20°C normalized
ASTM A572 Gr.55USAASTM A57255 ksi, lower yield
JIS G3106 SM520BJapanJIS G3106Usual Japanese comparison

Structural Service

Buyers pick Q390ND when a bridge, building member or welded fabrication wants about 390 MPa yield, a normalized or normalizing-rolled condition, and impact at −20°C. Search phrases such as Q390ND steel plate and GB/T 1591 Q390ND all point here.

It is the wrong plate when the drawing says hot rolled only. That work is Q390D. It is the wrong plate when the drawing says TMCP. That work is Q390MD. It is the wrong plate for a 0°C file. That work is GB/T 1591 Q390NC. It is the wrong plate for a −40°C file. That work is Q390NE, and the hot-rolled 355 MPa sister is GB/T 1591 Q355E. It is the wrong plate for a 420 MPa file. That work is GB/T 1591 Q420D or GB/T 1591 Q420B. It is the wrong plate for a 460 MPa file. That work is GB/T 1591 Q460C or GB/T 1591 Q460E. 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 D, and the N condition at 390 MPa.

Weldability

Q390ND is a weldable normalized 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 Q390ND. Carbon equivalent on the N route is not the same window as hot-rolled Q390D. A procedure qualified only at 0°C may miss the −20°C coupon.

Typical consumables are matching 55–60 ksi low-hydrogen electrodes or wires. E7018-class electrodes are under-matched if the joint must develop full plate strength. A procedure written for ASTM A572 Gr.55 is a useful strength reference after chemistry and the −20°C coupon are checked. Preheat follows thickness, hydrogen and the approved WPS. Thick plate and restrained joints need more preheat than a 10 mm web.

The fabricator owns the WPS. SHH STEEL can share mill heat data, product analysis and carbon equivalent for that review. Do not use a Q390ND procedure on Q390MD without checking the TMCP carbon equivalent.

Heat Treatment and Delivery Condition

Usual delivery from SHH STEEL for Q390ND is normalized or normalizing rolled. The plate is not hot rolled as Q390D and not thermomechanical rolled as Q390MD.

Normalizing is typically about 880–920°C, followed by air cooling, unless the mill uses a normalizing-rolling route that the standard accepts for the N letter. Do not order Q390ND as quenched and tempered. That route belongs to GB/T 16270. Stress relief after fabrication, if used, should be agreed before cutting.

The certificate lists GB/T 1591 Q390ND, heat number, delivery condition, heat analysis, product analysis when ordered, tensile by thickness band, and −20°C impact. Certificates may be EN 10204 3.1 or EN 10204 3.2. Dual marking to EN 10025-3 S420N is available only when both books are fully met.

Dimensions

Usual supply range from SHH STEEL for Q390ND steel plate:

  • Thickness: commonly 8 mm – 80 mm, heavier plate to 100 mm by enquiry
  • Width: 1500 mm – 3000 mm, wider by enquiry
  • Length: 3000 mm – 12000 mm

Cut-to-size webs, flanges, base plates and gussets are available. Browse more sizes on structural steel plates.

Tolerances

Dimensional limits for Q390ND follow GB/T 709 unless the purchase order names EN 10029 or another table.

Typical thickness tolerance idea for Q390ND plate

Nominal thickness (mm)Usual minus (mm)Usual plus (mm)
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
80 – 100−0.8+1.6

Width on 1500–3000 mm plate is commonly held to about +20 / 0 mm or ±25 mm unless a tighter extra is named. Length on 3000–12000 mm plate is commonly held to about +50 / 0 mm. Flatness follows the agreed class. SHH STEEL will not assume a zero-minus extra on Q390ND unless the order says so.

Supplementary Requirements

Q390ND already defines 390 MPa yield, normalized delivery and −20°C impact. Extra items still have to be written on the purchase order.

Book name. Write GB/T 1591 Q390ND. Do not write only Q390, and do not write Q390D if the mill must stamp N.

Impact. Grade D is −20°C. Write a higher energy if the owner requires it. Do not expect a −40°C result unless the grade is changed to Q390NE.

Delivery condition. Write normalized or normalizing rolled. Write Q390D if hot rolled is enough. Write Q390MD if TMCP is required.

EN or US comparison. Write EN 10025-3 S420N or ASTM A572 Gr.55 only if dual mark is required and both tables are met.

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, Q390ND, thickness and mill logo.

Third-party witness. EN 10204 3.2 with SGS, TÜV, BV, ABS or the inspector named.

Applications

IndustryTypical components
Bridges and towersQ390ND webs and flanges from SHH STEEL
Buildings in cold regionsQ390ND columns, beams and base plates
Construction machineryQ390ND frames where the drawing names N and −20°C
General fabricationQ390ND gussets and connection plates
Comparison vs EN 10025-3Q390ND next to EN 10025-3 S420N
Comparison vs ASTM A572Q390ND next to ASTM A572 Gr.55
Lower yield optionGB/T 1591 Q355ND when 355 MPa is enough

Q390ND is the plate for a 390 MPa normalized file tested at −20°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.

Supply Capability

SHH STEEL sources Q390ND 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: 8 mm, 10 mm, 12 mm, 16 mm, 20 mm, 25 mm, 30 mm, 40 mm, 50 mm, 60 mm, 80 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 N heat is in yard; standard normalizing about 30–45 days; 3.2 inspection about 40–50 days.

Why Choose SHH STEEL

SHH STEEL is a global steel mill sourcing partner and steel manufacturer and exporter, mill-direct, China origin. For Q390ND that means mill-direct structural price, not a multi-layer stockist mark-up. We buy from mills that can actually normalize or normalizing-roll the heat, so the N is on the certificate and not only in the enquiry.

Delivery is short when the size is in rolling range: ex-stock 5–7 days, standard N heat about 30–45 days, 3.2 inspection about 40–50 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 Q390ND, keep the normalized route, and do not ship Q390D or Q390MD as ND. We will not drop the N to save a furnace cycle, and we will not change D to C to save a cold test. If the drawing only needs hot-rolled plate, we will move the inquiry to Q390D and keep the price on the right condition.

FAQ

What is Q390ND steel plate?
Q390ND in GB/T 1591-2018 is normalized or normalizing-rolled high-strength low-alloy plate with 390 MPa minimum yield on thin plate and Charpy impact at −20°C. SHH STEEL supplies this plate worldwide as a global steel mill sourcing partner.
Is Q390ND the same as Q390D?
No. Both yield at 390 MPa and both are tested at −20°C. Q390D is hot rolled. Q390ND is normalized or normalizing rolled.
Is Q390ND the same as Q390NC?
No. Both are normalized. Q390NC is tested at 0°C. Q390ND is tested at −20°C.
Is Q390ND the same as Q390MD?
No. Q390ND is normalized. Q390MD is thermomechanical rolled. Impact letter D is the same temperature. The process is not.
What is the European equivalent of Q390ND?
There is no S390 in EN 10025. EN 10025-3 S420N is the higher normalized comparison at −20°C. EN 10025-3 S355N is the lower comparison. Dual mark only when both books are fully met.
What is the US equivalent of Q390ND?
There is no official ASTM twin. ASTM A572 Grade 55 is 55 ksi / 380 MPa, slightly lower, and it does not carry an ND letter. SHH STEEL does not dual-mark ASTM A572 unless both books are met.

Conclusion

Q390ND steel plate to GB/T 1591 is 390 MPa normalized structural plate with impact at −20°C. It is not hot-rolled Q390D and not TMCP Q390MD. EN 10025 has no S390. ASTM A572 Grade 55 is 380 MPa and is not a substitute. Whether the inquiry says Q390ND, GB/T 1591 Q390ND or Q390ND steel plate, SHH STEEL as a global steel mill sourcing partner supplies plate with Q390ND chemistry, heat and product analysis as ordered, GB/T 709 tolerances and EN 10204 3.1 or 3.2 certification.

SHH STEEL supplies Q390ND Steel Plate to the United States, Europe, the Middle East, Africa, Asia and the Americas for work that actually names the N condition.

Contact SHH STEEL for mill rolling, normalized Q390ND, cutting, UT, 3.2 inspection or a worldwide quotation.

Q390ND, Q390ND steel plate, GB/T 1591 Q390ND, Q390ND plate, Q390ND supplier, SHH STEEL

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