Q500C QT Carbon Steel Plate GB/T 16270 Supplier
What is Q500C QT Carbon Steel Plate GB/T 16270?
Q500C, also searched as GB/T 16270 Q500C, Q500C QT plate, Q500C carbon steel plate, Q500C steel plate and Q500C quenched and tempered plate, is the 500 MPa quality-grade-C grade in GB/T 16270. That standard covers high-strength structural steel plate delivered quenched and tempered. Q is the yield symbol, 500 is the thin-plate minimum yield in MPa, and C is the quality letter for Charpy impact at 0°C.
Q500C sits one step above Q460C. The extra 40 MPa is why equipment builders use it on boom sections, chassis rails and base plates that are too heavy in 460 MPa plate. It is still a QT carbon plate, not a stainless grade and not a pressure-vessel grade. A certificate that only says Q500 under another book does not meet this page.
Quality grade C means the impact test is at 0°C. D is −20°C. E is −40°C. F is −60°C. Q500C is the right letter for temperate fabrication and indoor or mild outdoor service. If the drawing shows winter design at −40°C, the letter is E, not C.
The closest European name is EN 10025-6 S500Q. Both are about 500 MPa QT plate tested at 0°C. S500QL is −40°C and lines up with Q500E. S500QL1 is −60°C and lines up with Q500F. Dual mark only when both books are fully met. See EN 10025-6 steel plate.
SHH STEEL is a global steel mill sourcing partner and steel manufacturer and exporter, mill-direct, China origin. We source Q500C from first-line QT 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 high strength low alloy plates and structural steel plates.
Material Specification
| Specification Element | Requirement | SHH STEEL Compliance |
|---|---|---|
| Plate book | GB/T 16270 Q500C | Confirmed |
| Other search names | Q500C QT plate, Q500C carbon steel plate | Covered |
| Delivery condition | Quenched and tempered | Confirmed |
| Yield, thin plate | 500 MPa min | Confirmed |
| Quality grade | C, impact at 0°C | Confirmed |
| Product analysis | GB/T 222 column when ordered | Confirmed |
| Not the same strength | Q460C or Q550C | Do not substitute |
| 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 S500Q, S500QL and S460Q.
Chemical Composition
Heat analysis is the mill ladle table in GB/T 16270. Product analysis, when ordered, follows GB/T 222. Q500C is a low-alloy QT carbon plate. Mills add Nb, V, Ti or Al for grain refinement, and may add Cr, Ni, Mo or B by thickness. The certificate shows the elements actually used.
Heat Analysis and Product Analysis — GB/T 16270 Q500C
| Element | Heat analysis (%) | Product analysis (%) |
|---|---|---|
| Carbon (C), max | 0.20 | 0.22 |
| Silicon (Si), max | 0.80 | 0.85 |
| Manganese (Mn), max | 1.70 | 1.78 |
| Phosphorus (P), max | 0.025 | 0.030 |
| Sulfur (S), max | 0.015 | 0.018 |
| Copper (Cu), max | 0.50 | 0.55 |
| Chromium (Cr), max | 1.50 | 1.55 |
| Nickel (Ni), max | 2.00 | 2.05 |
| Molybdenum (Mo), max | 0.70 | 0.75 |
| Boron (B), max | 0.005 | 0.006 |
| Vanadium (V), max | 0.12 | 0.13 |
| Niobium (Nb), max | 0.06 | 0.07 |
| Titanium (Ti), max | 0.05 | 0.06 |
| Aluminium (Als), min when used | 0.015 | 0.010 |
Grade C allows a slightly wider phosphorus and sulfur window than grade E or F. That is acceptable at 0°C. It is not a reason to use Q500C on a −40°C drawing. If the file needs product analysis, SHH STEEL prints both columns and the thickness band used for the mechanical test.
Do not treat this chemistry as weathering plate. Do not treat it as S355JR.
Mechanical Properties
Buyers search Q500C mechanical properties, Q500C yield strength, GB/T 16270 Q500C tensile and Q500C impact 0°C.
Tensile and impact — GB/T 16270 Q500C
| Thickness | Yield min | Tensile | Elongation min | Impact |
|---|---|---|---|---|
| ≤ 50 mm | 500 MPa | 590–770 MPa | 17% | 0°C, grade C |
| > 50–100 mm | 480 MPa | 590–770 MPa | 17% | 0°C, grade C |
| > 100–150 mm | 440 MPa | as standard table | 17% | 0°C, grade C |
Impact energy is the average of three longitudinal Charpy V-notch specimens. One value may fall below the table, but not below 70% of that value. A typical production heat is at or above 34 J at 0°C. Write a higher energy on the order if the owner requires it.
Yield steps down with thickness. A 500 MPa name on 20 mm plate is not the minimum on a 120 mm flange. SHH STEEL quotes the thickness band on the offer.
Density is 7.85 g/cm³. Hardness after temper is a mill control, not a design value. Z15, Z25 or Z35 through-thickness tensile is an extra.
Material Comparison
| Grade | Book | Delivery | Yield, thin plate | Impact | Swap? |
|---|---|---|---|---|---|
| Q460C | GB/T 16270 | QT | 460 MPa | 0°C | Lower sister |
| Q500C | GB/T 16270 | QT | 500 MPa | 0°C | This page |
| Q500D | GB/T 16270 | QT | 500 MPa | −20°C | Colder sister |
| Q500E | GB/T 16270 | QT | 500 MPa | −40°C | Colder sister |
| Q550C | GB/T 16270 | QT | 550 MPa | 0°C | Higher sister |
| S500Q | EN 10025-6 | QT | 500 MPa | 0°C | Closest comparison |
| S500QL | EN 10025-6 | QT | 500 MPa | −40°C | No, unless E |
| S460Q | EN 10025-6 | QT | 460 MPa | 0°C | Lower yield |
Equivalent Material Grades
There is no official one-to-one substitute for Q500C. What buyers compare is a 500 MPa QT plate tested at 0°C.
The usual European pair is S500Q. S500QL is colder and closer to Q500E. S460Q is the 460 MPa neighbour. SHH STEEL will not stamp S500Q on a Q500C certificate unless both books are fully met.
In the United States, A572 Grade 65 is near this yield but is not this QT book. A514 is a 100 ksi family. In Japan, SM570 is a welded structural grade, not this plate. In China, a GB/T 1591 Q500 heat is a different delivery route.
| Designation | Country / region | Standard | Notes |
|---|---|---|---|
| Q500C | China | GB/T 16270 | Name on this page |
| Q500D / Q500E / Q500F | China | GB/T 16270 | Colder quality letters |
| Q460C | China | GB/T 16270 | Lower yield sister |
| S500Q | Europe | EN 10025-6 | 0°C QT comparison |
| S500QL | Europe | EN 10025-6 | −40°C, closer to Q500E |
| S460Q | Europe | EN 10025-6 | 460 MPa comparison |
| SM570 | Japan | JIS G3106 | Strength comparison only |
QT Structural Service
Buyers pick Q500C when a welded frame, boom or chassis wants 500 MPa yield, QT delivery and impact at 0°C. Search phrases such as Q500C steel plate, GB/T 16270 Q500C and Q500C QT plate all point here.
It is the wrong plate for a −40°C mine site. That work is Q500E. It is the wrong plate for a 460 MPa file that was sized on Q460C. Raising the grade without a design check can change weld procedure and deflection. It is the wrong plate for a 690 MPa boom. That work is Q690C or Q690E. It is the wrong plate for a pressure vessel. That work sits on ASTM A516 or pressure vessel steel plates. It is the wrong plate for an unpainted weathering girder.
SHH STEEL supplies this plate when the drawing names GB/T 16270 and quality grade C at 500 MPa.
Weldability
Q500C is weldable QT carbon plate. Carbon is controlled, but the plate has already been quenched and tempered. A procedure written for S355JR is not a Q500C procedure. A procedure qualified only on Q460C may be under-matched.
Typical consumables are matching 500–550 MPa low-hydrogen electrodes or wires, qualified on a QT 500 MPa family. E7018-class electrodes are often under-matched if the joint must develop full plate strength. A procedure written for S500Q is the usual starting point.
Preheat follows thickness, hydrogen and the approved WPS. Interpass temperature should stay below the mill temper range, or local yield can drop. After heavy cold forming, a stress relief may be required. The fabricator owns the WPS. SHH STEEL can share mill heat data, product analysis and carbon equivalent for that review.
Heat Treatment and Delivery Condition
Usual delivery from SHH STEEL for Q500C is quenched and tempered. Austenitize typically in the 880–930°C range, quench, then temper in the window that holds 500 MPa yield and the 0°C impact. Exact temperatures stay on the mill process sheet.
Do not order Q500C as as-rolled or TMCP unless the contract leaves GB/T 16270. Stress relief after fabrication, if used, must stay below the original temper temperature.
The certificate lists GB/T 16270 Q500C, heat number, heat analysis, product analysis when ordered, tensile by thickness band, and 0°C impact. Certificates may be EN 10204 3.1 or EN 10204 3.2. Dual marking to S500Q is available only when both books are fully met.
Dimensions
Usual supply range from SHH STEEL for Q500C QT carbon steel plate:
- Thickness: commonly 8 mm – 100 mm, heavier plate to 150 mm by enquiry
- Width: 1500 mm – 3800 mm
- Length: 3000 mm – 12000 mm
Cut-to-size webs, flanges and base plates are available. Browse more sizes on structural steel plates and the products index.
Tolerances
Dimensional limits for Q500C follow GB/T 709 unless the purchase order names another table.
Typical thickness tolerance idea for Q500C QT plate
| Nominal thickness (mm) | Usual minus (mm) | Usual plus (mm) |
|---|---|---|
| 8 – 10 | −0.3 | +0.8 |
| 10 – 20 | −0.4 | +0.9 |
| 20 – 30 | −0.4 | +1.0 |
| 30 – 40 | −0.5 | +1.1 |
| 40 – 50 | −0.5 | +1.2 |
| 50 – 80 | −0.6 | +1.4 |
| 80 – 100 | −0.8 | +1.6 |
Width on 1500–3800 mm plate is commonly held to about ±20–25 mm unless a tighter extra is named. Length on 3000–12000 mm plate is commonly held to about +50 / 0 mm or ±25 mm by mill practice. Flatness after QT follows the agreed class. SHH STEEL will not assume a zero-minus extra on Q500C unless the order says so.
Supplementary Requirements
Q500C already defines 500 MPa yield, QT delivery and 0°C impact. Extra items still have to be written on the purchase order.
Book name. Write GB/T 16270 Q500C. Do not write only Q500C.
Impact. Grade C is 0°C. Write a higher energy if the owner requires it.
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.
Heat-treatment record. QT temperatures when the inspector asks.
Identification. Heat number, Q500C, thickness and mill logo.
Third-party witness. EN 10204 3.2 with SGS, TÜV, BV, ABS or the inspector named
Applications
| Industry | Typical components |
|---|---|
| Construction machinery | Q500C QT booms, frames and bases |
| Mining equipment | Q500C chassis and body plate from SHH STEEL |
| Cranes and port equipment | Q500C webs and flanges |
| Heavy trailers | Q500C longitudinal members |
| Comparison vs S500Q | Q500C next to S500Q |
| Comparison vs S500QL | Q500C next to S500QL |
| Comparison vs Q460C | Q500C next to the 460 MPa sister |
Q500C is the plate for a 500 MPa QT file tested at 0°C. It is the wrong plate for a painted warehouse that can use S355JR. It is the wrong plate for a 690 MPa member.
Supply Capability
SHH STEEL sources Q500C from first-line Chinese QT 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: 10 mm, 12 mm, 16 mm, 20 mm, 25 mm, 30 mm, 32 mm, 40 mm, 50 mm, 60 mm, 80 mm, 100 mm.
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 plate is in yard; standard QT rolling about 35–45 days; 3.2 inspection about 45–60 days.
Why Choose SHH STEEL
SHH STEEL is a global steel mill sourcing partner and steel manufacturer and exporter, mill-direct, China origin. For Q500C that means mill-direct QT price, not a multi-layer stockist mark-up. We buy from mills that already run the 500 MPa quench-and-temper route, so the heat carries the 0°C impact without a second upgrade charge.
Delivery is short when the size is in rolling range: ex-stock 5–7 days, standard heat about 35–45 days, 3.2 inspection about 45–60 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 16270 Q500C, keep the QT route, and do not ship Q460C as Q500C. We will not change C to E on the certificate to win an order, and we will not treat Q500C as S355. If the drawing needs −40°C, we will move the inquiry to Q500E and keep the price on the right grade.
FAQ
- What is Q500C steel plate?
- Q500C in GB/T 16270 is quenched-and-tempered carbon structural plate with 500 MPa minimum yield on thin plate and Charpy impact at 0°C. SHH STEEL supplies this plate worldwide as a global steel mill sourcing partner.
- Is Q500C the same as Q460C?
- No. Both are QT plate tested at 0°C. Q500C yields at 500 MPa. Q460C yields at 460 MPa.
- What does the letter C mean in Q500C?
- Quality grade C means the impact test temperature is 0°C. D is −20°C, E is −40°C, F is −60°C.
- Is Q500C the same as S500Q?
- They are the usual comparison pair: both are about 500 MPa QT plate tested at 0°C. Dual mark only when both books are fully met. S500QL is colder and closer to Q500E.
Conclusion
Q500C QT carbon steel plate to GB/T 16270 is 500 MPa quenched-and-tempered structural plate with impact at 0°C. Whether the inquiry says Q500C, GB/T 16270 Q500C, Q500C QT plate or Q500C carbon steel plate, SHH STEEL as a global steel mill sourcing partner supplies plate with Q500C chemistry, heat and product analysis as ordered, GB/T 709 tolerances and EN 10204 3.1 or 3.2 certification.
SHH STEEL supplies Q500C QT Carbon Steel Plate to the United States, Europe, the Middle East, Africa, Asia and the Americas for work that actually names this grade.
Contact SHH STEEL for mill rolling, QT route, cutting, UT, 3.2 inspection or a worldwide quotation.
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