Q800F QT Carbon Steel Plate GB/T 16270 Supplier
What is Q800F QT Carbon Steel Plate GB/T 16270?
Q800F, also searched as GB/T 16270 Q800F, Q800F QT plate, Q800F carbon steel plate, Q800F steel plate and Q800F quenched and tempered plate, is the 800 MPa quality-grade-F grade in GB/T 16270. That standard covers high-strength structural steel plate delivered quenched and tempered. Q is the yield symbol, 800 is the thin-plate minimum yield in MPa, and F is the quality letter for Charpy impact at −60°C.
Q800F is the coldest letter in the Q800 family. C is 0°C. D is −20°C. E is −40°C. F is −60°C. About 116 ksi on a US drawing is the same yield number. Buyers use it on arctic frames and any drawing that names −60°C at 800 MPa. A mill that only tested at −40°C cannot stamp F. Not every QT mill will accept F on heavy plate.
EN 10025-6 has no S800 grade. S690QL1 is 690 MPa at −60°C, one step lower. S890QL1 is 890 MPa at −60°C, one step higher. S890QL is −40°C and is warmer. On the US side, A514 Grade Q is 100 ksi / 690 MPa, also one step lower, and it does not carry an F letter. 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 Q800F from first-line QT mills that can run a −60°C route, 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 Q800F | Confirmed |
| Other search names | Q800F QT plate, Q800F carbon steel plate | Covered |
| Delivery condition | Quenched and tempered | Confirmed |
| Yield, thin plate | 800 MPa min | Confirmed |
| Quality grade | F, impact at −60°C | Confirmed |
| EN comparison | S690QL1 lower, S890QL1 higher | Not a twin |
| US comparison | A514 is 690 MPa | Not a twin |
| Product analysis | GB/T 222 column when ordered | Confirmed |
| Not the same letter | Q800E or Q800D | 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 S690QL1, S890QL1 and A514 Gr.Q.
Chemical Composition
Heat analysis is the mill ladle table in GB/T 16270. Product analysis, when ordered, follows GB/T 222. Grade F is the tightest cleanliness letter in the Q800 family, because the impact test is at −60°C. Mills add Nb, V, Ti or Al for grain refinement, and may add Ni, Cr, Mo or B by thickness. Nickel is often used on F heats to hold the cold impact. Boron is common on 800 MPa heats. The certificate shows the elements actually used.
Heat Analysis and Product Analysis — GB/T 16270 Q800F
| Element | Heat analysis (%) | Product analysis (%) |
|---|---|---|
| Carbon (C), max | 0.18 | 0.20 |
| Silicon (Si), max | 0.80 | 0.85 |
| Manganese (Mn), max | 2.00 | 2.08 |
| Phosphorus (P), max | 0.015 | 0.020 |
| Sulfur (S), max | 0.005 | 0.008 |
| 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 |
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 weathering plate. Do not treat it as S355JR.
Mechanical Properties
Buyers search Q800F mechanical properties, Q800F yield strength, GB/T 16270 Q800F tensile and Q800F impact −60°C.
Tensile and impact — GB/T 16270 Q800F
| Thickness | Yield min | Tensile | Elongation min | Impact |
|---|---|---|---|---|
| ≤ 50 mm | 800 MPa | 840–1000 MPa | 13% | −60°C, grade F |
| > 50–100 mm | 780 MPa | 840–1000 MPa | 13% | −60°C, grade F |
| > 100–150 mm | 720 MPa | as standard table | 13% | −60°C, grade F |
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 −60°C test at 800 MPa is harder to hold than a −40°C test. Write the energy on the purchase order if the owner wants a number above the book minimum. Not every QT mill will accept F on plate over 40 mm. SHH STEEL confirms the thickness before promising the letter.
Yield steps down with thickness. An 800 MPa name on 16 mm plate is not the minimum on a 60 mm flange. 800 MPa is about 116 ksi. ASTM A514 is 100 ksi and is not this number. 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? |
|---|---|---|---|---|---|
| Q800C | GB/T 16270 | QT | 800 MPa | 0°C | No |
| Q800D | GB/T 16270 | QT | 800 MPa | −20°C | No |
| Q800E | GB/T 16270 | QT | 800 MPa | −40°C | Warmer sister |
| Q800F | GB/T 16270 | QT | 800 MPa | −60°C | This page |
| Q690F | GB/T 16270 | QT | 690 MPa | −60°C | Lower yield |
| S690QL1 | EN 10025-6 | QT | 690 MPa | −60°C | Lower comparison |
| S890QL1 | EN 10025-6 | QT | 890 MPa | −60°C | Higher comparison |
| A514 Gr.Q | ASTM A514 | QT | 690 MPa | Different | Lower yield |
Q800F Equivalent Material Grades
There is no official one-to-one substitute for Q800F. EN 10025-6 jumps from 690 MPa to 890 MPa. ASTM A514 stops at 100 ksi.
The usual European neighbours at −60°C are S690QL1 and S890QL1. S890QL is warmer. A514 Grade Q is 100 ksi / 690 MPa. A572 Gr.65 is only 65 ksi. SHH STEEL will not stamp S890QL1 or A514 on a Q800F certificate unless the purchase order names both books and both tables are met.
| Designation | Country / region | Standard | Notes |
|---|---|---|---|
| Q800F | China | GB/T 16270 | Name on this page |
| Q800C / Q800D / Q800E | China | GB/T 16270 | Warmer impact letters |
| Q690F | China | GB/T 16270 | Lower yield sister |
| A514 Gr.Q | USA | ASTM A514 | 100 ksi, lower yield |
| A572 Gr.65 | USA | ASTM A572 | 65 ksi, lower yield |
| S690QL1 | Europe | EN 10025-6 | 690 MPa at −60°C |
| S890QL1 | Europe | EN 10025-6 | 890 MPa at −60°C |
| SM570 | Japan | JIS G3106 | Well below this yield |
QT Structural Service
Buyers pick Q800F when a welded frame, boom or chassis wants 800 MPa yield, QT delivery and impact at −60°C. Search phrases such as Q800F steel plate, GB/T 16270 Q800F and Q800F QT plate all point here.
It is the wrong plate for a 0°C file that can use Q800C. It is the wrong plate for a −40°C file that can use Q800E. It is the wrong plate for an 890 MPa arctic boom. That work is Q890F, if the mill can make the letter. It is the wrong plate for a 100 ksi US file. That work is A514 Grade Q. 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 16270 and quality grade F at 800 MPa.
Weldability
Q800F is weldable QT carbon plate, but the joint must keep −60°C toughness. Many heats use boron. A procedure written for S355JR is not a Q800F procedure. A procedure qualified only at −20°C is not enough either.
Typical consumables are matching 800 MPa low-hydrogen electrodes or wires, qualified on a QT 800 MPa family with a −60°C impact coupon. Nickel-bearing wires are common on F-grade joints. E7018-class electrodes are under-matched if the joint must develop full plate strength. A procedure written for S890QL1 is a higher-strength reference. An A514 procedure is a lower-strength reference. Neither is a finished WPS for this grade.
Preheat follows thickness, hydrogen and the approved WPS. Interpass temperature should stay below the mill temper range, or local yield and the −60°C result 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 Q800F is quenched and tempered. Austenitize typically in the 880–930°C range, quench, then temper in the window that holds 800 MPa yield and the −60°C impact. Exact temperatures stay on the mill process sheet. F-grade heats at 800 MPa are not every mill’s standard route.
Do not order Q800F as as-rolled or TMCP unless the contract leaves GB/T 16270. ASTM A514 is not a delivery instruction for this page. Stress relief after fabrication, if used, must stay below the original temper temperature.
The certificate lists GB/T 16270 Q800F, heat number, heat analysis, product analysis when ordered, tensile by thickness band, and −60°C impact. Certificates may be EN 10204 3.1 or EN 10204 3.2. Dual marking to S690QL1 or S890QL1 is available only when both books are fully met.
Dimensions
Usual supply range from SHH STEEL for Q800F QT carbon steel plate:
- Thickness: commonly 8 mm – 40 mm, heavier plate to 50 mm by mill confirmation
- Width: 1500 mm – 3000 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 Q800F follow GB/T 709 unless the purchase order names another table.
Typical thickness tolerance idea for Q800F 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 |
Width on 1500–3000 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 Q800F unless the order says so.
Supplementary Requirements
Q800F already defines 800 MPa yield, QT delivery and −60°C impact. Extra items still have to be written on the purchase order.
Book name. Write GB/T 16270 Q800F. Do not write only Q800F.
Impact. Grade F is −60°C. Write a higher energy if the owner requires it.
EN or US comparison. Write S690QL1, S890QL1 or A514 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.
Heat-treatment record. QT temperatures when the inspector asks.
Identification. Heat number, Q800F, thickness and mill logo.
Third-party witness. EN 10204 3.2 with SGS, TÜV, BV, ABS or the inspector named.
Applications
| Industry | Typical components |
|---|---|
| Arctic equipment | Q800F QT frames tested at −60°C |
| Mining equipment | Q800F chassis plate from SHH STEEL |
| Cranes in cold regions | Q800F webs and flanges |
| High-altitude winter work | Q800F base plates |
| Comparison vs S690QL1 | Q800F next to S690QL1 |
| Comparison vs S890QL1 | Q800F next to S890QL1 |
| Comparison vs A514 | Q800F next to A514 Gr.Q |
Q800F is the plate for an 800 MPa QT file tested at −60°C. It is the wrong plate for a painted warehouse that can use S355JR. It is the wrong plate for an 890 MPa member unless the drawing names that grade.
Supply Capability
SHH STEEL sources Q800F from first-line Chinese QT mills that can run a −60°C route 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, 40 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 F heat is in yard; standard QT rolling with −60°C test about 45–55 days; 3.2 inspection about 55–65 days.
Why Choose SHH STEEL
SHH STEEL is a global steel mill sourcing partner and steel manufacturer and exporter, mill-direct, China origin. For Q800F that means mill-direct QT price, not a multi-layer stockist mark-up on a cold-impact heat. We buy from mills that can actually test at −60°C, so the letter F 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 F heat about 45–55 days, 3.2 inspection about 55–65 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 Q800F, keep the QT route, and do not ship Q800E or A514 as F. We will not change F to E to save a cold test, and we will not treat Q800F as S355. If the drawing only needs −40°C, we will move the inquiry to Q800E and keep the price on the right grade.
FAQ
- What is Q800F steel plate?
- 800F in GB/T 16270 is quenched-and-tempered carbon structural plate with 800 MPa minimum yield on thin plate and Charpy impact at −60°C. SHH STEEL supplies this plate worldwide as a global steel mill sourcing partner.
- Is Q800F the same as Q800E?
- No. Both yield at 800 MPa. Q800E is tested at −40°C. Q800F is tested at −60°C.
- What is the US equivalent of Q800F?
- There is no official ASTM twin at 800 MPa. A514 is 100 ksi / 690 MPa, one step lower, and it does not carry a −60°C F letter. SHH STEEL does not dual-mark A514 unless both books are met.
- Is Q800F the same as S690QL1 or S890QL1?
- Neither. EN 10025-6 has no S800 grade. S690QL1 is lower at the same test temperature. S890QL1 is higher. Dual mark only when both books are fully met.
Conclusion
Q800F QT carbon steel plate to GB/T 16270 is 800 MPa quenched-and-tempered structural plate with impact at −60°C. S690QL1 is lower, S890QL1 is higher, and ASTM A514 is 690 MPa. None of those is a silent substitute. Whether the inquiry says Q800F, GB/T 16270 Q800F, Q800F QT plate or Q800F carbon steel plate, SHH STEEL as a global steel mill sourcing partner supplies plate with Q800F chemistry, heat and product analysis as ordered, GB/T 709 tolerances and EN 10204 3.1 or 3.2 certification.
SHH STEEL supplies Q800F 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, −60°C impact, cutting, UT, 3.2 inspection or a worldwide quotation.
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