🟧 Product Overview

Q235, Q275, and Q355 Structural Carbon Steel Coils are widely used hot‑rolled structural steels under the GB/T700 and GB/T1591 standards. Q235B is a mild structural steel with excellent weldability, Q275 provides moderate strength, and Q355 offers higher strength for demanding structural applications.

These grades are commonly used in construction, machinery manufacturing, steel structures, and general engineering applications. International equivalents include ASTM A36 / A572 and EN S235JR / S355JR.

🟧 Standards

• GB/T700 – Q235B Structural Steel
• GB/T1591 – Q275 / Q355B/C/D/E Structural Steel
• ASTM A36 / A572 (Equivalent)
• EN 10025‑2 S235JR / S355JR (Equivalent)

Structural Carbon Steel Standard – International Comparison Table

Country	Standard	Common Grades
China	GB/T 700 / GB/T 1591	Q235B, Q275, Q355B/C/D/E
America	ASTM A36 / A572 / A633 / A656	A36, A572 Gr50, A633, A656
Germany	DIN 17100	ST37‑2, ST52‑3
Japan	JIS G3101	SS400, SS490, SS540
France	NF EN 10025	S235JR, S275JR, S355JR
Britain	BS EN 10025	S235JR, S275JR, S355JR
International (EN)	EN 10025‑2	S235 / S275 / S355

🟧 Available Grades

• Q235B
• Q275
• Q355B
• Q355C
• Q355D
• Q355E

🟧 Product Specifications & Available Sizes

Dimensions

(International standard display — not affected by Regular Sizes)

• Thickness: 1.8 – 20 mm
• Width: 1000 – 2000 mm
• Coil ID: 508 mm / 610 mm
• Coil OD: 900 – 2000 mm
• Coil Weight: 3 – 15 MT

Regular Sizes (mm)

Size	Size
1.8 × 1250 × C	4.5 × 1500 × C
2.0 × 1250 × C	4.75 × 1500 × C
2.5 × 1250 × C	5.5 × 1500 × C
2.75 × 1250 × C	5.75 × 1500 × C
2.75 × 1500 × C	7.5–11.75 × 1500 × C
3.0 × 1500 × C	5.75 × 1800 × C
3.5 × 1500 × C	5.75 × 2000 × C
3.75 × 1500 × C	7.75 × 2000 × C

🟧 Chemical Composition (typical)

Q235B

Element	Max (%)
C	0.17
Mn	1.40
P	0.040
S	0.040
Si	0.35

Q275

Element	Max (%)
C	0.21
Mn	1.50
P	0.040
S	0.040
Si	0.35

Q355B/C/D/E

Element	Max (%)
C	0.20
Mn	1.60
P	0.035
S	0.035
Si	0.55

🟧 Mechanical Properties

Q235B

Property	Value
Yield Strength	≥ 235 MPa
Tensile Strength	370–500 MPa
Elongation	≥ 26%

Q275

Property	Value
Yield Strength	≥ 275 MPa
Tensile Strength	410–550 MPa
Elongation	≥ 23%

Q355B/C/D/E

Property	Value
Yield Strength	≥ 355 MPa
Tensile Strength	470–630 MPa
Elongation	≥ 20%

🟧 Physical Properties

• Density: 7.85 g/cm³
• Modulus of elasticity: 200 GPa
• Thermal expansion: 12×10⁻⁶ /K

🟧 Manufacturing Processes

• Hot rolling
• Pickling
• Leveling
• Slitting / Cutting to length
• Surface oiling

🟧 Primary Industry Usage

• Construction and building structures
• Machinery manufacturing
• Steel frames and beams
• General engineering components
• Fabricated structural parts
• Equipment manufacturing

🟧 Why Use Q235 / Q275 / Q355 Structural Carbon Steel Coil

• Excellent weldability and forming performance
• Reliable mechanical strength for structural applications
• Suitable for both mild and high‑strength structural needs
• Widely recognized Chinese structural steel grades

🟧 Why Choose WelSteels

• Full range of structural carbon steel coils
• Consistent dimensional accuracy
• Custom coil cutting and slitting
• SGS / BV inspection available
• Export‑grade seaworthy packaging
• Reliable delivery for global projects