🟧 Product Overview

Q245R, Q345R, and Q370R are the primary pressure vessel steel grades under the Chinese GB 713 and GB 19189 standards. These steels are widely used in boilers, pressure vessels, heat exchangers, and industrial pressure systems requiring reliable elevated‑temperature performance.

• Q245R: General pressure vessel steel with good weldability
• Q345R: Higher strength for medium‑to‑high pressure applications
• Q370R: High‑strength grade for demanding pressure and temperature conditions

They are the most commonly used pressure vessel steels in China and are widely accepted in global projects.

🟧 Standards

• GB 713 – Steel Plates for Boilers and Pressure Vessels
• GB 19189 – High‑Strength Pressure Vessel Steel
• Related Standards: ASTM A516, ASTM A537, DIN 17155, EN 10028, JIS G3103

🟧 International Pressure Vessel Steel Standards Comparison Table

Country	Standard	Common Grades
China	GB 713 / GB 19189	Q245R, Q345R, Q370R
America	ASTM A516 / A515 / A537 / A387 / A203 / A204 / A285 / A202	A516 Gr60/70, A515, A537, A387, A203, A204, A285, A202
Germany	DIN 17155	HII, 19Mn6
Japan	JIS G3103	P235GH, P265GH, P295GH, P355GH
France	NF A 36‑205	A42CP, A48CP
Britain	BS 1501	161‑430A/B
International (EN)	EN 10028	P235GH, P265GH, P355GH

🟧 Available Grades

• Q245R
• Q345R
• Q370R

🟧 Product Specifications & Available Sizes

Dimensions

• Thickness: 3 – 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
3.0 × 1500 × C	5.75 × 1800 × C
3.5 × 1500 × C	5.75 × 2000 × C
3.75 × 1500 × C	7.75 × 2000 × C
4.5 × 1500 × C	7.5–11.75 × 1500 × C

🟧 Chemical Composition (Q345R – typical)

Element	Max (%)
C	0.20
Mn	1.70
P	0.025
S	0.015
Si	0.50
Nb	0.07
V	0.10
Ti	0.20

🟧 Mechanical Properties (Q345R – typical)

Property	Value
Yield Strength	≥ 345 MPa
Tensile Strength	510–650 MPa
Elongation	≥ 20%
Elevated‑Temperature Strength	Good
Weldability	Excellent

🟧 Physical Properties

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

🟧 Manufacturing Processes

• Hot rolling
• Normalizing (optional)
• Pickling
• Leveling
• Slitting / Cutting to length
• Surface oiling

🟧 Primary Industry Usage

• Boilers
• Pressure vessels
• Heat exchangers
• Petrochemical equipment
• Industrial pressure systems
• High‑temperature welded structures

🟧 Why Use Q245R / Q345R / Q370R Pressure Vessel Steel Coil

• Most widely used Chinese pressure vessel steel grades
• Excellent weldability and forming performance
• Stable mechanical properties at elevated temperatures
• Suitable for a wide range of industrial pressure applications

🟧 Why Choose WelSteels

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