Choosing the right steel tube standard is not just a technical decision—it directly affects project safety, compliance, and cost. With multiple international standards such as GB/T (China), EN (Europe), and ASTM (USA), buyers often wonder: Which one should I use for my project?
This article explains the differences between GB/T, EN, and ASTM standards for steel tubes, compares their scope and requirements, and offers guidance on how to select the right one.
Understanding the Three Major Standards
| Standard | Region | Focus | Typical Application |
|---|---|---|---|
| GB/T | China | Seamless & welded tubes for structural and mechanical purposes | Machinery, OEM, construction in Asia |
| EN | Europe | Hot finished or cold drawn hollow sections for structural use | Civil engineering, bridges, CE projects |
| ASTM | USA | Carbon & alloy steel pipes/tubes for structural or mechanical use | Construction, oil & gas, North America |
📌 Related reading: GB/T 8162 vs EN 10210
Dimensional Requirements
- GB/T – Wide size range (OD 10–720 mm, WT 1–30 mm); supports seamless and welded; more flexibility for non-standard shapes.
- EN – Strictly defined tolerances for square/rectangular tubes; OD 21.3–508 mm; WT 1.5–100 mm.
- ASTM – Covers round, square, and rectangular; OD 0.5–20 in (12.7–508 mm); emphasis on standard Hollow Structural Sections (HSS).
If your project requires custom cross-sections or sharp corners, GB/T standards are often the most practical choice.
Material Grades
- GB/T (e.g., GB/T 1591, GB/T 8162): Q235, Q345, Q460, Q550, Q690 → wide strength range (235–690 MPa).
- EN (e.g., EN 10025, EN 10210): S235, S275, S355, S420, S460 → emphasizes weldability & impact resistance.
- ASTM (e.g., ASTM A500, ASTM A53): Grades A, B, C, D → focus on carbon steels for structural HSS and pressure pipes.
Key difference: EN grades include suffixes (J0, J2, K2) to show impact toughness at different temperatures—important for cold regions.
Mechanical Properties
| Standard | Yield Strength (MPa) | Tensile Strength (MPa) | Impact Test |
|---|---|---|---|
| GB/T (Q345D) | ≥345 | 470–630 | Optional |
| EN (S355J2H) | ≥355 | 470–630 | Mandatory: 27J @ -20°C |
| ASTM A500 Gr. C | ≥345 | 400–525 | Optional |
If your project is in Europe, impact testing is not optional—EN 10210 or EN 10025 compliance is mandatory for CE-marked structures.
Tolerance & Testing
- GB/T: More flexible; tolerances depend on grade; testing optional unless specified.
- EN: Tight tolerances; requires EN 10204 3.1 certificates, impact tests, weldability (Pcm) control.
- ASTM: Clear dimensional tolerances; destructive tests (flattening, flaring) required; impact testing optional.
See our blog on EN 10204 Certificates to understand documentation requirements.
How to Choose the Right Standard
- Check Project Location
- EU project → must use EN (with CE compliance).
- US project → typically requires ASTM.
- Asian OEM or non-EU machinery → GB/T is widely accepted.
- Consider Application Needs
- Balance Cost and Compliance
- GB/T often offers cost advantage + flexibility.
- EN/ASTM required for compliance in regulated projects.
YIGE Steel’s Advantage
At YIGE Steel, we bridge the gap between standards by offering:
- GB/T tubes (Q345, Q460, Q690) with flexible customization.
- EN-compliant tubes (S355J2H, S460J2H) with CE, ISO, and BV certifications.
- ASTM A500 equivalents for North American customers.
- Flexible MOQ: 1 ton for seamless, 25 tons for welded.
- Over 400 molds for cold drawn shaped tubes.
Explore our cold drawn seamless tubes to see how we combine precision, strength, and global compliance.
Conclusion
Choosing between GB/T, EN, and ASTM standards depends on project location, application, and compliance needs.
- Use EN for EU structural projects with CE marking.
- Use ASTM for North America and oil & gas projects.
- Use GB/T for flexible, cost-effective, and custom solutions.
At YIGE Steel, we provide global standard coverage, flexible MOQ, and CE-certified products—ensuring you don’t have to compromise between compliance and efficiency.
