BS EN 10219-2 Spiral Welded Steel Pipe (SSAW)
Basic Overview
BS EN 10219-2 is the European standard that specifies tolerances, dimensions, and sectional properties for cold-formed welded structural hollow sections. This standard works hand-in-hand with BS EN 10219-1 (which defines technical delivery conditions) to provide a complete specification for structural hollow sections including spiral submerged arc welded (SSAW/SAWH) pipes .
In simple terms: Part 1 tells you what the pipe is made of; Part 2 tells you how precisely it is made.
Key Specifications
| Attribute | Description |
|---|---|
| Standard | BS EN 10219-2:2019 – "Cold formed welded steel structural hollow sections - Tolerances, dimensions and sectional properties" |
| Part 1 Relationship | Works with EN 10219-1 (technical delivery conditions defining material grades and mechanical properties) |
| Scope | Specifies tolerances, dimensions, and sectional properties for cold-formed welded structural hollow sections of circular, square, rectangular, or elliptical forms |
| Manufacturing Process | Spiral (Helical) Submerged Arc Welding (SSAW/HSAW) is explicitly permitted, along with electric welded methods. Pipes are cold-formed without subsequent heat treatment (except weld line heat treatment) |
| Size Range | Outside Diameter: 21.3 mm to 3048 mm (approx. 0.8" to 120"); Wall Thickness: 1.0 mm to 40 mm standard; Length: 3 m to 32 m |
| Certification | Mill Test Certificate typically to EN 10204 Type 3.1 or 3.2 |
Tolerances and Dimensional Properties (Circular Sections)
EN 10219-2 specifies precise tolerances for structural hollow sections :
| Parameter | Tolerance Specification |
|---|---|
| Outside Diameter (≤ 40mm) | ±0.5 mm |
| Outside Diameter (40mm < D ≤ 168.3mm) | ±0.75% of D |
| Outside Diameter (> 168.3mm) | ±0.75% of D or as agreed |
| Wall Thickness (t ≤ 5mm) | ±10% of nominal |
| Wall Thickness (t > 5mm) | ±7.5% of nominal |
| Straightness | ≤ 0.15% of total length |
| Length (fixed lengths) | +50mm / -0mm |
Material Grades (Defined in Part 1)
The steel grades available for EN 10219-2 SSAW pipes include :
| Grade | Yield Strength (min) | Impact Test Temperature |
|---|---|---|
| S235JRH | 235 MPa | 27 J at +20°C |
| S275J0H | 275 MPa | 27 J at 0°C |
| S275J2H | 275 MPa | 27 J at -20°C |
| S355J0H | 355 MPa | 27 J at 0°C |
| S355J2H | 355 MPa | 27 J at -20°C |
| S355K2H | 355 MPa | 40 J at -20°C |
| S460NH / S460NLH | 460 MPa | Fine-grain steels for higher strength |
Impact Test Suffixes Explained
| Suffix | Impact Test Temperature | Minimum Impact Energy | Best For |
|---|---|---|---|
| JR | +20°C (room temperature) | 27 J | Indoor or warm climate applications |
| J0 | 0°C | 27 J | Temperate climate outdoor structures |
| J2 | -20°C | 27 J | Cold climates, demanding applications |
| K2 | -20°C | 40 J | Critical applications requiring higher toughness |
SSAW Manufacturing Process for EN 10219-2
Spiral welded pipes are produced using the following process :
| Step | Description |
|---|---|
| 1. Raw Material Preparation | Hot-rolled steel coils meeting EN 10219-1 chemistry requirements are leveled and inspected |
| 2. Edge Milling | Precision edge milling creates optimal bevel geometry for complete weld penetration |
| 3. Cold Forming | The coil is continuously spiral-formed into a cylindrical shape at ambient temperature (cold-formed) |
| 4. Submerged Arc Welding | Double-sided automatic SAW (inside and outside) creates the spiral seam with full penetration |
| 5. Weld Line Heat Treatment | Weld line may be heat-treated to ensure properties match base metal |
| 6. Sizing and Straightening | Pipe passes through sizing rolls to achieve final dimensions per EN 10219-2 tolerances |
| 7. Quality Inspection | Non-destructive testing (ultrasonic, X-ray); dimensional verification against Part 2 tolerances |
| 8. Mechanical Testing | Tensile tests, flattening tests, and Charpy impact tests verify properties per Part 1 requirements |
| 9. End Finishing | Ends prepared (plain or beveled) as required |
Testing & Inspection Requirements
| Test Type | Purpose | Notes |
|---|---|---|
| Chemical Analysis | Verify composition | Per heat lot |
| Tensile Test | Verify yield and tensile strength | Per lot |
| Flattening Test | Check ductility | Required |
| Bend Test | Verify weld integrity | Required |
| Charpy Impact Test | Verify low-temperature toughness | Mandatory for J0/J2/K2 grades at specified temperature |
| Non-Destructive Testing (NDT) | Weld seam inspection | 100% ultrasonic or eddy current |
| Dimensional Inspection | Verify tolerances | 100% per EN 10219-2 |
| Mill Test Certificate | Full traceability | EN 10204 Type 3.1 or 3.2 |
Applications and Grade Selection
BS EN 10219-2 SSAW pipes are widely used in structural applications where guaranteed dimensions and properties are critical :
| Application | Recommended Grades | Key Requirements |
|---|---|---|
| High-Rise Buildings | S355J2H, S355K2H | High strength, guaranteed -20°C impact toughness |
| Bridge Construction | S355J2H, S460NH | Fatigue resistance, low-temperature performance |
| Infrastructure Projects | S275J2H, S355J0H | Good weldability, cost-effective |
| Piling Foundations | S275J2H, S355J2H | Axial load capacity, driving resistance |
| Offshore Structures | S355K2H, S460NH | High strength, corrosion resistance |
| Wind Turbine Towers | S355J2H, S460NLH | Large diameters, high strength |
| Mechanical Frameworks | S235JRH, S275J0H | General structural use, economy |
Real-world project example: A 2022 Singapore subway project used 3,177 tons of EN 10219-1 S355JR spiral welded pipes for station construction .
EN 10219-2 vs. EN 10210 (Hot-Finished)
| Aspect | EN 10219-2 (Cold-Formed) | EN 10210 (Hot-Finished) |
|---|---|---|
| Manufacturing | Cold-formed at ambient temperature | Hot-finished at elevated temperatures |
| Surface Finish | Smoother surface finish | Mill scale present |
| Dimensional Tolerances | Tighter tolerances | Looser tolerances |
| Residual Stress | Higher residual stresses | Lower residual stresses |
| Typical Application | General structural, buildings | Heavy structural, bridges |
| Grades | S235JRH through S460NH | S235JRH through S460NH (similar) |
Coating Options
EN 10219-2 SSAW pipes can be supplied with various coatings for corrosion protection :
| Coating Type | Best For |
|---|---|
| Fusion Bond Epoxy (FBE) | Buried pipelines, corrosion protection |
| 3-layer polyethylene (3PE) | Buried pipelines, harsh environments |
| Hot-dip galvanizing | Outdoor exposed applications |
| Black oil / varnish | Temporary protection during transport |
Important Considerations
1. Complete Specification Required
When ordering, specify both parts of the standard:
EN 10219-1 Grade [e.g., S355J2H] (material)
EN 10219-2 (tolerances and dimensions)
SSAW (spiral welded) (manufacturing process)
Size (OD x WT), Length, End Finish
2. Cold-Formed vs. Hot-Finished
EN 10219 (cold-formed) differs from EN 10210 (hot-finished) in several ways:
EN 10219: Cold-formed without subsequent heat treatment (except weld line), tighter tolerances, smoother surface finish
EN 10210: Hot-finished, more relaxed tolerances, mill scale present
For SSAW pipes, EN 10219 is the correct standard as SSAW is a cold-forming process
3. Impact Testing Requirements
The grade suffix indicates impact test temperature :
JR: 27 J at +20°C
J0: 27 J at 0°C
J2: 27 J at -20°C
K2: 40 J at -20°C
4. CE Marking
Part 1 products can be CE marked under the Construction Products Regulation (CPR) .
5. High-Strength Grades
Part 2 covers higher-strength fine-grain steels like S460NH and S460NLH, which may require normalized plate and LSAW welding for thicker sections .
Summary
BS EN 10219-2:2019 is the European standard specifying tolerances, dimensions, and sectional properties for cold-formed welded structural hollow sections, including Spiral Submerged Arc Welded (SSAW) pipes . It works together with BS EN 10219-1, which defines material grades (S235JRH through S460NH) and mechanical properties .
These pipes combine the dimensional precision of cold-forming with the robust weld quality of the submerged arc process, making them ideal for demanding structural applications including buildings, bridges, infrastructure projects, piling foundations, and offshore structures . The standard permits pipe diameters up to 3048mm with wall thicknesses to 40mm, offering excellent design flexibility .
When ordering, specify: EN 10219-1 Grade [e.g., S355J2H] and EN 10219-2, SSAW (spiral welded), Size (OD x WT), Length, End Finish, and Mill Test Certificate to EN 10204 Type 3.1 .
