BS EN 10219-1 Spiral Welded Steel Pipe (SSAW)
Basic Overview
BS EN 10219-1 is the European standard for cold-formed welded structural hollow sections made from non-alloy and fine grain steels . This standard explicitly covers spiral submerged arc welded (SSAW/SAWH) pipes used for structural applications in construction, bridges, buildings, and engineering projects .
Unlike pressure pipe standards (EN 10217 series), EN 10219-1 is specifically designed for load-bearing structural applications where the pipe serves as a column, beam, truss member, or foundation pile .
Name Explanation
| Part | Meaning |
|---|---|
| BS EN | British Standard adopted from European Norm |
| 10219-1 | Cold formed welded structural hollow sections - Part 1: Technical delivery conditions |
| SSAW | Spiral Submerged Arc Welding – pipe formed from steel coil with continuous spiral seam; also known as SAWH (helical seam) |
| Cold-formed | Formed at room temperature without subsequent heat treatment (except weld seam normalization) |
Key Specifications
| Attribute | Description |
|---|---|
| Standard | BS EN 10219-1:2006 (current) |
| Product Type | Cold-formed welded structural hollow sections |
| Shapes | Circular, square, rectangular, and special shapes |
| Manufacturing Processes | Spiral Submerged Arc Welding (SSAW/SAWH) , Longitudinal Submerged Arc Welding (LSAW), Electric Resistance Welding (ERW) |
| Primary Application | Structural engineering, building construction, bridges, piling foundations, mechanical engineering |
| Steel Grades | S235JRH, S275J0H, S275J2H, S355J0H, S355J2H, S355K2H, plus fine grain grades (S275NH, S355NH, S460NH, etc.) |
| Size Range (SSAW) | 219 mm to 4064 mm (8" to 160") OD |
| Wall Thickness | 4 mm to 40 mm (common range 5-25.4 mm) |
| Length | 6 m to 18 m standard; up to 32 m available |
Steel Grades: Designation System
The grade designation follows a logical structure :
| Component | Meaning |
|---|---|
| S | Structural Steel |
| 235/275/355 | Minimum yield strength in MPa (for thickness ≤ 16mm) |
| JR / J0 / J2 / K2 | Impact test temperature and energy |
| H | Hollow Section (conforms to EN 10219) |
Impact Suffixes
| Suffix | Impact Test Temperature | Minimum Impact Energy |
|---|---|---|
| JR | +20°C (room temperature) | 27 J |
| J0 | 0°C | 27 J |
| J2 | -20°C | 27 J |
| K2 | -20°C | 40 J |
Chemical Composition (max %)
| Grade | C | Si | Mn | P | S |
|---|---|---|---|---|---|
| S235JRH | 0.17 | - | 1.40 | 0.040 | 0.040 |
| S275J0H | 0.20 | - | 1.50 | 0.035 | 0.035 |
| S275J2H | 0.20 | - | 1.50 | 0.030 | 0.030 |
| S355J0H | 0.22 | 0.55 | 1.60 | 0.035 | 0.035 |
| S355J2H | 0.22 | 0.55 | 1.60 | 0.030 | 0.030 |
| S355K2H | 0.22 | 0.55 | 1.60 | 0.030 | 0.030 |
*Note: Fully killed steel (FF) containing nitrogen-binding elements (e.g., min. 0.020% total Al) is required .*
Mechanical Properties (min)
| Grade | Yield Strength (t ≤ 16mm) | Tensile Strength | Elongation | Impact (℃) |
|---|---|---|---|---|
| S235JRH | 235 MPa | 360-510 MPa | 24% | 27J at +20℃ |
| S275J0H | 275 MPa | 410-560 MPa | 20% | 27J at 0℃ |
| S275J2H | 275 MPa | 410-560 MPa | 20% | 27J at -20℃ |
| S355J0H | 355 MPa | 470-630 MPa | 20% | 27J at 0℃ |
| S355J2H | 355 MPa | 470-630 MPa | 20% | 27J at -20℃ |
| S355K2H | 355 MPa | 470-630 MPa | 20% | 40J at -20℃ |
Note: For thickness > 16mm, yield strength decreases (e.g., S355J2H: 345 MPa for 16<t≤40mm) .
SSAW Manufacturing Process
Spiral welded pipes under EN 10219-1 are produced using the following process :
| Step | Description |
|---|---|
| 1. Coil Preparation | Hot-rolled steel coils meeting EN 10219-1 chemistry requirements |
| 2. Uncoiling/Leveling | Steel coil is uncoiled and leveled |
| 3. Edge Milling | Strip edges are milled for proper welding |
| 4. Spiral Forming | Steel strip is continuously formed into a cylindrical shape at a specific helix angle at room temperature (cold-formed) |
| 5. Submerged Arc Welding | Double-sided automatic submerged arc welding (inside and outside) creates the spiral seam |
| 6. Weld NDT | 100% non-destructive testing (ultrasonic or eddy current) of weld seam |
| 7. Hydrostatic Testing | Optional – not mandatory for structural applications |
| 8. Finishing | End processing, coating, and marking |
Cold-Formed Definition: EN 10219-1 covers hollow sections produced by cold forming without subsequent heat treatment (except weld line heat treatment) .
Dimensional Tolerances (EN 10219-2)
| Parameter | Tolerance |
|---|---|
| Outside Diameter (D ≤ 168.3mm) | ±1% or ±0.5mm (whichever is greater) |
| Outside Diameter (D > 168.3mm) | ±1% |
| Wall Thickness (t ≤ 5mm) | ±10% |
| Wall Thickness (t > 5mm) | ±0.5mm |
| Straightness | ≤ 0.15% of total length (max 3mm/m) |
| Length (fixed) | +50mm / -0mm |
Typical Size Availability (SSAW):
| OD (inch) | OD (mm) | Wall Thickness Range (mm) |
|---|---|---|
| 16" | 406 | 5.0 - 16.0 |
| 20" | 508 | 5.0 - 18.0 |
| 24" | 610 | 5.0 - 20.0 |
| 30" | 762 | 6.0 - 22.0 |
| 36" | 914 | 6.0 - 25.0 |
| 40" | 1016 | 6.0 - 28.0 |
| 48" | 1219 | 8.0 - 30.0 |
| 56" | 1422 | 8.0 - 32.0 |
| 60" | 1524 | 8.0 - 32.0 |
| 64" | 1626 | 8.0 - 35.0 |
| 72" | 1829 | 8.0 - 35.0 |
Testing & Inspection Requirements
| Test Type | Requirement | Notes |
|---|---|---|
| Chemical Analysis | Per heat lot | Verifies composition limits per EN 10219-1 |
| Tensile Test | Per lot | Verifies yield and tensile strength |
| Flattening Test | Required | Checks ductility and weld integrity |
| Bend Test | Required | Verifies weld integrity |
| Charpy Impact Test | Mandatory for J0/J2/K2 grades | At specified temperature (0°C, -20°C) |
| Hydrostatic Test | Optional | Not mandatory for structural applications |
| Non-Destructive Testing (NDT) | 100% of weld seam | Ultrasonic or eddy current inspection |
| Dimensional Inspection | 100% | Per EN 10219-2 tolerances |
| Mill Test Certificate | EN 10204 Type 3.1B | Provided with full test results |
EN 10219-1 vs. EN 10217 Comparison
| Aspect | EN 10219-1 | EN 10217 |
|---|---|---|
| Application | Structural hollow sections | Pressure purposes |
| Hydrostatic Test | Not required | Required |
| Impact Testing | Mandatory for J0/J2/K2 grades | Required for GH grades |
| Typical Use | Buildings, bridges, piling, mechanical engineering | Boilers, pressure vessels, steam lines |
| Grade Suffix | H (Hollow section) | GH (Gases, High temperature) |
| SSAW Applicability | Explicitly covered | Covered (Part 5 specifically for SAW) |
Common Applications
| Application | Description |
|---|---|
| Building Construction | Columns, beams, trusses for high-rise buildings, stadiums, exhibition halls |
| Bridge Engineering | Structural members, supports, pedestrian bridges |
| Piling Foundations | Load-bearing piles for buildings and structures |
| Mechanical Engineering | Agricultural machinery, truck and trailer construction, cranes |
| Offshore Projects | Marine structures, port facilities |
| Infrastructure Projects | Tunnel supports, retaining walls, highway structures |
| Renewable Energy | Wind turbine towers, solar structures |
| Construction | Scaffolding, handrails, fencing |
Advantages of SSAW for EN 10219-1
| Advantage | Description |
|---|---|
| Large Diameter Capability | SSAW produces pipes from 8" to 160" OD – ideal for large-diameter structural applications |
| Cost-Effective | More economical than LSAW or seamless for large diameters |
| Long Lengths | Up to 32 m lengths reduce field splicing requirements |
| High Weld Integrity | Double-sided welding creates a single high-quality weld nugget |
| 100% NDT | Mandatory ultrasonic inspection of weld seam ensures quality |
| Cold-Formed | Tight dimensional tolerances and good surface finish |
| CE/UKCA Marking | Available for construction products under EU/UK regulations |
| Spiral Stress Distribution | Spiral weld disperses stress more evenly than straight seam |
Coating Options
EN 10219-1 SSAW pipes can be supplied with various coatings for corrosion protection:
| Coating Type | Best For | Key Features |
|---|---|---|
| 3LPE (3-layer polyethylene) | Buried pipelines | Excellent corrosion protection, high impact resistance |
| FBE (Fusion Bonded Epoxy) | Oil & gas pipelines | Strong adhesion, chemical resistance |
| Coal Tar Epoxy | Marine environments | Heavy-duty protection |
| Varnish / Anti-rust oil | Temporary protection | Short-term corrosion protection during transport |
| Bitumen Coating | Buried service | Cost-effective protection |
| Hot-dip Galvanized | Outdoor applications | Corrosion protection |
Important Considerations
1. EN 10219-1 vs. EN 10210
EN 10219-1: Cold-formed hollow sections (no heat treatment after forming)
EN 10210: Hot-finished hollow sections (formed at elevated temperatures)
For SSAW pipes, EN 10219-1 is the correct standard as SSAW is a cold-forming process
2. Grade Selection by Impact Temperature
S235JRH / S275JRH / S355JRH: 27 J at +20°C – indoor or warm climate applications
S275J0H / S355J0H: 27 J at 0°C – temperate climate outdoor structures
S275J2H / S355J2H: 27 J at -20°C – cold climates, demanding applications
S355K2H: 40 J at -20°C – critical applications requiring higher toughness
3. Product Standard vs. Material Standard
EN 10219-1 is the product standard (defines pipe geometry, tolerances, weld quality)
The material (steel plate) conforms to EN 10025-2
Complete specification requires both standards
4. SSAW Size Limitations
SSAW manufacturing for EN 10219-1 is typically available from 8" to 160" OD
Smaller diameters (under 8") are typically produced by ERW methods
5. Deoxidation Requirement
Fully killed steel (FF) is required, containing nitrogen-binding elements (e.g., min. 0.020% total Al)
6. Third-Party Inspection
Available inspection services include SGS, BV, Lloyds
Mill Test Certificate to EN 10204 Type 3.1B typically provided
Summary
BS EN 10219-1 Spiral Submerged Arc Welded (SSAW) steel pipe is the European standard for large-diameter cold-formed structural hollow sections used in construction, bridge engineering, piling foundations, and mechanical applications. The standard covers circular, square, and rectangular sections with steel grades from S235JRH to S355K2H, offering guaranteed impact toughness from room temperature down to -20°C (40J for K2).
Key features:
Product standard: EN 10219-1 – Cold-formed welded structural hollow sections
Material: Non-alloy and fine grain steels (fully killed, Al ≥ 0.020%)
Grades: S235JRH, S275J0H, S275J2H, S355J0H, S355J2H, S355K2H, plus fine grain grades
SSAW manufacturing produces pipes from 8" to 160" OD with wall thickness up to 40 mm
Double-sided welding creates a single high-quality weld nugget
100% NDT of weld seam ensures quality
Mandatory impact testing for J0/J2/K2 grades
Cold-formed – tight dimensional tolerances and good surface finish
CE/UKCA marking available for construction products
Common applications include:
Building construction (columns, beams, trusses)
Bridge engineering and infrastructure projects
Piling foundations
Offshore platforms and marine structures
Mechanical engineering and renewable energy
Scaffolding, handrails, fencing
When ordering, specify: BS EN 10219-1, Grade (e.g., S355J2H), SSAW (spiral submerged arc welded), Size (OD x WT), Length, End Finish (plain/beveled), Coating Requirements, and Mill Test Certificate to EN 10204 Type 3.1B. For structural applications in cold climates, specify J2 or K2 grades for guaranteed low-temperature toughness .
