EN 10217-1 P235TR2 is a standard and widely used material specification for manufacturing Spiral Submerged Arc Welded (SSAW) steel pipes . This combination is a common product offered by numerous manufacturers for general pressure purposes and fluid transmission applications where medium strength and compliance with the Pressure Equipment Directive (PED) are required .
The designation "EN 10217-1 P235TR2 Spiral Submerged Arc Pipe" combines a medium-strength pressure pipe grade (P235TR2) with the enhanced TR2 quality level, produced using the spiral welding process for large-diameter, PED-compliant piping solutions .
📋 Key Specifications for EN 10217-1 P235TR2 SSAW Pipe
The table below summarizes the primary specifications for this product, based on comprehensive industry data .
| Attribute | Description |
|---|---|
| Standard | EN 10217-1: "Welded steel tubes for pressure purposes - Part 1: Non-alloy steel tubes with specified room temperature properties" . |
| Steel Grade | P235TR2: A medium-strength pressure purpose steel grade. "P" indicates pressure purpose, "235" indicates minimum yield strength in MPa, and "TR2" denotes Transportation Fluid Category 2 with specified aluminum content, mandatory impact properties, and specific inspection requirements . |
| Material Number | 1.0255 . |
| Manufacturing Process | Spiral Submerged Arc Welding (SSAW/HSAW/SAWH) : Formed from hot-rolled steel coil, with the weld seam running continuously in a spiral along the pipe's length. EN 10217-1 explicitly permits SAWH (helical seam) manufacturing routes 4a-9a for TR2 quality . |
| Chemical Composition (max %) | Carbon (C): 0.16% max Silicon (Si): 0.35% max Manganese (Mn): 1.20% max Phosphorus (P): 0.025% max Sulfur (S): 0.020% max Aluminum (Al tot): 0.02% min (key requirement for TR2) Cr+Cu+Mo+Ni: 0.70% max total residual elements |
| Mechanical Properties at Room Temperature | Yield Strength (t ≤ 16mm): 235 MPa minimum Yield Strength (16 < t ≤ 40mm): 225 MPa minimum Tensile Strength: 360-500 MPa Elongation (longitudinal): ≥ 25% Elongation (transverse): ≥ 23% |
| Impact Properties | Charpy V-notch Impact: 40 J minimum at 0°C (longitudinal) 28 J minimum at -10°C (longitudinal, Option 5) 27 J minimum at 0°C (transverse) |
| Temperature Range | Room temperature service (specified for ambient temperatures). For elevated temperature service, see EN 10217-2 (P235GH). |
| PED Compliance | TR2 quality is intended to support the essential requirements of EU Directive 2014/68/EU for pressure equipment with specified room temperature properties. For use in PED Categories II, III, and IV, TR2 grades with specific inspection are necessary . |
| Raw Material Requirement | Must be made from fully killed steel containing nitrogen-binding elements . |
| Typical Size Range | Outside Diameter: 10.2 mm to 2540 mm for EN 10217-1; SSAW typically 219 mm to 4064 mm (approx. 8" to 160") Wall Thickness: 0.5 mm to 40 mm (common range for SSAW: 4-25 mm) Length: 1.5 m to 18 m standard; up to 25 m available |
| Key Testing Requirements | Tensile Test: Per heat batch Impact Test: Mandatory Charpy V-notch at 0°C (40J longitudinal) Weld Bend Test: Mandatory for SAW tubes Hydrostatic Test: 100% of pipes; ≥ 1.5 × design pressure for ≥ 10 seconds NDT of Weld: 100% of weld length (ultrasonic or radiographic) Flattening Test: For D < 600mm and T/D ≤ 0.15 Chemical Analysis: Full verification of composition, including Al content |
| Common Applications | General pressure systems at ambient temperatures; industrial process water; compressed air lines; HVAC systems; fire protection systems; district heating; PED-compliant pressure equipment . |
| Certification | Mill Test Certificate to EN 10204 Type 3.1 with full test results, traceability records, and PED documentation . |
📊 TR2 vs. TR1 Quality Level Comparison
The table below highlights the critical differences between TR2 and TR1 quality levels for P235 grade :
| Feature | P235TR1 | P235TR2 | Significance for TR2 |
|---|---|---|---|
| Aluminum (Al) requirement | Not specified | ≥ 0.02% min | Grain refinement for enhanced toughness |
| Sulfur (S) max | 0.020% | 0.020% (same) | - |
| Raw Material | No special requirement | Fully killed steel required | Improved quality and uniformity |
| Impact Testing | Not required | Mandatory (40J @ 0°C longitudinal) | Guaranteed toughness for safety-critical applications |
| Manufacturing Routes for TR2 | All routes permitted | Routes 1a, 1b, 2a, 4a NOT permitted | Higher quality process control |
| PED Compliance | Does NOT support PED | Supports PED 2014/68/EU requirements | Suitable for CE-marked pressure equipment |
| Inspection Requirements | Non-specific | Specific inspection | Enhanced quality control and traceability |
| Testing Program | Basic | Comprehensive | Full mechanical and NDT validation |
🔍 Key Points to Understand
What "EN 10217-1 P235TR2" Means: This is the European standard for welded pressure pipes with room temperature properties. P235TR2 is a medium-strength grade, with minimum yield strength of 235 MPa. The "TR2" designation indicates enhanced quality level with specified aluminum content (≥0.02%), mandatory impact testing (40J at 0°C), and specific inspection requirements .
PED Compliance Significance: Tube grades in quality TR2 are intended to support the essential requirements of EU Directive 2014/68/EU for pressure equipment with specified room temperature properties. For use in pressure equipment in accordance with PED Categories II, III, and IV, TR2 grades with specific inspection are necessary .
P235TR2 vs. P235TR1: The key differences are :
Raw Material: TR2 requires fully killed steel; TR1 does not
Aluminum: TR2 requires minimum aluminum content (≥0.02%) for grain refinement
Impact Testing: TR2 requires mandatory Charpy impact testing at 0°C (40J minimum longitudinal)
Manufacturing Routes: TR1 is suitable for all manufacturing routes in EN 10217; manufacturing numbers 1a, 1b, 2a, and 4a cannot be used to manufacture TR2
PED Compliance: TR2 supports PED requirements; TR1 does not
Manufacturing Process Requirements: For TR2 quality, the manufacturing route must be carefully selected. Routes 1a, 1b, 2a, and 4a are not permitted for TR2 production. Acceptable routes include those with heat treatment or normalized conditions .
SSAW Advantages for P235TR2: The spiral welding process offers specific benefits for large-diameter, PED-compliant pipes :
Large Diameter Capability: Can economically produce pipes up to 160" diameter
PED Compliance: EN 10217-1 explicitly permits SAWH (helical submerged arc welding) for TR2 quality with appropriate manufacturing routes
Long Lengths: Up to 25m lengths reduce field joints
Cost Efficiency: Lower cost than LSAW for very large diameters
International Equivalents: P235TR2 has no direct equivalents in ASTM, ISO, or JIS standards, though it is approximately similar in strength to ASTM A53 Grade B .
🔧 Manufacturing Process for EN 10217-1 P235TR2 SSAW Pipe
The manufacturing process follows enhanced quality controls suitable for TR2 certification and PED compliance :
| Step | Description |
|---|---|
| 1. Raw Material Preparation | Hot-rolled steel coils meeting P235TR2 chemistry requirements (continuous cast, fully killed steel, fine grain practice with Al ≥ 0.02%) are leveled, inspected, and edge-milled . |
| 2. Spiral Forming | The steel strip is continuously formed into a cylindrical shape at a specific helix angle at room temperature. |
| 3. Submerged Arc Welding | Double-sided automatic submerged arc welding (inside and outside) creates the spiral seam with full penetration. Manufacturing routes 4a-9a per EN 10217-1 are applicable for TR2 quality . |
| 4. Non-Destructive Testing | 100% ultrasonic or radiographic inspection of the weld seam is mandatory for TR2 quality . |
| 5. Hydrostatic Testing | Each pipe individually tested to verify pressure integrity (≥ 1.5 × design pressure, ≥ 10 seconds) . |
| 6. Mechanical Testing | Tensile tests, weld bend tests, flattening tests, and mandatory Charpy impact testing at 0°C to verify properties . |
| 7. Dimensional Inspection | 100% verification of dimensions, straightness, and end squareness. |
| 8. End Finishing | Ends prepared (plain or beveled) for field welding; beveled ends for wall thickness > 4mm. |
| 9. Certification | EN 10204 Type 3.1 inspection certificate with full traceability, chemical analysis, mechanical properties, and PED documentation . |
🏭 Applications
EN 10217-1 P235TR2 SSAW pipes are used in general pressure applications where PED compliance is required :
| Application | Temperature Range | Why P235TR2 is Chosen |
|---|---|---|
| General Pressure Systems | Ambient | PED-compliant for pressure equipment; guaranteed impact properties |
| Industrial Process Water | Ambient | Good strength-to-cost ratio; PED certification |
| Compressed Air Systems | Ambient | Excellent weldability, certified quality |
| Fire Protection Systems | Ambient | Meets pressure requirements with full traceability |
| District Heating | Ambient (or low temp) | Cost-effective for large diameters; PED compliant |
| HVAC Systems | Ambient | Suitable for building services requiring certification |
| Pressure Equipment | Ambient | PED Categories II, III, IV with specific inspection |
📝 Important Considerations
PED Compliance: TR2 quality is intended to support the essential requirements of EU Directive 2014/68/EU for pressure equipment. For use in PED Categories II, III, and IV, TR2 grades with specific inspection are necessary .
Manufacturing Route Selection: For TR2 quality, you must ensure the manufacturer uses an approved manufacturing route. Routes 1a, 1b, 2a, and 4a are not permitted for TR2 production .
Aluminum Requirement: The minimum aluminum content of 0.02% is critical for grain refinement and achieving the required impact properties. This must be verified in the Mill Test Certificate .
Impact Testing: Mandatory Charpy V-notch testing at 0°C (40J longitudinal) ensures guaranteed toughness. Option 5 allows additional verification at -10°C (28J) .
Elevated Temperature Service: P235TR2 is specified for room temperature properties. For elevated temperature service (above ambient), consider EN 10217-2 P235GH instead .
Inspection Requirements: TR2 quality has specific inspection requirements, meaning more rigorous third-party inspection and testing compared to TR1 .
Weldability: P235TR2 has excellent weldability with low carbon equivalent. For PED-compliant applications, welding procedures should be qualified and documented.
Cost Premium: TR2 quality typically commands a premium over TR1 due to stricter chemistry controls (Al requirement), mandatory impact testing, and enhanced quality requirements.
Complete Specification: When ordering, specify :
EN 10217-1, Grade P235TR2, SAWH (spiral welded), Size (OD x WT), Length, End Finish
Standard version: [e.g., EN 10217-1:2019]
Coating requirements: [e.g., bare, varnish, FBE, 3LPE]
Manufacturing route: [if required by project]
Option 5: [if -10°C impact testing needed]
📝 Summary
EN 10217-1 P235TR2 Spiral Submerged Arc Welded pipes are a standard, PED-compliant choice for general pressure applications under the European pressure pipe standard . With minimum yield strength of 235 MPa – equivalent in strength to ASTM A53 Grade B – these pipes offer an excellent balance of strength and economy for industrial process water, compressed air, HVAC systems, and other pressure applications requiring CE marking and PED compliance .
The TR2 quality level provides essential enhancements over TR1 including fully killed steel requirement, specified aluminum content (≥0.02%), mandatory impact testing at 0°C (40J longitudinal), and strict manufacturing route requirements . These features make TR2 the minimum quality for applications requiring compliance with EU Directive 2014/68/EU for pressure equipment .
Available in diameters from 10.2mm to over 2500mm with wall thicknesses to 40mm and lengths up to 25m, these pipes are produced using the cost-effective SSAW manufacturing process while meeting the rigorous requirements of the EN 10217-1 specification for TR2 quality .
P235TR2 is the workhorse TR2 grade for general pressure applications, offering approximately 20% higher yield strength than P195TR2 . It is the default choice for PED-compliant pressure applications where guaranteed impact properties and enhanced quality control are required.
When ordering, ensure you clearly indicate the complete standard with grade, TR2 quality, manufacturing process (SAWH), required dimensions, and any coating requirements based on your specific application and PED requirements .
