EN S355JRH steel is a standard and widely available material grade for manufacturing Longitudinal Submerged Arc Welded (LSAW) pipes. It is a high-strength structural steel commonly specified for construction, engineering, and piling applications. The finished pipe is typically manufactured to the EN 10219 product standard for structural hollow sections, where it is designated as S355JRH [citation:1, citation:3, citation:7].
The steel plate used as raw material is specified under EN 10025-2, while the finished pipe product conforms to EN 10219 [citation:3, citation:7].
Here is the detailed specification for an EN S355JRH LSAW pipe.
Key Specifications
| Attribute | Description |
|---|---|
| Material Standard | EN 10025-2: Hot-rolled products of structural steels. This standard specifies the technical delivery conditions for the steel plate [citation:3, citation:7]. |
| Steel Grade | S355JRH: A high-strength non-alloy structural steel grade. The "355" indicates the minimum yield strength in MPa. The suffix "JR" denotes a specified minimum impact energy of 27 Joules at room temperature (+20°C) . The "H" indicates it is a hollow section [citation:3, citation:7]. |
| Product Standard | EN 10219-1/-2: Cold-formed welded structural hollow sections of non-alloy and fine grain steels. This is the most common standard for the finished LSAW pipe product [citation:1, citation:3, citation:4, citation:7, citation:8]. |
| Process | LSAW (Longitudinal Submerged Arc Welding) : Pipes are manufactured by forming steel plates into a cylinder (using UOE, JCOE, or RBE technology) and welding the longitudinal seam both internally and externally using a submerged arc process [citation:2, citation:5, citation:9]. |
| Chemical Composition (max %) [citation:3, citation:7] | |
| Carbon (C): 0.22 | |
| Manganese (Mn): 1.60 | |
| Phosphorus (P): 0.035 | |
| Sulfur (S): 0.035 | |
| Silicon (Si): 0.55 | |
| Nitrogen (N): 0.009 | |
| Mechanical Properties (min) [citation:3, citation:7] | |
| Yield Strength: 355 MPa (for thickness ≤ 16mm) | |
| Tensile Strength: 510-680 MPa | |
| Elongation: 20% | |
| Impact Properties [citation:3, citation:7] | Charpy V-notch Impact Energy: 27 J minimum at +20°C |
| Typical Size Range [citation:1, citation:3, citation:7, citation:8] | |
| Outside Diameter: 219 mm to 1820 mm (8" to 72") | |
| Wall Thickness: 5.0 mm to 50 mm | |
| Length: 3 m to 18 m (up to 75 m available for specific applications like piling) [citation:2, citation:9] | |
| Manufacturing Steps [citation:2, citation:9] | 1. Steel plate selection and edge milling. 2. Edge crimping. 3. Forming using JCOE or UOE processes. 4. Internal and external submerged arc welding. 5. Mechanical expanding (for UOE/JCOE). 6. Non-destructive testing (Ultrasonic, X-ray). 7. Hydrostatic testing. 8. End facing and beveling. |
| Common Applications [citation:2, citation:3, citation:7, citation:8] | High-rise building support columns; steel structure frames; bridge main beams; wind power towers; solar power brackets; port and wharf construction; piling foundations; mechanical equipment brackets; offshore projects. |
| Certification | Mill Test Certificate typically to EN 10204 / 3.1 [citation:1, citation:2, citation:5, citation:8]. |
Understanding the Grade Designation
The complete designation S355JRH can be broken down as follows [citation:3, citation:7]:
| Component | Meaning |
|---|---|
| S | Structural Steel |
| 355 | Minimum yield strength of 355 MPa (for thickness ≤ 16mm) |
| JR | Impact test requirement: 27 Joules minimum at room temperature (+20°C) |
| H | Hollow Section (conforms to EN 10219) |
Advantages of EN S355JRH LSAW Pipe
| Advantage | Description |
|---|---|
| High Strength | Minimum yield strength of 355 MPa – significantly higher than S275 grades, allowing for thinner walls or higher load capacity [citation:3, citation:7]. |
| Good Weldability | Controlled chemistry ensures excellent weldability for field joining and fabrication [citation:3, citation:7]. |
| Guaranteed Toughness | The "JR" suffix guarantees minimum impact energy of 27 Joules at room temperature, ensuring adequate toughness for general structural applications [citation:3, citation:7]. |
| Large Diameter Capability | LSAW process enables production of large-diameter pipes (up to 72"+) ideal for major construction and infrastructure projects [citation:1, citation:2, citation:8]. |
| Thick Walls | Available with wall thicknesses up to 50-60 mm, providing high load-bearing capacity for demanding applications like piling [citation:2, citation:3, citation:9]. |
| Dimensional Accuracy | Modern JCOE and UOE forming processes provide precise control over pipe dimensions [citation:2, citation:5]. |
| Excellent Bending Strength | The combination of high strength and good ductility makes it ideal for heavy-load, high-reliability scenarios [citation:3, citation:7]. |
Summary
In conclusion, EN S355JRH LSAW pipe is a well-established, high-strength structural steel pipe manufactured to the EN 10219 product standard. It combines a minimum yield strength of 355 MPa with guaranteed room-temperature impact toughness (27J at +20°C), making it suitable for a wide range of demanding applications in building construction, bridge engineering, energy projects, and piling foundations [citation:2, citation:3, citation:7, citation:8]. The LSAW manufacturing process enables production of large diameters (up to 72"+) with thick walls (up to 50-60 mm), providing excellent load-bearing capacity for major infrastructure projects. When specifying, reference both the material grade and the product standard (e.g., EN 10219 S355JRH LSAW pipe) to ensure the pipe meets all requirements for its intended use.
