EN S355 welded steel pipes, with a base material conforming to EN 10025-2 European standard low-alloy high-strength structural steel, are divided into two main standards: structural and pressure-bearing fluid. They encompass three mainstream welding processes:

ERW High-Frequency Straight Seam Welded Pipe (small to medium diameter, cold-formed EN 10219)

SSAW Spiral Submerged Arc Welded Pipe (ultra-large diameter long-distance pipelines)

LSAW Straight Seam Submerged Arc Welded Pipe (thick-walled, high-pressure, heavy-duty pile foundations)

Two Core Product Standards:

EN 10219: Cold-formed welded structural hollow pipe (factory columns, bridge casings, steel structure supports, not for high-pressure media)

EN 10217-5: Submerged arc welded steel pipes for pressure applications (water supply and drainage, medium-pressure gas, industrial circulating pressure pipelines, meeting EU PED pressure directive)

Product information：

Chemical composition (%)

Three Welding Process Parameters and Applicable Diameters

1. ERW High-Frequency Straight Seam Welded Pipe (EN10219)

Outer Diameter: 21.3~610mm (1/2"~24"), Wall Thickness: 1.5~16mm

Advantages: High dimensional accuracy, uniform wall thickness, fast delivery, lowest unit price

Applications: Steel structures in factories, low-pressure water supply and drainage, guardrails, small supports

2. SSAW Spiral Submerged Arc Welded Pipe (EN10217-5)

Outer Diameter: 219~3620mm, Wall Thickness: 6~40mm

Advantages: Can produce ultra-large diameters, multiple pipe diameters produced from the same steel strip, cost lower than large-diameter LSAW

Advantages and Characteristics: Oblique weld seam disperses soil stress, buried pipe resists uneven settlement, earthquake resistance

Applications: Urban main water supply, long-distance sewage, large bridge steel casing

3. LSAW Straight Seam Submerged Arc Welded Pipe

Outer Diameter: 406~1620mm, Wall Thickness: 10~60mm Thick-walled

Advantages: Short weld seam, low residual stress, high flaw detection pass rate; preferred for high-pressure and heavy-duty applications

Applications: Medium and high-pressure gas trunk lines, deep-sea casings, large wind power foundations, chemical process pipelines

Core Advantages

High Strength, Cost Savings

Under the same pressure conditions, thinner wall thickness can be selected compared to S235, reducing weight and overall procurement costs; deeply buried pipelines resist soil compression without deformation.

Preferred for Heavy-Duty Pile Foundations

Used in docks, bridges, deep foundation pit steel casings, and wind power foundation columns, it is not easily flattened or bent under high soil lateral pressure.

Spiral Welds Resist Settlement and Seismic Resistance

Diagonal welds disperse stress, making it less prone to cracking and leakage in long-distance high-pressure buried water and gas pipelines.

Universally Applicable to European Standards, Smooth Export Customs Clearance

Using the same standards for infrastructure bidding in the EU, Central Asia, and North Africa, with complete certifications, eliminating customs clearance risks due to non-compliance with standards.

Adaptable to Various Anti-corrosion Processing

Multi-layer external anti-corrosion can be applied, suitable for long-term underground laying in corrosive soil environments.