ERW / HFW Pipe: Electric Resistance Welded & High-Frequency Welded Steel Pipe
Grade- ASTM A500B, A53B, API5L GRB – X70 OD-2-3/8″ – 26” WT-0.188″ – 0.844″
Double Submerged Arc Welded (DSAW) pipe is a high-strength steel pipe manufactured using a specialized welding process that ensures superior durability and reliability for demanding applications. It is produced by forming a single piece of steel plate into a cylindrical shape through rolling or pressing, followed by welding the longitudinal seam on both the inside and outside surfaces using submerged arc welding. This “double” welding technique—where the arc is protected by a layer of flux—creates a robust, fully penetrated weld that minimizes impurities and enhances structural integrity. DSAW pipes are available in straight-seam or spiral-seam configurations, with spiral variants (also known as HSAW) featuring a helical weld for longer lengths up to 155 feet.
Key Features and Benefits
- Fast & Cost-Effective Production: Continuous roll-forming and in-line welding enable high-speed manufacturing and lower cost compared to seamless or DSAW pipes.
- Excellent Dimensional Accuracy: Tight tolerances on diameter, wall thickness, and ovality; typically produced from 1/2″ NPS up to 26″ OD (most common 2″–24″).
- Strong, Clean Weld Seam: High-frequency process removes most of the heat-affected zone, producing a weld as strong as the parent metal with minimal internal/external bead (often scarfed flush).
- Wide Grade Range: Available in carbon steel grades (API 5L Gr.B, X42–X80, ASTM A53 Gr.A/B, A500, etc.) and some stainless grades.
- Superior Surface Finish: Smooth inside and outside surfaces make it ideal for flow applications and easy coating (galvanizing, FBE, 3LPE, etc.).
Common Applications
- Oil and gas gathering lines, flow lines, and transmission pipelines (especially sour service with HFW).
- Water and utility distribution lines.
- Structural tubing (columns, scaffolding, fencing).
- Mechanical tubing in automotive, furniture, and conveyor systems.
- Fire sprinkler and HVAC systems.
- Low- to medium-pressure pipelines where seamless pipe is not required.
Why Choose ERW/HFW?
ERW/HFW pipe delivers the perfect balance of performance, availability, and economy for diameters up to 26 inches. With modern HFW technology, today’s ERW pipe meets or exceeds the most stringent API 5L, ASTM, and EN standards, making it the go-to choice for the majority of line pipe and structural projects worldwide.
