The welding processes primarily include three types:
high-frequency resistance welding (ERW), longitudinal submerged arc welding (LSAW), and spiral submerged arc welding (SSAW), which meet the requirements for pipe diameter, wall thickness, and pressure ratings under various operating conditions.
1.ERW Pipe (Electric Resistance Welded)
| Item | Specification |
| Outer Diameter Range | 9.5mm ~ 610mm |
| Wall Thickness Range | 1.5mm ~ 22mm |
| Length Range | 6m ~ 18m (customizable) |
| Manufacturing Process | Steel strip slitting → Forming → High-frequency resistance welding → Weld treatment → Sizing → Straightening |
| Features | High production efficiency (3× faster than SSAW), high diameter accuracy (tolerance ±0.5mm), smooth and uniform weld seam |
| Applicable Standards | ASTM A53, ASTM A135, GB/T 3091, BS 1387, JIS G3444, EN 10255 |
| Typical Applications | Low-pressure fluid transport, building structures, fire protection piping, water supply & drainage, general piping |
ERW pipe wall thickness tolerance is ±10% (e.g., 6mm wall thickness: 5.4-6.6mm is acceptable). Tensile strength must be ≥375MPa. The standard divides welded pipes into Grade L (ordinary) and Grade Q (reinforced), with Grade Q offering approximately 20% higher pressure capacity.
2. LSAW Pipe (Longitudinal Submerged Arc Welded)
| Item | Specification |
| Outer Diameter Range | 219mm ~ 1820mm |
| Wall Thickness Range | 3.2mm ~ 40mm |
| Length Range | 6m ~ 18m (customizable) |
| Manufacturing Process | Steel plate edge milling → Pre-bending → Forming (JCOE/UOE) → Internal & external submerged arc welding → Expanding → Inspection |
| Features | High weld quality, 100% ultrasonic + radiographic inspection capability, suitable for high-pressure large-diameter transport |
| Applicable Standards | API 5L, ASTM A672, ASTM A691, GB/T 9711, EN 10217 |
| Typical Applications | Oil & gas long-distance pipelines, high-pressure boiler piping, large structural supports |
3. SSAW Pipe (Spiral Submerged Arc Welded)
| Item | Specification |
| Outer Diameter Range | 219mm ~ 2540mm |
| Wall Thickness Range | 5.0mm ~ 50mm |
| Length Range | 6m ~ 18m (customizable) |
| Manufacturing Process | Steel coil uncoiling → Butt welding → Forming (spiral rolling) → Internal & external submerged arc welding → Pipe end treatment |
| Features | Large-diameter pipes can be produced from narrow strip steel, low cost, but longer weld seam and slightly lower precision than LSAW |
| Applicable Standards | API 5L, SY/T 5037, GB/T 9711, EN 10217 |
| Typical Applications | Low-pressure fluid transport, pile foundation pipes, dredging pipelines, large water conveyance projects |
Product Advantages
💰 High Cost Performance
Carbon steel welded pipe production cost is significantly lower than stainless steel pipe and seamless steel pipe, making it the economical choice for large-scale engineering projects.
⚡ High Production Efficiency
ERW pipe production speed is 3× faster than spiral welded pipe, suitable for rapid delivery of large-volume orders.
📐 Wide Specification Coverage
Outer diameter range 9.5mm~2540mm, wall thickness 1.5mm~50mm, covering almost all industrial application scenarios.
🔧 Excellent Processing Performance
Carbon steel has good weldability and machinability, especially low/medium carbon grades (A106 Gr.B, A53 Gr.B) which are easy to cut, bend, and weld.
🛡️ Multiple Anti-Corrosion Options Available
Hot-dip galvanizing: Zinc coating ≥80g/㎡, suitable for outdoor atmospheric environments
3PE/3LPP anti-corrosion: Three-layer polyethylene/polypropylene, suitable for buried long-distance pipelines
FBE epoxy powder: Fusion-bonded epoxy coating, suitable for high anti-corrosion requirements
Internal/external plastic coating: Epoxy resin lining, suitable for drinking water and chemical fluid transport
Asphalt/coal tar: Traditional anti-corrosion, low cost