1. LSAW stands for straight seam submerged arc welding and HSAW stands for spiral submerged arc welding. Both are used in the manufacture of steel pipes.
2. LSAW is formed by bending individual plates to form a U-shape and then welding the edges to form a longitudinal joint; HSAW is formed by wrapping steel strips to form a helix and then welding the edges to form a spiral joint.
3. Longitudinal submerged arc welded pipelines are suitable for transporting oil and gas, while spiral submerged arc pipelines are suitable for water transmission and structural applications, especially for large projects.
4. Tianjin Yuantai Derun Steel Pipe Manufacturing Group produces both LSAW and Spiral Submerged Arc Welded (SSAW) pipelines, which are widely used in international pipeline projects and are completed with low cost and high IRR.
5. LSAW pipes are made from plain sheet metal or thin plate and are longitudinally welded inside and out using the submerged arc welding process.
7. Longitudinal submerged arc welded pipes are suitable for diameters from 16" to 60", while spiral submerged arc welded pipes are suitable for diameters over 140".
8. It is recommended that resistance welding be used for the manufacture of pipes less than 16 inches in diameter.
9. LSAW pipe costs more than HSAW pipe, but its longitudinal welds have better strength and can be physically inspected using radiographic testing, ultrasonic testing, hydrostatic testing and cosmetic inspection for quality assurance.
10. HSAW pipes cost less than LSAW pipes, but the length of their spiral welds can result in lower strength than LSAW pipes. Long spiral welds can also lead to defects such as pipe cracks and uneven weld buildup.
11. HSAW, LSAW and ERW pipelines are suitable for different types of pipeline projects, please consult our account manager for details.