

1. Welded Steel Pipes for Low-Pressure Fluid Transmission (GB/T3092-1993) 2. Galvanized Welded Steel Pipes for Low-Pressure Fluid Transmission (GB/T3091-1993) 3. Steel Wire Housings for General Carbon Steel (GB3640-88) 4. Straight Seam Welded Steel Pipes (YB242-63) 5. Spiral Seam Submerged Arc Welded Steel Pipes for Pressure Fluid Transmission (SY5036-83) 6. Spiral Seam High-Frequency Welded Steel Pipes for Pressure Fluid Transmission (SY5038-83) 7. Spiral Seam Submerged Arc Welded Steel Pipes for General Low-Pressure Fluid Transmission (SY5037-83) 8. Spiral Seam High-Frequency Welded Steel Pipes for General Low-Pressure Fluid Transmission (SY5039-83) 9. Spiral Seam Welded Steel Pipes for Piling (SY5040-83)





