The ministerial standard for spiral steel pipes is SY/T5037-2000 (Spiral submerged arc welded steel pipes for ordinary fluid transmission pipelines). This standard is a ministerial standard, and GB/T9711 is a national standard. The national standard has higher requirements for steel pipes than the ministerial standard.

Main production processes of ministerial spiral steel pipes

Uncoiling - Rolling up - Leveling - Butt welding - Milling - Forming - Internal welding - External welding - Pipe cutting - Breaking - Subsequent welding - Water pressure test

The main differences between ministerial spiral steel pipes and national spiral steel pipes

1. Purpose (5037 is a steel pipe for ordinary flow conveying pipelines; 9711 is a steel pipe for industrial conveying)

2. Detection method

3. Various performance indicators

4. Standard national standard steel pipes do not allow Q235B material and must be pipeline steel

Symbols mainly used for spiral steel pipes in ministerial standards

D - nominal outer diameter of steel pipe mm

T - nominal wall thickness of steel pipe mm

M - Mass of steel pipe line kg/m

P - Test pressure for hydrostatic test, Mpa

S - Test stress of hydrostatic test, Mpa

H - Weld reinforcement mm