
Dimensional tolerance of erw steel pipe
ERW pipe means Electric Resistance Welded Pipe. ERW steel pipes and tubes are used. ERW steel pipes and tubes are used in various engineering purposes, fencing, scaffolding, line pipes etc.
Typical ERW Pipe Manufacturing Process
Our manufacturing process generally involves the following stages in a step by step procedure.
ERW Pipe Manufacturing process
HR Coils are slitted to pre-determined widths for each and every size of pipes
Uncoiling, End Shearing And Welding
The slitted coil is uncoiled at the entry of ERW mill and the ends are sheared and welded one after another. This results in a single endless strip.
Forming
The slitted coils are initially formed into U shape and after that into a cylindrical shape with open edges utilizing a series of forming rolls.
Tolerance of outside diameter
Standard | Out Diameter | Tolerance of Pipe End | Tolerance of Pipe Body |
API 5L | 219.1-273.1 | +1.6mm, -0.4mm | ±0.75% |
274.0-320 | +2.4mm, -0.8mm | ±0.75% | |
323.9-457 | +2.4mm, -0.8mm | ±0.75% | |
508 | +2.4mm, -0.8mm | ±0.75% | |
559-610 | +2.4mm, -0.8mm | ±0.75% |
Tolerance of wall thickness
Standard | Grade | Out Diameter | Wall Thickness |
API 5L | / | 219.1-457 | +15%, -12.5% |
B | 508-610 | +17.5%, -12.5% | |
X42-X80 | 508-610 | +19.5%, -8% |