What are the weld requirements for straight seam steel pipes?
1. The height of the weld burr of the electric resistance welded steel pipe (ERW pipe)
The external burrs of the steel pipe welds should be removed, and the remaining height should not be greater than 0.5mm.
According to the request of the buyer, after negotiation between the supplier and the buyer, and specified in the contract, the burrs in the weld of the steel pipe can be removed. After the internal burr of the weld is removed, the remaining height should not be greater than 1.5mm; when the wall thickness is not greater than 4mm, the depth of the scraping groove after removing the internal burr should not be greater than 0.2mm; when the wall thickness is greater than 4mm, the depth of the scraping groove should not be greater than 0.4mm.
2. Remaining height of weld of submerged arc welded steel pipe (LSAW pipe)
When the wall thickness is not greater than 12.5mm, the internal and external weld reinforcement that exceeds the original surface contour of the steel pipe should not be greater than 3.2mm; when the wall thickness is greater than 12.5mm, the internal and external weld reinforcement that exceeds the original surface contour of the steel pipe should be Not more than 3.5mm. The super-high part of the weld reinforcement is allowed to be ground.
3. Wrong side
For electric resistance welded steel pipes, the mirror image misalignment of the edge of the steel strip at the weld is not allowed to make the remaining height on both sides less than 90% of the wall thickness of the steel pipe.
For submerged arc welded steel pipes, when the wall thickness is not greater than 12.5mm, the radial misalignment of the edge of the steel strip at the weld should not be greater than 1.6mm; when the wall thickness is greater than 12.5mm, the radial misalignment of the edge of the steel strip at the weld The side should not be greater than 0.125 times the wall thickness of the steel pipe.
4. Steel strip butt weld
Spiral seam submerged arc welded steel pipes (
SSAW pipe) are allowed to have steel strip butt welds, but the distance between the connection point of the steel strip butt weld and the spiral seam and the pipe end should be greater than 150mm. When the steel strip butt weld is located at the pipe end, the spiral with the corresponding pipe end There should be a circumferential spacing of 150mm between the welds.
