Brief introduction of
spiral steel pipe technology is as follows:
The first: Appearance quality
1. There should be no cracks, knots, folds, and other defects on the surface that exceed the nominal wall thickness deviation.
2. There should be no craters with a depth of more than 6.4 mm. The length of the pit should not exceed 0.5D. 3. The height of the welded steel pipe should be less than or equal to 3.5mm.
The second: Outer diameter and wall thickness requirements
1. The nominal nominal diameter and nominal wall thickness of the pipeline shall meet the relevant requirements of SY / T6475.
2. The deviation of the outer diameter of the pipe should meet the requirements of Table 1 on page 2 of SY / T5037-2012.
3. The thickness deviation of the pipe wall should meet the requirements of Table 2 on page 2 of SY / T5037-2012.
4. Tube ellipticity requirements: In the range of 100mm length of the pipe end, the maximum outer diameter should not be 1% larger than the nominal outer diameter, and the minimum outer diameter should not be less than 1% of the nominal outer diameter.
5. The pipe end is a flat end steel pipe.
