Firstly, oil marking should be carried out. For some qualified steel pipes, oil should be applied to prevent corrosion. Therefore, the manufacturer needs to mark according to user requirements during this process.
Secondly, it needs to be leveled and milled. Here, the original curled steel plate needs to be flattened by the anvil, and then the two edges of the steel plate are milled on both sides by the milling machine to achieve the required plate width and parallel plate edges. Degree and groove shape.
In addition, a visual inspection is required. This is a reasonable inspection of some basic parameters by professional technicians to ensure the quality.
Then ultrasonic flaw detection is required below, and 100% inspection should be carried out for the inner and outer welds of the anticorrosive spiral steel pipe and the base metal on both sides of the weld.
The last point is to perform X-ray inspection, which also requires a 100% X-ray industrial television inspection of the inner and outer welds. This generally uses an image processing system to ensure the sensitivity of the inspection.