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According to the industry standard for spiral steel pipes, whether it is a standard spiral steel pipe or a national standard spiral steel pipe, it must undergo flaw detection testing. Some comrades have said that the standard for spiral steel pipes (SY/T5037-2012) is also used? In fact, it's because you don't really understand the Ministry Standard. The Ministry Standard originated from the first production line in China in 1956, which was based on the standards of the former Soviet Union. Although the standard was low, there were requirements for inspection, such as 20% X-ray spot detection. In a sense, it basically meets the production requirements. Generally speaking, the medium conveyed by the Ministry Standard spiral steel pipe is sewage and drinking water. In terms of welding quality, the Ministry Standard spiral steel pipe is pressurized to ensure no water leakage, and X-ray spot detection ensures that the weld is qualified.