How to distinguish between A333 and steel pipe No. 20

Almost the same corrosion condition; I would also like to ask experts for their insights

It seems that spectral analysis can’t determine it, right?

This post was last edited by tjsyhx@163.com on 2019-3-31 at 17:33. Edit: L. Your question is ambiguous and needs to be clarified: one of the things you’re asking about is the code for the execution standard, and the other is the code for the material. What are the two of them going to compare? If I’m not mistaken, you’re asking about the differences between A333 Gr.6 pipes and GB/T 8163 20# steel pipes, and how to tell them apart ! For steel mills as well as our sales companies, they all fall under the category of carbon steel. In terms of standards, one is to follow the American standards for seamless and welded steel pipes used in low-temperature applications, while the other is to adhere to the Chinese standards for seamless steel pipes used in low-pressure fluid systems. In terms of production, A333 requires to be delivered in the normalized state, while 8163 is mostly delivered in the hot-rolled state; whether normalization is necessary depends on negotiation between the supplier and the buyer. In terms of usage, the main difference as indicated by the standards is that one is designed for low-temperature conditions, while the other is suitable for low-pressure fluids in general. In terms of their chemical composition, the maximum values for carbon and manganese content in ASTM A333 GR.6 are higher than those of China’s 20# standard; moreover, since it is delivered in a normalized state, its low-temperature impact performance is significantly superior to that of the latter! ! In summary, to actually distinguish between the two, one can only do element analysis as well as mechanical and low-temperature impact tests. For a simple assessment, there are the following points, which I hope will be helpful to you: 1. Purchase products manufactured by reputable manufacturers; such manufacturers apply markings to each steel pipe before it leaves the factory, and these markings are clearly visible. Usually, there are 2–4 factory labels per bundle of steel pipes. 2. For market purchases of ready-made products, it’s of course better to turn to stable suppliers with whom there is a long-term partnership; only rely on reliable and reputable suppliers to obtain the goods, as this ensures consistent and guaranteed quality. As for the price, it can be negotiated. 3. Improve one’s ability to identify materials; fake products on the market can be detected by experts right away due to their flaws. Here is a photo of an A333 Gr.6 tube taken at work for reference.

This rapid identification relies entirely on the manufacturer’s markings. . To make the correct identification, it is necessary for tests on composition, mechanics, impact, etc. to pass.

A333 specifies that it must be delivered in the normalized condition

#4 explained it in quite detail; it’s impossible to tell the difference with the naked eye