I hope some expert can teach me some technical parameters related to pipes and valves

OP, what era’s these blueprints from? Are you sure you’re not here to ruin things? :Funk: I guess we were all in school at that time! Do a search on Baidu: Steel pipes: Dg80YB804-70, Dg100YB231-70. What are the differences between these two? As for Dg, it is said to be equivalent to DN now, which makes it easier to understand: Dg80 = DN80 pipe, with an outer diameter of 88.9 mm ； YB804-70, thickness tolerance for stainless steel/acid-resistant steel seamless pipes – standard from 1970? Dg100=DN100, outer diameter 114.3mm ； YB231-70, the hardware manual for seamless steel pipes, is also a standard from 1970. For the specific differences, check the standards. Flange: Pg6Dg100HG5010-58; Support: JB/T4725-92; Materials: Q253-A, 0Gr18Ni9; there’s also one with 1Gr after it, I forgot what it is. What are the differences between them? Please advise, experts

Is it an old device that needs to be upgraded????

This way of expressing things is very old; property owners need to keep up with the times~ Dg and Pg are terms from many, many years ago. What was said on the 2nd floor is correct~

The second floor regarding steel pipes has already provided an answer. The flange specification Pg6Dg100HG5010-58 refers to a diameter of DN100; the corresponding outer diameter of the steel pipe is either 114 or 108 mm, with 108 mm being more likely. These are old standards – previously, domestic steel pipes were used, and HG5010-58 is the flange standard, with a nominal pressure of PN6, which means a pressure of 6 kilograms. As for the supports, JB/T4725-92 indicates the manufacturing standard for these supports; this information can be found online. The material specified is Q253-A, which is the material code; if you’re not familiar with it, you can search for it on Baidu, as there are explanations available there. As for 0Gr18Ni9, it’s what’s commonly known as 304 stainless steel. I’m not sure what you meant by the term “1Gr” – I forgot that part

Should Gr be Cr? 1Cr may be a stainless iron such as 1Cr17

It’s a drawing for a graduation project; it’s an old image from 2006, and it’s impossible to find any information about it

Another parameter is 1Cr18Ni10; I’m not sure what the difference is between it and 0

Then you can change it by yourself! Replace it with the material and pipe diameter you consider appropriate. Aren’t today’s graduation projects failing to keep up with the times? At least waiting 10 years should be fine, right?

I don’t understand anything about these materials and such; some materials need to be able to withstand pressure, while others require a specific environment. After looking at them for a while, I felt that the materials used in the entire fermentation tank were not suitable

I used Dg and Pg when helping with design in 1994.