I would like to ask the teachers what material and grade should be used for butt-weld flanges, given that the pipe material is CS carbon steel and the medium is water.
Thread Content
I would like to ask the teachers what material grade should be used for butt-welded flanges, given that the pipe material is CS carbon steel and the medium is water. The requirement for the flange is that it should be of the same material as the pipeline; should 20Ⅱ steel be chosen? Still Q235B steel? Thank you
It just needs to be consistent with the pipeline; the pressure-bearing capacity of the flange is greater than that of the pipeline
It just needs to be consistent with the pipeline; the pressure-bearing capacity of the flanges is higher than that of the pipeline. It’s fine to find a welder with good skills
Okay, thank you. Which is better, 20Ⅱ steel or Q235B steel?
Okay, thank you. Which is better, 20Ⅱ steel or Q235B steel?
20# steel is a low-carbon steel plate, while Q235B is a plain carbon steel plate; the difference lies in their material properties. 20# steel has lower hardness but better weldability, according to what I’ve found. I’ll ask relevant personnel for more details
The last edit to this post was made by zxhslm on 2018-3-15 at 10:53. The requirements regarding flange materials in HG/T20592-2009 are listed in Table 4.0.1, Note 1: “Flange materials should generally be made of forgings or castings; the use of steel plates is not recommended.” Steel plates can only be used for flange covers, lined flange covers, plate-type butt-welded flanges, socket weld ring loose-flange types, and butt-weld ring loose-flange types. If it is a proper design document, the materials should be specified. Based on the information provided by the poster, it can be determined that 20Ⅱ will be used. 20Ⅱ refers to 20 steel, grade II forgings, with the forging standards in accordance with those specified in the flange standards.
In detail, we also use 20592, but we’ve actually never used Q235; I hadn’t noticed it until now