Questions about the selection of hydrogen-resistant material ANTI-HIC
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Hello fellow seniors, there is currently a project where the customer requires that some of the carbon steel materials be: CARBON STEEL ANTI-HIC. Including plates, pipes, flanges, etc. Design pressure 1.0MPag, design temperature -19℃ to 250℃, the problem is as follows: 1. Regarding the selection of pipe fittings, the customer requires standard GB/T 9948, and the material is 20# steel ANTI-HIC, but GB150 stipulates that the lower limit of the use temperature of 20 steel is 0°C. My idea is: Can you just choose GB/T 9948 20# steel pipe, but the supplier is required to do a -20°C low temperature impact test. If not, negotiate to change to other standards such as GB/T 8163 Q345D material, etc. 2. Regarding flange selection, the flange is to be made of 20# secondary forgings. When ordering, it is required to conduct -20°C low-temperature impact test and hydrogen-induced cracking resistance HIC test in accordance with the standard NB/T 47008. Is there any problem with this? 3. For materials: Carbon steel ANTI-HIC In addition to specifying when ordering, such as 20 steel (HIC), Q345D (HIC), what else should we pay attention to? Where can it be shown on the quality certificate that it is a hydrogen-resistant material? Element content? Mainly because they are afraid of suppliers cheating. . . I hope experienced masters can give me some advice, thank you very much.
It should be because it is so complicated. The Nace standard has requirements for material components. If it doesn't work, just do an HIC test and provide a test report.
Hello, I checked NACE MR0175. The standard has requirements for the S content in HIC-resistant steel (as shown in the screenshot). However, I learned from the Internet that HIC-resistant steel also has requirements for the P content, but I did not find relevant instructions in the standard. Can you give me some suggestions? Please give me some advice, thank you
When I was working on PetroChina projects, their technical specifications generally had requirements for the material components of A105. Valve manufacturers could almost meet the requirements without any major problems. I didn’t pay special attention to the P content. In short, for raw gas with high sulfur content, specifications generally also require carbon steel to provide HIC/SSC test reports.