Seeking guidance on the re-inspection requirements for pressure pipelines
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This post was last edited by ZL668163 on 2024-6-3 at 16:07. I would like to ask everyone: According to requirement 4.32 of GB50235-2010, for pipeline components made of chromium-molybdenum alloy steel, nickel-containing low-temperature steel, molybdenum-containing austenitic stainless steel, as well as nickel-based alloys, titanium, and titanium alloys, material sampling inspections should be carried out using spectral analysis or other methods, and proper labeling must be applied. GB/T 20801.4—2020 5.3 Material inspection: For pipeline components made of chromium-molybdenum alloy steel, nickel-containing low-temperature steel, stainless steel, as well as nickel and nickel alloys, titanium and titanium alloys, the content of major alloying elements shall be checked prior to use by means of spectral analysis (PMI) or other methods. The first of these two standards applies to molybdenum-containing austenitic stainless steel, while the second applies to stainless steel; which standard should be followed?
Not included. 20 steel and S30408 (304 stainless steel) do not belong to chromium-molybdenum alloy steels, nickel-containing low-temperature steels, molybdenum-containing austenitic stainless steels, nickel-based alloys, titanium, or titanium alloys. The requirements mentioned primarily apply to pipeline components made of special materials. .
This post was last edited by Aoki_EXZM on 2024-6-11 09:31. There are many contradictions between these two standards for industrial pipelines; in design, only one of them can be adopted. During the certification renewal process, it was pointed out that it’s not possible to apply both standards simultaneously, and we were instructed to make adjustments by keeping only one of them
The pipelines under our supervision and inspection are required to comply with the GB/T 20801.4—2020 standard