For a saturated steam pipeline at 0.7 MPa with a length of about 200 meters, is non-destructive testing necessary?
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For the boiler steam outlet pipe, which carries 0.7MPa saturated steam and is approximately 200 meters long, is non-destructive testing necessary? Pipe diameters are DN50 and DN40
We don’t need such a thin pipe,,,
It’s not necessary to use rays; the booth needs to be set up!
Steam pipes with a DN50 diameter fall under the category of those subject to mandatory inspection; therefore, non-destructive testing must be carried out in accordance with regulations； There is no mandatory requirement for pipes below DN50.
First, it’s necessary to determine what type of pipe it is – GB or GC – as different standards and requirements apply, and these are indicated on the drawings.
We are currently just considering this matter; no design has been done yet. According to GB50184, it falls under Rule V, so no non-destructive testing is required. According to the boiler auxiliary pipes, DN50 is required, while DN40 is not. So, what needs to be considered is which one better fits the actual situation, and which one would be more appropriate to choose.
In May of this year, I encountered a situation similar to the one described by the original poster. The steam pipes we were working on were of GC3 grade, and the design institute specified that no non-destructive testing was required. However, when the special inspection agency came for supervision, they would conduct random inspections of the welds, with at least two welds being checked each time. The construction site was located in Zhenjiang, Jiangsu – this is provided as reference for the original poster.
That’s right, I’m thinking of exactly the situation you mentioned. Depending on the criteria, different situations will arise. So, try to avoid as much trouble as possible.
GB50184 was implemented in 2011; according to the latest GB20801, steam pipes with a DN50 diameter are required to undergo non-destructive testing
That’s the situation; there are many standards involved, and when the Special Inspection Agency uses different standards, different results will be obtained. For example, under the regulations regarding the installation and modification of special equipment, pipes that contain liquids with a maximum operating temperature equal to or higher than their standard boiling point, and whose nominal diameter is 50 mm or greater, are considered pressure pipes. Such pipes fall under the scope of mandatory inspection, requiring non-destructive testing as well as registration.