The last weld does not require a pressure test
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In clause 9.1.1 General requirements of the \"Code for Pressure Piping – Industrial Piping, Part 5: Inspection and Testing\" (GB/T20801.5-2006), the relevant provisions regarding d) testing are as follows: 1) Pipeline components can be tested individually or assembled onto the pipeline for testing together with it. 2) The flange joints fitted with blind plates during testing to isolate other containers do not require testing. 3) If the final weld has been inspected during fabrication in accordance with Clause 5.4 of these specifications, and has passed 100% radiographic testing or 100% ultrasonic testing, and if the pipeline system or its components have passed pressure testing in accordance with Chapter 9, then the final weld connecting such pipeline system or components does not require pressure testing. What does the yellow-marked part in the last sentence mean? I don’t understand; please help. O(∩_∩)O Thank you
This post was last edited by xlxuiin on 2016-12-18 at 18:57, with non-destructive testing used in place of hydrotesting. See 9.1.7
There is such a specification: for example, for the last weld at the tie-in point, since a pressure test cannot be carried out, non-destructive testing is used as a substitute.
I’m not very familiar with this area; I don’t know what the specific standards are
GB150 also contains relevant regulations; for pressure pipelines, which are similar in nature to closed systems, the procedures for handling the final weld are specified in the same way in both standards.
It can be used for non-destructive testing, as a substitute for hydrostatic testing
With these supplementary measures, the quality of the welds can be adequately ensured, demonstrating the unity of scientific rigor and flexibility in the formulation of the standards
When a hydraulic test cannot be carried out on the last weld, ultrasonic testing or eddy current testing can be used as a substitute for the hydraulic test on electric welded steel pipes, while ultrasonic testing or radiographic testing can be used as a substitute for the hydraulic test on submerged arc welded steel pipes.
100% flaw detection, namely the so-called gold weld seam, using flaw detection in place of hydrotesting