Modification of pressure vessels in use – change of medium
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This post was last edited by 198498 on 2019-4-3 at 13:55. It is a nitrogen storage tank in use, but the drawings show it as being filled with air. All other parameters are in accordance with the drawings. During the regular inspection, the inspector requested changes to be made. The drawings are in accordance with the standard GB150-1998, Edition 97 of the tolerance specifications. After obtaining approval from a design unit with the appropriate qualifications, is it necessary to prepare new drawings? If drawings are to be produced, should it be based on the original drawings with only the medium changed while all other standards and regulations remain unchanged, or should the drawings be created anew in accordance with the current standards and regulations? Could some colleagues who understand this give some guidance and explanation? Thank you!
Since pressure and temperature remain unchanged, no changes should be necessary!
Only the medium is different; everything else remains unchanged. The inspector insists on making changes, and I can’t argue with him; sigh~~
Generally, it is sufficient for the design unit to issue a letter agreeing to the change
For pressure vessels that are to be modified, with the written approval of the original design unit or a design unit possessing the appropriate capabilities, it is possible to follow the original product standards. It is specified in Article 5.2 of TSG 21-2016.
The requirements put forward by the inspection personnel are reasonable. Although it’s fine to replace air with nitrogen, from a regulatory perspective, changing the medium constitutes a modification to the pressure vessel, and proper procedures must be followed.
It is correct to handle it in accordance with the Safety Inspection Regulations for Fixed Pressure Vessels.
The medium needs to be changed back to that specified by the original design team; furthermore, documents such as certificates and inspection records also need to be updated to ensure consistency
Is this container still in use? Judging by that standard, it should be at least eight or nine years away from now
Handle in accordance with Clause 5.2.1 of the capacity regulations