Deadline issue for pressure vessel drawings
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This post was last edited by Lan Meng on 2009-5-25 at 15:57. Can drawings with official seals still be used directly after being stored for one or two years?
What is a “fairly good qualification stamp”?
Please, be more specific about your question!
The poster is referring to the blueprints that had already been approved with the design seal back in the past. Generally, it is done this way: when it is necessary to manufacture a device for which there were existing blueprints in the past, the blueprints can be redrafted and stamped with the design seal at that time, as the design seal applied then is definitely still valid. A long period of use is related to the issue of renewing the design certificate; if the design certificate has not been renewed, it can still be used.
The design chapter is valid during its expiration period; also, it is necessary to check whether the referenced standards have been revoked. It’s best to first go and check the drawings with the supervision team; if they say there are no issues, then the drawings can be used, thus avoiding disputes later on regarding the failure to provide a report. This post was last edited by zhangzengying on 2009-4-1 07:57]
The design stamps and the standards used must be valid
This relates to the issue of reusing drawings; for design firms, they should apply the reuse management system and affix a reuse stamp. For manufacturing units, there are usually no unnecessary drawings; if such drawings do exist, they should be reviewed to check for any obsolete standards, and if any are found, design changes should be requested from the design unit.
Each set of stamped drawings can be used to manufacture only one pressure vessel. Pressure vessels that were stamped several years ago but not manufactured need to be made anew; they can only be produced after design approval by the stamping authority, otherwise production is not permitted. The Technical Supervision Bureau for batch production of sets of drawings also stipulates that it can be checked.
It is manufactured using old designs; basically, it’s for previous customers who, when upgrading their equipment, feel that the original design is good enough and do not want to make any changes. Our approach is to first have the client confirm the old drawings. Once those are approved, we produce new drawings based on them; the designer makes any necessary changes, and after review these changes are signed on the drawings before the official seal is applied.
Pressure vessels are designed by **design firms designated for this purpose and manufactured by units that hold the necessary qualification certificates; all technical documentation related to such pressure vessels must be archived for future reference. I believe that as long as the drawings have a design seal, they can be used at any time; qualifications are what matter most.
This relates to the issue of reusing drawings; for design firms, they should apply the reuse management system and affix a reuse stamp. It should be noted that the drawings must be used by the design unit while their validity period is still in effect. For manufacturing units, there is generally no issue of having excess drawings; even if such drawings do exist, they cannot be used, as it is not allowed to use the same set of drawings for pressure vessels of different batches!
It is best to request new drawings, as this involves issues such as the validity period of the design firm’s certification and the use of new standards. We have encountered such a problem before: during manufacturing, the qualification of the original design agency was revoked, yet the inspection agency still required redesigned drawings.
Similar issues we have encountered usually involve checking whether the validity period of the design qualification stamp has expired; if it is still valid, then the drawings are acceptable. If the design qualification stamp has expired by the time of container manufacturing, a new stamp issued by the design agency after re-issuing the certification must be used, otherwise the drawings will not be accepted.