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is it permissible that i can build a same vessel as build 28 years ago

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stan000

Mechanical
Jul 31, 2014
121

Hello friends
is it permissible that i can build a same vessel as build 28 years ago without changing drawing & calculation.
I can use same CRN Registration but not sure i can use 1990 drawing & cal.
is that mandatory that we have to build as per new code then i have to change drawing & cal.

regards
stan

 
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Absent the CRN, I'd say yes. But the jurisdiction may or may not permit it. Better check with 'em.

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand
 
@stan000, CRNs expire after 10 years. To renew the CRN, you'll need to demonstrate the design meets current codes and standards.
 
Not around here. Even if the vessel design code has not changed, there have been changes to the seismic loading code which will require all new calculations.

 
Yes, you must change drawing and calculations to satisfy the current Code. Depending on how much the current Code has changed from the original Code of Construction Edition, will determine whether a new CRN is required or not. You may be able to ammend the original CRN.

keyen: Only CRNs for fittings expire in 10 years. Vessel CRNs do not expire.

*CRN won't be amended....often is amended when minor (non-calc. required) changes are made, such as nozzle orientations. A lot of companies do not amend when these changes take place, but they are supposed to.
 
replacement to original identical
where i can find out in ASME OR NBIC
you must change drawing and calculations to satisfy the current Code.
regards
 
Even though it is a replacement of an original, it is new construction and therefore Sec. VIII. is applicable. App. 43 tells you that you need to use the current Code, per contract date. Therefore if the drawing and calcs don't satisfy the current Code, they must be changed.

CSA B51 - 4.1.2 - "Any number of pressure vessels may be constructed from a registered design until a change in the Codes or Standards invalidates the design, in which case the design shall be obsolete and no further construction to the design shall be made after the effective date of the change."
 
Assuming an ASME design, you may save money by updating the design- they reduced the factors of safety several years back.
 
The ASTM specs have all been revised . Maybe they have significant changes ,maybe not . but not identical to 28 years ago .
 
ASME Section VIII, Div. 1 Appendix 43 requires the current Code to be used. You can't manufacture a vessel to a 28 year old design unless it is reconciled with the current Code. The current Code is based on the date of the contract/PO.
 
Thanks to everybody
kind regards
stan
 
Now, if the vessel were a shell & tube exchanger, you could order a replacement bundle, order a replacement shell and order a replacement channel and assemble these replacement parts at the site :)

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand
 
I don't agree that updating to the current edition of the ASME Code requires a change to the CRN. The requirements of Sect. VIII are that the construction is in compliance with the current edition of the Code which for a vessel built 28 years ago will almost certainly be because the current Code has higher allowable stresses that the old one.

All I have done in the past is to write right on the CRN drawing and design calculations that they meet the requirements of the 2017 edition, after reviewing the design to make sure that there are no relevant changes.

Building to the previous CRN design may result with a more expensive vessel but this is a commercial decision, not a technical one.
 
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