Making Two Vessels From One - Code Issues?

[UW1981]

We have a situation where two vessels were made from a longer vessel. The original vessel was built in 1967 and was code stamped (we have the drawings). The vessel was cut in half and two vessel were constructed using new heads for each...both vessels were R stamped for the modification.

The question is...are both the newer vessels considered "code"....I believe they are since we have the pedigree information, though they may share the same National Board Number (ie, the number that was on the orignal vessel).

Any input/thoughts would be appreciated.

 

[deckie1026]

metengr;I certainly appreciate your comments.If I were involved in this project, I would hire a reputable R stamp certificate holder. If I were the AI, I would require a PMI to be conducted as well as UT thickness gaugings. I would require calculations to be produced in accordance with the ASME Code in effect in 1967. Calculations would use the most conservative joint efficiency. Notwithstanding the above, I would require 100% RT of the head to shell joint. I would require a hydrostatic test. If all was satisfactory I would sign the R-2 after the R stamp holder signs. I beleive the above is in acordance with the NBIC. Texas is not a Section VIII state and there are no state specials. My comments are for this particular situation only.

 

[UW1981]

I appreaciate all the comments and discussion....I did find out that the vessel in question DID have an original "U" stamp.

Here is an excerpt from a NBIC 1992 Addenda that provided some guidance at that time, but from I gather, the NBIC has backtracked from this position (though I have not seen anything in writting dated relative to this issue dated after this).

MAKING ADDITIONAL PRESSURE VESSELS FROM ONE VESSEL
From time to time, jurisdictions may receive requests to accept pressure vessels which have
been made from one larger vessel; i.e., two or more additional vessels have been made from
one ASME/NB stamped vessel.
The following guidelines were developed by the NBIC Committee and approved by the
National Board Board of Trustees. They are intended to be used as a guideline by National
Board member jurisdictions, if those jurisdictions choose to accept the installation of such
vessels.
1. The application of these guidelines are intended to be restricted only to ASME Section VIII, Div. 1 "U"/NB stamped pressure vessels provided the additional vessels made from the original remain in the same service as the original with no increase in the stamped MAWP or temperature.
GUIDELINES
2. The following requirements shall be met:
The original pressure vessel was constructed in accordance with Section VIII, Division 1 of the ASME Code, stamped with the "U" Code Symbol and registered with the National Board.
The original pressure vessel shall be inspected in its present condition by an Authorized
Inspector to determine whether the condition of the vessel is suitable for the stamped pressure, temperature and intended service.
Parts removed from the original pressure vessel to be used on the additional pressure vessels shall be identified so that they may be readily traced to the original vessel.
All additional parts used to construct the additional vessel(s) shall be new and shall meet the requirements of the NBIC and Section VIII, Division 1 of the ASME Code.
The fabrication, welding and inspections shall be in accordance with the requirements of Section VIII, Division 1 of the ASME Code.
The final design of these vessels shall meet the requirements of Section VIII, Division 1.
A Form R-1, Report of Alteration, shall be completed for each pressure vessel. This form shall cover in complete detail the additions to the additional new pressure vessels and deletions from the original pressure vessels.
The original pressure vessel and the additional vessel(s) shall be marked in accordance with this Code except as follows:
1) Other than for dimensional differences, the nameplates on the additional
vessel(s) shall be, except as required in 2,3 and 4 (below), identical to the nameplates on the original pressure vessel and shall bear the words "REPLICA-SEE ALTERATION NAMEPLATES" immediately preceding the National Board registration number.
2) The nameplates shall bear manufacturer serial numbers or alteration numbers such that each individual additional vessel(s) may be identified with the original
pressure vessel.
3) Each pressure vessel shall bear a unique identification number. The method of identification shall be recorded on the Form R-1.
4) The ASME Code Symbol stamp shall not be applied to the additional pressure vessels.
The manufacturer making alterations under the provisions of this paragraph must possess all documents required in the fabrication of the original pressure vessel, including, but not limited to, the manufactureis data report, mill test reports, inspection records, and nondestructive examination records