Design Code used in Repair/Alteration/Used Vessels
File: N/A
Last Updated: Nov. 19, 2008
SM
When registering a used vessel or a repair/alteration, you must use the correct section, edition and addenda of the ASME Code.
Background:
According to National Board RC-1020 (Construction Standards), if the "original construction is the ASME Code, repairs and alterations shall conform, insofar as possible, to the section and edition of the ASME Code most applicable to the work planned".
Similarly, CSA B51-03 paragraph 11.1 states, "In all repairs or alterations, the methods employed shall retain the factor of safety determined by the ASME Code section referenced when the unit was first manufactured".
Example:
A vessel originally designed to Section VIII-1, 1995 Edition is to be modified and new components added. The 1995 Edition is not available, but material stress values have only changed once in recent times. In the 1999 Addenda to the 1998 Edition, ASME changed the factor of safety from 4 times to 3.5 times, increasing the allowable stress values. Therefore, the calculations for both new and original components are performed to the current code edition (2007 at this time), using material stress values from 1986 (our closest available edition to the original code of construction).
Afterword:
Pressure Vessel Engineering can perform calculations on your used or repaired/altered vessel and help with registration. Ensure that all the paperwork is available to include in the submission package. Original U-1A Form (Manufacturers Data Report), drawings showing modified vessel, photos or rubbings of the original nameplate, UT test reports, calculations and the QC certificate for the contractor performing the work.