U-1A Manufacturer Report lists multiple pressure vessels with multiple NB number

[ISDQAQC]

Reviewing a refinery unit's equipment file, I run across an installed and in use Pressure Vessel with a single manufacturer U-1A, Yr. Blt as 2003, manufacturered for a different company, with numerous serial numbers as well as numerous National Board Numbers. The equipment of interest does display a proper data plate with one NB number that is in the range of those listed on the U-1A.

Also in this folder is an identical U-1A with the same conditions that also show a range of serial numbers and NB numbers. however this one has a range as well that could include my vessel of interest but the year built is 2006. Also material grades, diameters, MAWP and Temp are different as well as code year and addenda. Thank you in advance for any assistance.

 

[weldtek]

Per UG 120, identical vessels built for stock or the same owner / agent, hydro tested on the same day, and bearing uninterrupted sequential serial numbers, may be on the same report.

 

[Duwe6]

"Also in this folder is an identical U-1A with the same conditions. . ."
What was the Mfr of each 'set' of vessels? National Board numbers are not unique to the entire planet; they are given in sequence by each Code Stamp holder. Thus every vessel maker had a NB #1, #2, etc. Duplicate NB#'s at refineries are somewhat confusing because of that [we have about 5 'duplicates' at my current site]. But any time you have hundreds on NB registered vessels, duplicate #'s are inevitable. Suggest you start using the [hopefully] unique P&ID equipment number to file your reports and records under.