When to reject a corroded nozzle 1

[davidnamon]

What criteria to determine how the thickness of in serviced nozzle could continue for service.
Is that correct when the thickness of nozzle to be unacceptable if thickness found by UTM is under the value determine by UG-45? My understand is that the value calculated from UG-45 is the structural minimum thickness but in service pressure vessel the value from UG-45 should minus the value of corrosion allowance. is this correct?

 

[TGS4]

Unfortunately, you are mixing and matching - to your detriment. The ASME Code is a design code, and not a fitness-for-service code.

There are many factors that determine the fitness-for-service of a corroded nozzle, and the ability to withstand the design pressure is only one. I would also examine the nozzle loads, for example.