PWHT "Nominal Thickness" 1

[PipingEquipment]

I am attaching a nozzle with a through fillet (P-1 material), the sizes of the fillets are 3/4" on one side and 7/8" on the other, there is abate in the office as to whether this has to PWHT or not, it looks to me under UW-40(f) that the nominal thickness is taken as the largest fillet, another argues its the sum of fillets, can somebody help clear this up?

.Thanks

 

[stanweld]

My first question is, "What is a through fillet?" 2nd "What is the base metal thickness?"

 

[PipingEquipment]

Base metal thickness is 1.88" (its a 10" sch 160 pipe through the center of a 24" 150# blind, both CS) and a through fillet is a connection with no groove weld and fillets all the way around each side.

 

[VeryPicky]

I would go with a sum of both fillets' throat thicknesses. UW-40(f)(3)

Putting Human Factor Back in Engineering

 

[PipingEquipment]

This is the section I was using, it says; "For fillet welds the nominal thickness is the throat dimension. If a fillet weld is used in conjunction with a groove weld, the nominal thickness is the depth of the groove or the throat dimension, whichever is greater."

To me "the throat dimension" indicates one weld is used, it doesn't say "dimensions", or "the sum of" also after that it indicates that if a groove and fillet are used then take the nominal of only one of them (the one with the greatest thickness). I would think if they wanted the sum of the fillet wleds to be used then they would say that, but they simply say the "throat dimension", again singular.

 

[metengr]

The nominal thickness in the above and UW-40 (f)3 pertains to the fillet weld with the largest throat dimension. Other fillet welds which have a lesser throat dimension go along for the ride if PWHT is required.