Nozzlepro Occasional Load Factor

[Ed555]

Hello,

I spoke with Nozzlepro regarding the occasional load factor for wind or seismic. They are giving the default k=1. There is an option for k=1.2 but they said the ASME 2019 and later now requires k=1. If there is no allowable stress multiplier for occasional loads, is there any sense in running the nozzles loads including wind or seismic as occasional anymore?

Thank you.

 

[KevinNZ]

Are occasional load stresses calculated at operating pressure rater than design pressure? This is case for piping, but not sure for pressure vessels.

 

[TGS4]

Ed555 - you state "ASME 2019". Which Section and Division of the Code are you referring to? That will inform an appropriate response.

 

[Ed555]

If using Section VIII Div.1 for the pressure vessel design, but using the rules of Div.2 for the nozzle loading FEA, can the UG-23 1.2 allowable stress multiplier be used for the occasional loads (wind or seismic) allowable stress? I believe if using the rules of Div.2 for Div.1 calculations you still are required to use div.1 allowable stress values.

 

[TGS4]

Ed555 - I see that you are constructing your vessel to ASME Section VIII, Division 1. Please review the rules in Appendix 46 to reveal the answer to your latest question.

Note that when you follow the rules from Appendix 46, you use the load case combinations from ASME section VIII, Division 2, Part 5, which have the occasional load factors for wind and seismic already included, but not as a "higher" allowable stress, but as a partial load factor.

 

[Ed555]

TGS4: Thank you. Appendix 46 makes it clear.