Allowable nozzle loads are based on mechanical strength of equipment/nozzle interface (except ratary equipment, where it is governed by shaft misalignment and casing distortion). As per B31.3, allowable stress in occasional load is 1.33Sh, i.e Syeild. So, allowable nozzle load in occasional case may be 1.33 times higher.

For rotary equipment, it may be 1.2 times higher allowable (corresponds to 0.9Sy). I know, no code specifies this.

Your suggestion please.

Regards,

So far static equipments are concerned, I would go for the design by analysis route of Sec VIII DIV 2 APPENDIX 4.It clearly address the question of occasional factor for allowable stresses.Regarding nozzle flexibilities, I would go for WRC 297 or an FEA analysis.

For roraty equipments, a simplistic solution is never recommended.Vendor's concurrence is always required.

Regards

.............and remember that there will be more flexibility than you are calculating. Modeling equipment attachment points as "anchors" is conservative for static loads but not so for dynamic loads. When B31S is available it will be a source for guiding the design of piping systems for dynamic loadings.

Regards, John.