Interpreting FEA of Turbine Casing

[CSGWB]

We are currently reviewing an FEA analysis of a turbine casing fabricated from plates mitred togther to form a scroll. The FEA indicates that maximum stress intensities develop on the weld of the mitre joint and dissipate into the shell sections. (As would be expected).

We have reviewed ASME VIII Div 2 Appendix 4 but are confused as to which stress category can be applied in this situation and subsequently what allowable stress intensity can be applied.

Can anyone provide me with guidence on this matter, particularly with Websites or texts which may provide additional information to enable a better understanding of the different stress categories and how they can be applied so we can determine the acceptability of this casing.

Thanks.

 

[EMKWR]

Can get you in touch with an expert on the subject but I guess he won't advise you for free.

Edwin Muller
KEMA Power Generation & Sustainables
Arnhem, The Netherlands
E-mail e.f.muller@kema.nl
Internet:

http://www.kema-water.nl

http://www.kema.com

 

[prex]

Though it is difficult to judge on text only descriptions, I think I correctly understood your problem.
Those stresses fall into the category of gross structural discontinuity stresses: they are treated in Table 4-120.1 on the line 'Cylindrical or spherical shell' -> 'Junction with head or flange' -> 'Internal pressure'

prex

http://www.xcalcs.com

Online tools for structural design