Dear all
While design flange calculation as per Appendix 2, one need to use lower allowable stress in case of ASS material (code gives two values one bsed on 90% and another twp -third of yield).

As per code one has to use lower allowable stress for flange design as per Appendix-2. However when thickness at small end is calculated as per UG-27-C, one can use higher allowable stress based on 90% yield.

But PV Elite uses lower allowable stress while using t= PR/ (SE-0.6p) for hub smaller end. Can some body comment on the same

Thanking You and With regards

Dear Mr. Srinivasan,

You have a very good point. This provision is already available in PV Elite, there is a check box on the flange dialog "Are the Hub and Attached Shell Materials the Same?". If you check this box then the program will use the allowable stress of the attached shell (for which you will be using the higher allowables).

These allowables will be used for the small end hub calculations.

Refer to attached screen shot.