Dear Friends,

While analysis of one system,we had doubt as below.

SC = 137.892 N/mm2
SH = 118.433 N/mm2

Without Considering liberal (Eq 1a) = Allowable = 202N/mm2

With Considering liberal Eq 1b = Allowable = 316.8 N/mm2

2nd Case, addition of (Sh-SL) when Sh is greater than Sl (as per code). How we came to know Sh > SL.?

Q -1) If considering above shown values, should I mean to count that "SL" shall be 118.4 N/mm2?


Q -2) Sl = Sustained Stress.I checked in Stress Summary report, sustained stress is not 118.4 N/mm2......This is actually "SH". So, when SL is quiet low, do we consider SL=SH for Eq 1-b calculation?

Q-3) Sustained stress shall be different at all support locations, however Allowable of Expansion case in Liberal (eq 1-b) is same at all locations.

Thanks in advance.

Dear Azley,

If liberal stress ON-

The sustained stress varies from one pipe to another; the allowable expansion stress will also vary.

Calculation of liberal stress allowable value:

SC & SH you already know,

FROM CAESAR RESULTS: Select  SUS CASE  Stress extended  CODE STRESS is SL. At a particular element.

FROM eq-(b) SA= 1.25*f(Sc+Sh)-SL . CALCULATE SA for a particular element.
Rememeber the allowable expansion stress will vary for element to element.

May be this is helpful for u.

Any thoughts on this..