Dear experts,

I am using C II ver.5.3. Quick Reference guide is saying that,

in B31.3, Sl = Slp + Fax/Am + Sb

As long as I know, before B31.3,2010, there is no mention about longitudinal stress in B31.3 but 31.1 (para. 104.8.1/2)

At B 31.3 2010, para.320.2 is showing Sl which is different from that of Quick reference guide.

Where does Sl = Slp + Fax/Am + Sb from?

(if your answer is...'that is from operating stress in same QRG', then, where does operating stress equation from?)

Hi kagemaru,

longitudinal stress is defined as sum of stresses ( due to pressure + due to force + due to bending moment)

this defination is clearly mentioned in ASME B31.3 (old version)

Now in latest version longitudinal stress involves torsion also. ( by using 178 code in config file - sif )

if u click on that 178 in sif-stress option then CEASAR use

sl=sqrt((sa+sb)^2+(2st2)).

now for operating case click on APPENDIX-P , caesar calculates operating stress by using so=sqrt((((sa+sb)^2+(2st2)) check in APPENDIX P in B31.3.

Regards,
DURGA

Thanks durga!!

As you mentioned, I checked b31.3 APP.P for operating stress.

and also checked b31.3,2010(latest as long as I know).

I knew SL was firstly mentioned in b31.3 at 2010 press. that is why my

question arise.

at B31.3,2010, SL=sqrt((abs(Sa)+Sb^2)+(2St)^2). before b31.3,2010, I

used to use SL from B31.1, para320.2, SL = PD/2 +0.75iMa/Z



Again, my question is....

SL in Quick reference guide is different from B31.1 and also different

from B31.3,2010.


where does SL equation in quick reference guide come from?

and why is it same as operating stress in quick reference guide?

B31.1 provided an explicit equation for SL, so that's what we used in CAESAR II.

B31.3 on the other hand never provided an equation, just a verbal statement. The equation in the QRG is our interpretation of that verbal statement.

NOTE, B31.3 2010 is not addressed in CAESAR II, since this edtion of B31.3 was released after CAESAR II 2011 (v.5.30).

Thanks Rich.

Everything is clear!!!

Hi Richard,

Is there any plan to include B31.3 2010 changes to CAESAR 5.3?

Regards,

No, not in v.5.30, that is already released. The 2010 edition will be addressed in the next version, v.6.00.