For a given sustained load case report, how the program is arriving at the code stress from the bending stress and torsion stress given at the left side of SIFs(output report). Please check out the below typical sustained load case of a tee joint(stress units in kPa).
6020(Node no.) 3464.(bending) -853.(torsion) 1.450 / 1.450 (SIF) 5599.(code stress)
The axial sustained stress due to pressure is 2406 kPa.

Correct me if I am wrong, the bending stress mentioned here is resultant of in plane and out plane bending stresses. Using the formula as given in the code we do not arrive at the code stress given here.
For points having SIF=1.0, we get the correct code stress mentioned in the report by using the formula sqrt(bending**2+4xtorsion**2) and then adding the axial suatained stress. Please let me know why the program uses the old method of combining the stresses instead of the one available in the code. And also please let me know why the code stress is not correct when SIF is not equal to one. These calculations are applicable for code B31.1.

Read this thread previously posted.

Dear Richard Ay,
Thanks for the response. I have gone through the thread which you have directed. In fact I had already gone through this thread before posting my query.
In the thread it is mentioned by you that the stresses reported to the left of the "SIF" columns are not directly used in the determination of the "code stress". The "code stress" value is computed directly from the element's forces and moments, by applying the code equation(s).
If that is so what is the significance of bending stresses and torsion stresses mentioned at the left side of SIF. Why the program does not give values which can relate to the code stress. You have mentioned that this is done in the early days to mimic the mainframe programs available at that time. And you are considering changes so that these component stresses are actually what was used to determine the "code stress". Please clear the ambiguity.
It is very uncomfortable when one is not able to get the code stress from the components as mentioned in the report.

There is no significance to the bending stress reported. This is why (time permitting) I want to change it.

If for some reason you want to re-compute the code stress, start with the forces and moments, and apply a the code equation.