Hi all
I have been using CAESAR and really get confused about
Load case "1 (OPE) W+P1+T1" Code Stress

Here is an example of calculated data
Piping Code: B31.4
Fully Restrained Pipe
Axial Stress: -915.1 kg/cm2
Bending Stress: 2.7 kg/cm2
Hoop Stress: 2859 kg/cm2
W = 0 (buried pipe)

Code Stress Calculated by Caesar: 4337.1 kg/cm2
How? (?_?)

This case, equivalent Von Mises stress become
Se = 3409 kg/cm2
I am really confused how this code stress is lead.
Am I missing something?
Please let me know equation to calculate Code Stress
for load case 1 (OPE).