Allowable Stresses in Sour Service Piping

[chakaad]

In sour service piping some steel grades need to be heat treated after welding and any cold work (such as bending). During stress analysis of some sour service piping we have reached a relatively high stresses in the loop bends. Although the code stress remain withing the allowable range but there are some local yields at the corner of bends. This local yields are permitted by B31.3. But the local yield will be kind of cold work (that should be heat treated) that may cause corrosion and cracking. Do we have to reduce the local stresses to a level below yield stress?