What issues exist with welding on carbon steel lines that have been in anhydrous HCL service for 25 1

[dutch1956]

What safety & failure issues do I have to be concerned about on welding on the subject matter above.
If welding is not the route can lock ring flanges be used in this service.

 

[metengr]

Are you referring to a hot tap process or off-line, fully vented pipe system?

 

[dutch1956]

This line is off-line fully vented.

 

[metengr]

I don't see any weldability or safety issues. Make sure the weld preps have been cleaned and subject to NDT examination (surface) before welding.

 

[dutch1956]

Thanks Metengr

 

[phighfill]

I have noticed in the past that there are possibilities of subsurface discontinuties opening up under welding process. So I think that a UT thickness check of about 6" around the welded area be checked prior to welding.