Stress relief of A106 at ambient conditions
Stress relief of A106 at ambient conditions
(OP)
I have a piping system constructed of A106 carbon steel pipe. This piping is too constructed per ASME B31.1 piping code. The nominal thickness is greater than .750” thus requiring heat treatment per the code. This piping was constructed in the year 2000 and has not seen service. We have no record of heat treatment being performed. I have been told by a metallurgist that over time this material will stress relieve itself, and thus stress relief is not required on this particular piece of piping. Has anyone ever heard of natural stress relief at ambient conditions? The service of this piping will be 650# steam.. I am going to have this piping heat treated per the code for documentation and liability reasons, but I am curious if there is any merit to what I was told.





RE: Stress relief of A106 at ambient conditions
RE: Stress relief of A106 at ambient conditions
RE: Stress relief of A106 at ambient conditions
Putting Human Factor Back in Engineering
RE: Stress relief of A106 at ambient conditions
For cast iron beds used for precision machinery like jig borers etc., it has been the practice to get the beds rough machined and leave it in the open atmosphere for 3-4 years for 'natural ageing' to take place. Such beds have been found to retain its accuracy and free of distortion for the life of the machine. Though modern tendency is for thermal stress relief of the beds, some manufacturers would go in for this tested path than turn modern.
Regards,
MRCN