SA-182F316L low stress material
SA-182F316L low stress material
(OP)
While designing a kettle type heat exchanger, I am having a confusion if I should use low stress material for body body flange and tube sheet.
Also which are the scenario where low stress material should be used, I have read note G5, still having a curiosity to know in actual industry where low stress material is preferred and where high stress material can be used.
Also which are the scenario where low stress material should be used, I have read note G5, still having a curiosity to know in actual industry where low stress material is preferred and where high stress material can be used.





RE: SA-182F316L low stress material
Regards,
Mike
The problem with sloppy work is that the supply FAR EXCEEDS the demand
RE: SA-182F316L low stress material
RE: SA-182F316L low stress material
For me deformation in shell during operation could cause more damage to flange connection.
RE: SA-182F316L low stress material
Aside from client specs it is your choice what to use where, but use of lower allowables for flanges, etc. and higher allowables for everything else is very common.
I will add that if a gasketed joint leaks due to distortion of the members of the joint, you are done. Not repairable.
Regards,
Mike
The problem with sloppy work is that the supply FAR EXCEEDS the demand
RE: SA-182F316L low stress material
RE: SA-182F316L low stress material
Regarding the two lines with stress values per st/st grade (ASME II Part D tables): We used the lower values only where it is critical to minimize deflection (e.g. flanged/gasketed joints) or when specified by clients.
I find the last question by the OP an interesting one as I have not seen this approach before. It could result in a slight reduction in flange thickness? Whether or not it would be worth the risk of possible sealing issues during testing is debatable.
RE: SA-182F316L low stress material
anything above operating condition should be incidental, causing material exposed to higher tension for short period of time at certain operating temperature.
or else we can multiply operating condition with certain factor for eg. 1.25 or 1.15 and check design based on amplified values.
RE: SA-182F316L low stress material
As an alternate approach, why not used dual certified material, and then use the lower allowables of straight grade (non-L) material?
Regards,
Mike
The problem with sloppy work is that the supply FAR EXCEEDS the demand
RE: SA-182F316L low stress material
RE: SA-182F316L low stress material
On further discussion regarding this with our AI, conclusion is as below,
These different stress values have been RECOMMENDED for SS materials where bending stresses are predominant.
I feel the manufacturer should have good knowledge and strong justification for use of higher allowable stress where bending stresses are governing. He may demonstrate this by performing alternate calculations.
Regards,
Stephen