UHA-44 1

[MicroEng]

in ASME UHA-44,table UHA-44 ,percent of elongation & Design temp. are input to considering stress relieve or not. but S.S. 316L isn`t in this table .plz explain for me is it a special item?

 

[ijzer]

It is not mentioned because L quality stainless steels are not allowed at high temperature , so recristalization during operating will not occure.

 

[Konrad]

MicroEng,
I raised this issue some time ago on a different forum, maybe som more considerations would be helpful from this thread:

http://www.onetb.com/forum/ftopic181.html

Konrad

 

[metengr]

If you review the list of austenitic stainless steel materials listed in Table UHA-44, you will notice that all low carbon grades are excluded because grain size is not a concern after forming these materials. The low carbon grades have reduced creep strength due to the lower carbon content, and are used in applications where corrosion resistance is required.

For the high carbon grades, coarse or large grain size is necessary, and any warm or cold forming operation will affect grain size and precipitation kinetics in these materials upon exposure to elevated temperature service. Thus, post forming limits are necessary to assure higher temperature strength.