I'm About to embark on the analysis of a 10"
CS Glass Lined Pressure relief piping system

Normally under partial vacuum, but can experience
6.6barg @-29/200c.

Bellows/Graphite condensers prevelent.

Any Pointers from you guys?

Ive asked Pfaudler for the allowables on the Pipework, but they seem to be puzzled as to why i am asking.

WOW your analysis needs to be predicated soley upon the needs of the lining I believe the metal will take more load than the glass lining... you need exact guidance from Pfaudler before doing anything else.

Ask them how much bending dispacement straight pipes can have? and how much ovalization of elbows can take place before the liner cracks?.... that should get them thinking along the correct path....

good luck I'm sure your target numbers will end up being quite low.