You could try fluorinated polymers. Probably not Ptfe if the stress is permanent, but stronger ones like Efte, Pctfe. Have a look in a list of fluoropolymers, I don't have my doc here. They aren't very cheap neither.
I didn't expect phenolic to operate at 150°C HCL.
First of all thanks for the reply,
I am a newby to industry, appologies for the confusion created.
let me clarify
the follower pipe will not be in contact with 20% HCl at 150'C permenantly,
1. The acid/steam inlet pipe goes through the follower pipe (the clearance between the two is only 1.5mm). During operation the inlet pipe will get heated as much as upto 150'C, obviously the follower pipe also get heated to temperatures near to 150'C. that is a safe approximation i took.
2. Acid resistance propery for the follower pipe is desired since we dont want to replace the follower pipe for minute/ dropwise leak of HCl through the packings.
That is the follower pipe will be in elevated temperatures, when acid gets contacts with it.
hope this clarifies.
Also i ll go through the material you have specified.
Again thanks for the post