Mixed Phase Flow (Steam/Cond.)

Hi James (and other esteemed piping colleagues),

I've just identified a couple of 250# steam/condensate lines that are mixed phase (flashing from condensate to steam and back again) within my piping system. What are the things that I need to look for when designing this pipe? In the past, I've been forced to re-design control stations to include long-radius bends, laterals, heavier pipe wall, etc.

I know that steam to condensate phase changes form pockets of liquid that may rattle and bang within the piping system. Isn't a considerable amount of energy produced as a result of these phase changes?

Should I go to my mechanical engineer for specific advice?

Thanks,
Bob

It's Process steam, James... DP=290psig, DT=550°F, OP=225psig, OT=500°F in between a 1st stage flash drum and eventually to an atmospheric flash drum. It travels between the two drums through a flow control set about 12 meters from the atm. drum.

Then another steam stream travels from the top of the initial flash drum, through a pressure control set resulting in 40# steam to users.

Thanks,
Bob

hey... thanks very much, James!

Bob