First of all, we're located in Russia => we have to work with GOST (russian state standard), but you can make family table with necessary B16.5 flanges and insert it as "fittings". This package costs for us about 10 k$ for 1 workplace (only Pro/Piping!!!). All equipment (valves, compressors, pumps etc.) were made ourselves - they did not included in package. About ACAD.... hmmm.. - we'd canceled work with this programm as soon as we knew all advantages of Pro/E. Main advantage is your CONSTRUCTING (NOT DRAWING, painting, waiting for redrawing and regenerating etc!!!) Pro/E is designed to work with solids but not with simple lines(as you know). Problems... they always have place to be ))) - but these problems are NOT SO LARGE as ACAD..
I've sent you a jpg-file - This construction have taken me about 1.5 week - and it'll take me about 1 week to make documentation for welding, soldering and mounting - not so much (sorry for my english)