Dear everyone,
My case is heat exchanger - shell&tube type wax/wax+solvent.
Parameters (only pressure considered):
Shell design pressure: 14 bar(g),
Shell side operating pressure (in/out): 4,0/2,5 bar(g),
Tube design pressure: 9,5 bar(g),
Tube side operating pressure (in/out): 6,0/4,5 bar(g).
Tubes diameter 20 mm.
Density is needed too I suppose...
My knowledge of PSV devices tells me that if lower pressure side to higher pressure side is equal to 10/13 ratio, then I don`t need to consider PSV (ASME/API says condition that hydro test pressure of lower pressure side has to be higher or equal to higher pressure side).
In my HX I have lower design pressure side on the tube side and higher design pressure on the shell side. A ratio isn`t enough to meet the 10/13 rule (9,5/14 bar(g)).
Questions:
1) Is a tube rupture case is taken under consideration in case that shell side has higher design pressure than the tube side?
2) How to calculate such PSV relief (I`m asking for advice for calculating PSV relief for tube rupture case for both sides when shell side/tube side pressure ratio is higher than 10/13 and inversely). When calculating relief do I use design pressure or operating pressure?
Regards,
Aider