i am sizing the relief valve outlet lines. The outlet lines are connected to a flare header where the battery limit back pressure is minimum 2 psig and max of 65 psig.
how do i determine the relief valve outlet lines? At 65 psig max backpressure, this will be used to determine what type of relief valve selection, bellows, conventional, etc. when i make the flare backpresssure to 2 psig, i get a mach number of 1, which forces me to increase the line size. (when i use the 65 psig backpressure, I had no problem with the line size) what is the general practice to size the outlet lines to flare header? what is the rule of thumb for mach number on header and flare outlet lines? for the flare header and subheader, i want 0.5, and for the lateral outlet lines, i want to keep a mach number of 0.7. please let me know.