background: I have two centrifugal pump non-identical. One is pumping side-draw off a de-C3 tower (P-1) and other pumping overheads from a de-C4 tower (P-2). The product from both pumps combine and go to MEROX. I feel we need a pressure transmitter at the junction so the flow control from one pump will cascade control with a fixed pressure thus you have a steady state flow going to MEROX.
Seem obvious to me but I have the instrument and controls guy that says there is no need for pressure transmitter as both pumps will automatically (magically) arrive at the junction at the same pressure.
I may not have presented the picture as you need it but thanks for your comments.