U have shown 2 separate Steam Lines with PRVs .The steam supply system will be as under :

1. Main steam line will come from boiler to the plant .Steam pressure =10kg/cm2

2.The pressure will be reduced from 10 Kg/cm2 to 3 Kg/cm2 by using PRS.

3.The steam will be distributed further from a common header (after PRS )  as per requirements of steam ( Pressure and Quantity )