flowsheet sovrapposto a layout

[Kaji]

Save in the technical office of the company where I work as outside I was assigned, I do not know whether temporarily or not, the task of "work" the drafting of the flowsheet after the one who followed them has dismissed (ten discharge in 4 years in an office of 7 stations.. ); my task I think will be purely annotative since I have never dealt with flowsheets and as said I am external, but the first thing that left me very surprised is the fact that the flowsheet provided me is in fact superimposed to the layout and therefore is a jungle of lines according to me of difficult understanding since in the end the cetop symbols of valves etc become high a few mm.
I was wondering if it was a common practice in industrial plants that could be handled with layers etc.

 

[ian3d]

overlaps with the layout perhaps because it is used both as a process diagram and as a mounting scheme.
I don't deal with flowsheets and I don't know exactly the drawing rules that rule them, but those I see show only the process schematic and are not overlapping to the plant layout they refer to.
the use of layers or blocks is a free choice for convenience of drawing, printing and, possibly, for business standards, if they exist.