P&ID diagram
A P&ID documents process plant: vessels, pumps, valves and the instruments that monitor them, using symbols that are standardised for a reason.
The shapes ship with the draw.io editor, so the diagram lives on the page rather than in a CAD file only one person can open.
#When to reach for one
Process and manufacturing documentation.
Maintenance procedures that reference specific valves and tags.
Handover documents where the notation is expected.
#How to draw it in Capable
Route | Use when |
|---|---|
draw.io | The P&ID shape libraries, laid out by hand. |
Excalidraw | A sketch for a discussion, never for a controlled document. |
#Symbol families you will need
Family | Examples |
|---|---|
Vessels and equipment | Tanks, columns, heat exchangers, pumps |
Valves | Gate, globe, check, control, relief |
Instruments | Indicators, transmitters, controllers, with tag bubbles |
Lines | Process, instrument signal, pneumatic, electrical |
#A few things that catch people out
Tag numbers are the point. A P&ID without instrument tags is decoration.
Line types carry meaning: process, signal, pneumatic and electrical are not interchangeable.
Keep the legend on the diagram. Readers will not have the standard to hand.
#Related
Somebody will read this at 3am. Be kind.
