A Process Flow Diagram - PFD - (or System Flow Diagram - SFD) indicates the relationship between major components and parts of a system. A PFD tabulates process design values for components and systems in different operating modes, typical minimum, normal and maximum values. A PFD does not show minor components, piping systems, piping ratings or designations.
A Process Flow Diagram - PFD - should include:
- process piping
- major equipment symbols, names and identification numbers
- control valves and valves that affect the operation of the system
- inter-connection with other systems
- major bypass and recirculation lines
- system ratings and operational values as minimum, normal and maximum flow, temperatures and pressure
- composition of fluids
A Process Flow Diagrams - PFD - should not include:
- pipe classes
- pipe line numbers
- minor bypass lines
- isolation and shutoff valves
- maintenance vents and drains
- relief and safety valves
- code class information
Documentation of process control systems - Block Flow Diagrams (BFD), Process Flow Diagrams (PFD), Piping and Instrumentation Diagrams (P&ID) and more
The Process Flow Diagram (PFD) is a schematic illustration of a system.
Draw Process Flow Diagrams with this online Google Docs drawing application.