What is Difference Between of PFD & P&ID?
Process Flow Diagram (PFD):-
A Process Flow Diagram (PFD) is a simplified representation of the major components in a chemical process. It illustrates the relationships between key equipment such as columns, vessels, pumps, turbines, and heaters.
The PFD focuses on the flow of chemical fluids through these major pieces of equipment and includes essential properties of these fluids like temperature, pressure, density, and flow rate.
However, it does not provide details about minor components such as pressure and temperature instruments or piping systems. The primary purpose of a PFD is to give an overview of the entire chemical plant processes without delving into intricate details.
Key elements typically included in a PFD are:-
Main equipment symbols Major process piping System ratings and operational values(pressure, temperature, flow rates) Interconnections with other systems.
Piping and Instrumentation Diagram (P&ID):-
In contrast, a Piping and Instrumentation Diagram (P&ID) offers a much more detailed view of the process.
It encompasses both major and minor details necessary for understanding how the system operates within the overall plant context.
A P&ID includes comprehensive information about piping specifications (size, material), instrumentation details (pressure gauges, control valves), control loops, utility lines, drain lines, vent lines, sampling lines, isolation valves, and more.
This diagram serves as a critical document for engineers involved in procurement and material sourcing as well as for determining pipe routing.
Key elements typically included in a P&ID are:–
Detailed instrumentation designations , Mechanical equipment names and identification numbers All valve identifications Process piping sizes and identification Flow directions Interconnections references Comparison Summary While both diagrams serve important roles in chemical engineering projects—providing essential information at different stages—they differ significantly in detail level.
A PFD provides an overarching view suitable for initial design phases while a P&ID offers intricate details necessary for construction and operation phases.
The need for both diagrams arises from their distinct purposes:- PFDs are primarily used during design proposals and maintenance phases. P&IDs are crucial during conceptualization, procurement, manufacturing stages