Process Flow Diagram or Piping and instrument diagram
For an engineer, the drawing is everything. An engineer must understand all drawing i.e Process Flow Diagram (PFD), Piping and Instrument Diagram (PID), Isometric drawing, engineering drawing, manufacture drawing, welding-map drawing or As-built drawing. Engineer who cannot read drawing can be considered as a blind engineer. Which drawing is the most important? Every drawing is important, depending on the purpose we use it.
PFD-Process Flow Diagram is a helicopter view of a plant. From this drawing, we can see the production process in general, the stage of production and capacity in every process. If we have just hired in a plant, then the first thing to look for and learn is PFD – Process Flow Diagram.
Piping and Instrument Diagram
The second stage of understanding the PFD-Process Flow Diagram, we should be able to read the PID-Piping and Instrument Diagram. In this drawing we can see all equipment installed, “process piping” used to connect between equipment and instrumentation used to control process at plant. PFD-Process Flow Diagram is the deliverables of the process engineer while PID is the result of a collaboration of all disciplines engineer.
If you can understand all the things written on the PID-Piping and Instrument Diagram, then you can operate the plant easily. we often encounter problems in the production process and we do troubleshooting using PID-Piping and Instrumentation Diagram.
The third thing that must be understood by a mechanical engineer is isometric drawing. Here we can see detail pipe installed in the plant. Information that can be known is pipe size, pipe material used, pipe length, the type of pipe connection and gasket used. Each pipe drawn in the isometric drawing is labeled reflecting the previous information and also the fluid flowing in the pipe.
if we find a problem in the pipe e.g pipe corrosion, then the first thing to do is learn PID and isometric drawing. From these drawing, we can prepare the pipe replacement project.