Superordinate to the piping and instrumentation diagram is the process flow diagram PFD which indicates the more general flow of plant processes and the relationship between major equipment of a plant facility. During the design stage, the diagram also provides the basis for the development of system control schemes, allowing for further safety and operational investigations, such as a Hazard and operability study HAZOP. To do this, it is critical to demonstrate the physical sequence of equipment and systems, as well as how these systems connect. Modifications are red-penned onto the diagrams and are vital records of the current plant design. The identifications consist of up to 5 letters.
Interpreting Piping and Instrumentation Diagrams-Symbology
Interpreting Piping and Instrumentation Diagrams-Symbology | AIChE
Welcome back to Part 3 folks! Let me apologize at the outset for the delay in getting this posted sooner but we had our Labor Day holiday here in the USA last week and oddly enough, we tend NOT to work on Labor Day. Go figure I suppose it should be called slacker day because I really didn't do much the whole weekend. In any event, I'm back in the saddle so let's recap the last two parts before we hit the trail again. We have a lot of ground to cover before sunset. That's the goal I had when I started this series and by golly, I'm sticking to it.
Process and Instrumentation Drawing Symbols and Their Usage
Hook-up drawing indicates tubing slopes, position of instrument in reference to process tapping point, scope break between instrument vs piping. Hook-up drawing also gives information the requirement of bulk material for each installation. It also details its specification size, type and material and the quantity. This hook-up drawing contains typical installations for instrument which requires instrument air such as control valve, actuated valve Reference drawing: A good designer can also read whether the instrument tapped in gas service or liquid service.
Basics of Instrument Loop Diagrams. Instrument loop diagrams are also called instrument loop drawings or loop sheets. Loop drawings can be customized per customer taste although certain minimum standard information is required to be included in loop sheets. However, the more detail you put into a loop diagram, the easier it makes the inevitable job of maintaining that system at some later date. Typical information you would see on an instrument loop diagram or sheet are: