CAD PFD differentiation
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What is the name of that set of drawings that includes gauges? Is it CAD? Is PFD just a simple flow chart?
A process flow diagram with control points is called PID. A PFD is called a material balance diagram; in addition to the main process flow, it also includes data on material balances.
According to the standard terminology, a PFD is a Process Principle Flow Diagram that includes the main process flows and the most basic process control requirements. It also contains data such as material flow names, temperature, pressure, flow rates, as well as information on the heat loads of heat exchangers and heating furnaces; however, it provides less information regarding instruments. A P&ID is a process piping and instrumentation diagram that includes information such as pipe numbers (diameter, material, etc.), equipment numbers (model), as well as requirements regarding pipe design and the installation of instruments based on the process requirements. A P&ID is primarily a product resulting from the collaboration between the process and instrumentation disciplines; it includes detailed process flows (such as start-up and shutdown procedures, pipeline systems for handling accidents, etc.), as well as detailed instrumentation control plans and interlock schemes.