Piping and Instrument Diagrams (P&IDs)

electric schematicPiping and instrumentation diagrams (P&IDs) describe the process flow for chemical processes. A great deal of information can be represented in a “simple” diagram. Information about the piping is represented, including pipe size, pipe material of construction, insulation, and pipe specification. Location of valves, pumps, check valves, filters, strainers, and hoses are simply displayed for an easy-to-understand and -identify arrangement.

Instrumentation is displayed using standardized symbols and labeling representing the process-sensing and -control elements. Instrumentation includes:

Instrumentation also includes process control devices such as actuated valves, control valves, pressure regulators, pressure relief devices and conservation vents.

Process control can also be represented on the P&ID to simply display how the process operates. For example, a flow meter may be used to control a valve to provide a constant flow rate to a process. Interlocks can be displayed and documented on the drawing. On a single drawing the interlocks represent what triggers an automatic response and what actions are taken.

Equipment represented on the P&ID include tanks, pumps, mixers, agitators, centrifuges, totes, drums, heat exchangers, condensers, conveyors, and filters.

Creative Engineers has years of experience with the industry-accepted ISA standard for instrumentation drawings. We engineer the process before building, saving time and money for our customers. We have an in-depth understanding of the process and how to control it. We engineer-in safety and simplify maintenance where possible. Good designs allow for good estimates and accurate scheduling of new or expanded processes.

See our example of a loop diagram (PDF).
See our example of a three-line diagram (PDF).