Different Drawings used in Piping Projects

The piping system is very crucial to any industrial plant, so it is necessary to design it with care and precision. The primary responsibility of the piping engineers is to produce technical drawings of the piping system that communicates fabrication and construction requirements more simply and explicitly. There are majorly five types of piping drawings for designing process piping. These technical drawings are created from the schematics, necessary design information, and specification of the process piping system.

Let’s dig in deeper to learn the different types of piping drawings:

• General Arrangement Drawings (GAD): Piping designers develop the general arrangement drawings and piping plans for piping systems & equipment. It indicates the location of all the primary machines in the industrial plant. The main piping items (control valves, fittings, and more) instrumentation, access ladders, and platforms are also presented in General Arrangement Drawings. Generally, pipes are indicated using a top-view in the drawings, or sometimes a side-view of the pipe rack is shown on the GA drawing. General Arrangement drawings are also produced for specific mechanical pieces of equipment. These drawings usually show the main dimensions of piping using 2D views, plan (top view), elevations (side-view) and sectional drawings including line numbers, size, specifications, the direction of flow, and more to enable piping designers to extract all necessary details for isometric or fabrication drawing preparation. However, the equipment locations are revised and updated, depending on the feasibility of the piping layout arrangement.
• Process Flow Diagrams (PFD): The process flow diagrams (PFD) is a drawing that shows relationships between the major equipment such as columns, pumps, vessels, turbines, heaters, and more. It is an unscaled drawing that defines the process of flowing fluids inside the piping system. PFD is a schematic diagram describes the state of the fluid material conveyed by the piping, specify the rates of fluid flow, list the types of equipment required for the process plant, and basic parameters like pressure and temperature. Generally, the PFD does not present minor components such as pipe sizes, types of valves, specifications, and more. Further, the information gathered from PFD is then transferred to P&ID.
• Piping and Instrumentation Diagram (P&ID): Piping and Instrumentation Diagram is a detailed form of PFD and is also known as the Process Engineering flow Scheme. It is a single line schematic diagram that includes all major equipment, piping details, instrumentation details (pressure, temperature, flow instruments, pressure safety valves, control valves, and more). P&ID is the first important document that controls the activity of all other related engineering types. Hence, P&ID serves as a master document to piping engineers consisting of the vital data for material procurement and to finalizing pipe routing.
• Plot Plan Layout (PPL): The plot plans produced by the piping designer are considered as the essential documents. PPL is a scale drawing that represents the whole site of the process plant, including all boundaries, roads, plant units, buildings, equipment layouts, and other constructions of the existing project at a defined scale. Hence, the dimensional drawing of Plot Plan Layout provides an overview of the entire plant that helps piping engineers to optimize the design to reduce the costs of selected equipments arrangement.
• Isometric Drawings: Piping isometric drawings are a standard practice that represents pipe routing with proper dimensions, including all details in-depth (piping items and equipment). Isometric drawings are detailed orthographic drawings that portray a graphical representation of the 3D structure of the piping system in a 2D format. It contains valuable information used by different project stakeholders at different stages.

Conclusion

All the drawings listed above are crucial project documents, and piping engineers must prepare it with critical thinking to reduce the amount of iterations/rework in later development phases. If you’re looking for a reliable engineering partner for piping layout design, consider hiring a company that has proven expertise in multidisciplinary solutions for complex projects.