On piping drawings that are issued for construction or fabrication, piping 12” and under is usually shown as a single line. This approach keeps piping designers designing pipe while training the drafters how to layout pipe.įront End Engineering Design (FEED)/ Detailed Design Some companies will be structured so a senior piping designer creates a hand drawn single line which will be given to a 3D CAD operator or drafter to be drawn up. However, with the advent of 3D piping software, this changed as the 3D operator can layout and arrange the piping in many different configurations with ease. There may be several iterations of a single line piping drawing.īefore the widespread acceptance of 3D software, a piping one line was one of the most critical steps in the design process. The designer should use the equipment location plan, site survey data, P&ID and other relevant drawings to produce an optimal piping layout. These drawings are often hand drawn and are used as a tool for the designer to begin to layout pipe on a pipe rack. These drawings are the first step in converting the information on a P&ID to what tradespeople will use to fabricate the installation. This article contains information on single line drawings as part of the layout process and in final design.

Single line drawings take less time to create and show all the information required to layout and fabricate a piping system. It is drawn to scale so the relationships of the aforementioned are correctly shown. A piping single line drawing (or piping one line drawing) is a piping drawing that shows the size and location of pipes, fittings and valves.

Orthographic piping drawing