If revisions of piping isometrics need to be further evaluated, the fabrication schedule can fall behind. However, many projects issue drawings earlier. Ideally, drawings should be issued after a 60 percent model review. They are typically generated from CAD software (i.e AutoCAD, SOLIDWORKS) and must address specified project requirements (pressure safety valves, process vents/drains, etc). Pipe spool drawings generally derive from 3D models and are drafted by a team of mechanical engineers. Pipe spool drawings include a list of material descriptions, pipe pieces, item numbering and pipe bending data. A typical pipe spool drawing consists of a graphical representation, bill of material, and a title block. It is their assignment to generate the drawings in several standard formats required by site managers and construction companies. Pipe spool drawings are generally a service provided by mechanical drafting teams.
