Pipe spools are sections of pipe that have been put together with fittings off-site to meet the needs of a construction project, according to the International Journal of Architecture, Engineering and Construction. Pipe spools increase the speed of construction.
Prefabricated pipe spools allow pipe assembly in the early stages of a construction project. Also, pipes are easier to connect inside a climate-controlled facility than at the construction site, and pipe assemblies can be moved around and manipulated while they are being welded together off-site. If they are assembled at the work site, manipulation is usually impossible, and welders need to move into awkward positions to complete their work.