Pipeline Spool Production Flow Production of Pipe Spool Fabrication Download Prefabricated parts for piping systems, Pipeline Spool Production Coils are the pre-fabricated parts of a piping system. Pipes, flanges and fittings are called spools and are manufactured before they are used in the piping system. Coils are preformed to facilitate assembly using jacks, gauges and other tools to join the parts together. Coils join long pipes with flanges from the end of the long pipes so that they can be bolted together with matching flanges. These joints are embedded in concrete walls before the concrete is poured.