Grooved pipe fittings are a widely adopted type of steel pipe connection, also called clamp connection, offering significant advantages. The design specification for automatic sprinkler systems requires system pipelines to use grooved connectors, screw thread, or flange connections; pipes with a diameter equal to or greater than 100mm within the system must use flanged or grooved co... https://www.furdfittings.com/ductile-iron-grooved-pipe-fittings/