Hubless/ socketless Cast Iron Soil/ drainage Pipes has long been employed by the building industry as a reliable drainage system, widely used in sanitary Drain, Waste, and Vent, sewer drainage applications. Compared with plastic (PVC) pipes, cast iron pipe is more durable. Furthemore, cast iron pipe has excellent noise suppression and fire resistant characteristics, and can be completely recycled, it has become architects' first choice for drainage inside the building. For no- hub pipe: