ta-gti-may2002.pdf

Sealing Large-Diameter Cast-Iron Pipe Joints Under Live Conditions Technology Assessment Background Several older urban areas of the United States still have large amounts of cast-iron gas distribution mains with some 47,000 miles still in service. Individual segments of these mains average between 12 and 20 feet in length and are connected to one another by a bell and spigot joint as shown in the figure. The annular space between the bell and spigot was filled with a jute packing to provide a fluid seal and finished with a lead or cement plug.