A flexible annular cartridge for joining and sealing a bell and spigot pipe joint, wherein the outer contour of the cartridge is approximately frustoellipsoidal, the cartridge composed of an annular member having outer and inner surfaces and opposite first and second ends, with a plurality of pipe gripping members positioned on the inner surface; a flexible annular gasket having outer and inner surfaces, opposite first and second ends, and a circumferentially extending sealing lip projecting inwardly from the gasket inner surface, in which the annular member first end engages the flexible annular gasket second end; and a backup ring having a hardness that exceeds the hardness of the gasket, in which the backup ring engages the gasket at the gasket first end. Methods are provided for using the cartridge, as well as pipe joint that contains the cartridge.