Abstract: A sealing ring for fitting between and sealing an annular space between a spigot end of a length of pipe and a bell-shaped end of another length of pipe which are slid into each other to form a pipe joint. The sealing ring comprises an annular main body having a first surface for engaging the spigot end and a second surface for engaging the bell-shaped end during the formation of the pipe joint. A thin rupturable membrane of a thickness less than 0.008 inches is attached to the second surface about the circumference of the annular main body defining an annular cavity. A lubricant is disposed in the annular cavity, either between the second surface and the rupturable membrane or in an encapsulated cavity formed by the membrane whereby, when the spigot end and the bell-shaped end are slid into each other to form a pipe joint, the rupturable membrane is ruptured and the lubricant is released.