Abstract: There is provided a method and apparatus for simultaneously extruding two triple-wall pipes. A first extruder is connected to a first die in order to form the inner and outer wall of a first pipe and a second extruder is connected to a second die in order to form the inner and outer walls of a second pipe. A third extruder is connected to a Y-block which splits the output from a third extruder into two channels, one leading to the first die in order to form the foam core middle wall of the first pipe and the second leading to the second die in order to form the foam core middle wall of the second pipe.