The guide head (11) which is to be pushed through the old pipe by the new pipe (26) widens out towards its rear end beyond the inner diameter of the existing pipe line. The basket (12) has at least two arms (14) to connect with the guide head. The dia. of the drilling head (28), which is rotatable inside the basket, is slightly larger than the OD of the new pipe line (26). A screw conveyor (29) adjoining the drilling head can be extended by headers and is guided in a similarly extensible screw sleeve pipe (33) which is connected to the basket (12). The front end of the guide head is placed in the existing pipe end so that the device becomes centred. As the device advances, the guide head breaks up the old pipe and the arms of the basket plough through the rubble and surrounding earth, which are then pulverised by the drilling head and discharged through the screw conveyor. USE - Breaking up old buried pipe and replacing it with new.
