Abstract: Apparatus for cleaning the interior of a pipe while the pipe is carrying a fluid under pressure includes a ball launcher which is operable to remove a ball from a magazine and locate the ball in the flow path of the conduit to be cleaned without blockage for locking of the ball launching device; a ball receiver is located at a distance from the launcher to positively stop and remove both the debris removed from the conduit by the cleaning ball and to remove the ball from the flow line automatically and dispose it in a storage container for subsequent retrieval.