Patent ID: 7100622

Claim:
A scarifier for scarifying an interior wall of a sewer pipe, comprising: (a) an elongated frame having spaced apart upstanding frame elements at either end and including a set of wheels mounted on either end of said elongated frame, moveable from an extended position in which said elongated frame is raised from a support surface by said wheels to a retracted position in which said elongated frame rests on said support surface; (b) a first track extending from a first one of said frame elements to a second one of said frame elements reversibly moveable along a path defined by said frame elements in response to a control signal which controls a drive system coupled to said track; and (c) a nozzle assembly reversibly moveable along said track so that a nozzle, mounted on said nozzle assembly, which emits a jet of fluid towards an interior surface of said sewer pipe, is operative to scarify a swath along said interior surface.