Pipe replacement.

摘要

A device for inserting within an existing pipe to shatter the existing pipe and replace it with a new pipe comprises a front portion 1 and a separate rear portion 2. The rear portion 2 includes a hydraulically operated hammer which is kept in engagement with a part of the front portion 1 by means of tension applied to the rear portion 2 through cables 9, 9A. The hydraulic hammer causes the front portion 1 to vibrate relative to the rear portion 2, and this vibration causes shattering of the existing pipe, whilst the tension applied through the cables 9, 9A ensures that the device is driven through the existing pipe.