Re-rounding We use a portable winch system, which is compact and can be used in small areas. The basic process is winching a re-rounding tool through the defective drainpipe. A brush is then winched through the pipe to clean away any debris. A CCTV survey is then carried out to determine if the pipe has been re-rounded satisfactorily. The re-rounded pipes will then have to be relined within 24 hours. Pitch fibre pipes with up to 60% deformity and clay pipes that are displaced up to 40% can be re-rounded.