Abstract: The device comprises a detachable sling consisting of an upper part and a lower part. The upper part carries a self-propelled trolley. The lower part of the sling is articulated by links with supporting shoes also articulated to each other by links. The shoes are arranged symmetrically with relation to the longitudinal axis of the pipeline and are moved by hydraulic cylinders, both ends of each cylinder connecting the lower part of the sling with one of the shoes by means of ball joints. Both parts of the sling are interconnected with each other by projections and slots installed, respectively, on the upper and lower parts of the sling.

Abstract: Apparatus mountable on a pipeline of pipes welded end-to-end and having a self-propelled carriage mountable on the pipeline for travelling thereon. The carriage carries annular casings made to open up and receive the pipeline when mounting the carriage thereon and operble to a closed position circumferentially of the pipeline. A rotor travels in each casing circumferentially of the pipeline as the carriage moves axially of the pipeline. Each rotor has a tool holder that has a cleaning tool with a cutting edge tangential to the pipeline for cleaning. A cam surface on the tool holder moves in advance of the cutting edge and cams the tool holder upwardly when a weld is encountered between the pipe sections so that the cleaning tool is well protected.