System for scraping external surface of long tubes, especially synthetic tubes for transporting domestic gas in urban gas supply networks, involves using a scraper mounting

摘要

The scraping device (1) comprises a flexible mounting (3) having several rollers (11) and a scraping tool (4). The scraping process consists of winding the mounting around the tube (2) and fixing together the mounting ends. The mounting is then given a rotational movement around the tube in a helix so that turnings are formed and a constant thickness of material is withdrawn from the tube.