Travelling bridge scraper systems installed at local sewer treatment plant and potable water treatment plants. Wide is 5 to 12 meters in one bridge for one channel or one bridge for two channels. Ideal for the scrapping of heavy-duty top and bottom sludge. Forwarding speed of bridge is 0.2 to l.8m/min, variable, and reverse speed is l.8m/min, variable. Cycloid reduction drive system. Skimmer and scraper installed to scraper top and bottom sludge. Cable reel installed. According to settling tanks, on bridge for one channel or one bridge for two channels of bridge travelling scraper installed.