A pipe scraper assembly is forced through condenser pipe interiors for scraping residue off the inner wall surface. The scraper assembly is formed with a cylindrical body with a head and a tail end. Several mutually spaced apart rings are coaxially and rotatably supported on the cylindrical body between the head and the tail end. The diameter of the rings corresponds to the inner diameter of the pipe to be scraped. The rings have a radial cut formed therein which extends obliquely relative to the longitudinal axis of the cylindrical body.