PURPOSE: To reduce the abrasion of a roller and to facilitate the pulling-out and inlay of a support frame, by clamping the support frame having rollers mounted to the front and rear parts thereof to the flight in a scraping apparatus for scraping the precipitate or the floated substance in a sewage introducing basin through an attachment seat.

CONSTITUTION: A chain 3 is revolved along the bottom part rail 6 and the upper part rail in a sewage or waste waer introducing basin in an endless state by four chain wheels and a plurality of flight 4 are attached to the chain 3 to scrape a precipitate or floated substance. An attachment seat 11 is fixed to each flight 4 by a clamp 14 and a support frame 9 is further attached to the attachment seat 11 by the clamp 12 while two resin rollers are attached to the support frame 9 in a freely rotatable manner. Because the flight 4 always holds balance in an upright state and runs without distortion, the abrasin of the roller 10 is reduced and the pulling-out and inlay of the support frame 9 can be easily performed.