Chain scraper conveyor refers to scraper or plate is moved with the drag chains , to carry loosen materials inside the trough. It is composed of machine head, middle section and machine tail. Chain scraper conveyor is divided into single chain, double chain ,double centered chain and triple chains . Chain scraper conveyor can carry materials horizontally as well as incline conveying . When materials are carried upwards , the incline degree shall be less than 25 degree of the coal layers. When materials are carried downwards, the maximum degree shall be less than 20 degree . When there exist big incline degree, must set up the anti slide device. The flexible chain scraper conveyor can bend 2 degree to 4 degree from the horizontal and vertical direction.