... middlings production of screw conveyor, widely used in chemical industry, building materials, cereals, feed, food, metallurgy, mining, plastic, pharmaceutical and ... powder, granular and small block material, such as cement, coal, grain, fertilizer, ash, sand etc, material temperature 200 degrees ... millimeters, a total of five kinds of specifications, length from 4 meters to 70 meters, every 0.5 meters ...