1. Open mixing mill has concise structure. It has advantages for example simple operation, easy to disassemble when repairing. So it is widely used in rubber industrial. 2. The roller adopts chilled cast iron. It has two structure of roller: hollow and drilled, the hollow roller is inner chamber process. Surface of hollow roller can be made to smooth roller and groove roller. 3. There are three method to adjust roller nip; manual operation, motor adjust and hydraulic adjust. 4. Users can choose material turnover device according to producing require. 5. Specifications: Φ160一Φ810; open mixing mills, sheeting mill, refining mill, cracking mill, main mother can be DC motor or AC inverter motor.