Roller Application: roller against the frictional force between the roller and the tape rolling, so as to achieve the purpose of the work. Roller has good waterproof and dustproof performance, small rotational resistance, Cisu roller, and running balance, roller type, long life and other characteristics. Roller axial movement: at 500N axial load, roller manufacturer, roller axial movement is not greater than 1.2mm. Assembly and welding of roller: assembly Huan idler rollers then determines the quality, Xinxiang roller, roller manufacturing process which is the most important of a process, which determines the relative positions of the various parts of roller, roller bearing The concentricity error, roller shaft and the roller tube concentricity error, the finished roller runout parameters embodied in this procedure in.