The machining accuracy of roller parts mainly refers to the concentricity of the inner hole at both ends of the shell and the roller and the machining accuracy of the axial dimension of each part. If the concentricity is too poor, will cause the bearing seizure, increase resistance, reduce the service life; if the axial part size error is too large, will form a large axial gap, resulting in axial damage, lubrication and sealing; if the installation quality is not good, the deviation and bite card, increased wear, greatly reduced roller life. Roller parts manufacturing process will affect roller dynamic load, dynamic load which is the basic reason of roller shell wall thickness and shell radial mass caused by the unbalance. To ensure the roller processing and assembly quality, the key is to find a roller manufacturer with strong technical force, perfect technical equipment scientific management and good service consciousness, the manufacturer should be able to provide from design, roller selection, economic and technical analysis to the design of the complete technical service for users. Roller parts can play an important role and value in the use of idlers, can help the use and maintenance of idlers, help users play an important role in maintenance roller and value. In belt conveyor, roller conveyor belt for supporting and cargo, can play an important role and value in the transportation, and ensure the belt sag in the scope of design in the limited.