The machining process of the eccentric shaft includes the following steps：

Material preparation: According to product requirements, select suitable materials such as cast iron, steel, etc., and ensure that the material quality is qualified.

Forging Blank: Heat the material to an appropriate temperature, then shape the blank into a preliminary form of the eccentric shaft through forging. Subsequently, remove excess burrs and correct defects generated during the forging process.

Heat Treatment: Heat treatment of the blank to improve the machinability and mechanical properties of the material.

Turning Machining:

Rough Turning: Remove excess material to initially form the shape of the eccentric shaft.

Semi-precision Turning: Further machining to bring the eccentric shaft close to its final shape and dimensions. 

Precision Turning: Fine machining to ensure the geometric accuracy and surface roughness of the eccentric shaft meet the requirements.

Grinding Process:

External Grinding: Grind the outer cylindrical surface of the eccentric shaft to improve its geometric accuracy and surface roughness. 

Internal Grinding: Grind the inner cylindrical surface of the eccentric shaft to ensure that its geometric accuracy and surface roughness meet the standards. 

End Face Grinding: Grind the end face of the eccentric shaft to make it flat and smooth. 

Polishing: Polish the surface of the eccentric shaft using a polishing wheel to remove fine scratches and unevenness, thereby improving the surface quality. 

Inspection: Inspect the dimensions, shape, and positional accuracy of the eccentric shaft to ensure they comply with design requirements. 

Packaging and Storage: Package the qualified eccentric shafts to prevent damage during transportation and storage, and store them in a dry and well-ventilated environment. 

It should be noted that when machining eccentric shafts, appropriate machining processes and parameters should be selected based on specific product requirements and machining equipment, and strict quality control should be implemented throughout the machining process to ensure the performance and quality of the eccentric shafts.