The development of crankshaft machining has been long and the application is extensive. What is the development history of crankshaft roughing?

Before the 1970s, multiple rounds were used to machine the outer circle, rounded corners and sides and steps of the journal. However, different parts of the same part required multiple processes to complete the roughing of the journal and the connecting rod neck. Multi-tool turning has a large margin, and the side of the balance block is processed as intermittent cutting and is prone to vibration and tooling problems. The tool life is low, the defect rate is high, and the cutting efficiency is low.

In the 70s and 80s, crankshaft roughing saw CNC turning, CNC milling and CNC milling. In the late 1980s and early 1990s, the car pull and car-car pull process was developed. The process has the advantages of high precision and high efficiency. In the mid-1990s, CNC high-speed external milling was developed, which is more efficient than CNC turning, CNC internal milling and car-car pulling for the crankshaft that needs to be machined on the side of the balance block.

Due to machining accuracy and machining efficiency, turning is generally only used for spindle neck machining. Crankshaft internal milling and high-speed external milling cannot process axial undercutting grooves. When the crankshaft has axial undercutting grooves, it should be processed by the car-car pulling method. When the side of the crankshaft balancer needs to be machined, the milling process is much better than the pull-up process. The utility model has the advantages of high cutting speed, short process time, small cutting force, low temperature rise, high tool life, less tool change, high precision and good flexibility of the machine tool.