Insert cut use slotting tool to make move back and forth relative to workpiece on upend direction groove of sharp movement treatment and model the cutting treatment of aperture. Insert cut working way and dig to cut similar, but slotting tool outfit is placed in slotting machine ram on lower arbor, the Kong Zhong that can extend workpiece makes vertical stroke to reciprocate, it is working journey downward, it is a return trip up. The feed that intermittence makes after installing the workpiece on slotting machine workbench to return every time in slotting tool moves. The material of slotting tool basically uses high-speed steel, inserting cut steel and cast-iron the cutting speed when is 15 ～ 25m/min commonly. To avoid the knife after the slotting tool in the return trip face and workpiece produce acuteness clash and injury already was machined the surface and lower cutting tool life, can use rod of mobile type slotting tool. Insert cut efficiency and precision not tall, reason produces middling to use milling in batch or broaching is replaced insert cut. But slotting tool is made simple, production prepares time weak point, reason is inserted cut comfortable at in sheet or keyway of the aperture inside the treatment in pre production or spline aperture, also can machine square aperture and polygonal aperture. To be illogical of aperture or shoulder of stage of be a hindrance to inside aperture keyway, insert cutting is only treatment method almost. The upend reciprocate that slotting machine uses slotting tool is inserted cut keyway and model the machine tool of aperture. Slotting machine is used at inserting to cut sheet commonly, the workpiece of pre production, average slotting machine, keyway slotting machine, dragon door slotting machine and movable type slotting machine wait for a few kinds. The ram belt of average slotting machine writes tool carrier to make fluctuation move back and forth advocate motion, can use of the circular table of workpiece on, next slide carriage are made fore-and-aft, transverse move with circumgyrate feed. The workbench of keyway slotting machine and lathe bed couplet become an organic whole, workpiece installation is on workbench. Cross the arbor that workpiece aperture extends up from lathe bed, take those who write slotting tool to make fluctuation move back and forth at the same time advocate motion, make at the same time intermittent feed moves. Its characteristic is workpiece installation gets in that way unlike average slotting machine the limitation of pillar, reason is comfortable at machining large part (be like airscrew) Kong Zhong's keyway. Graph 3 average slotting machine CNC Milling