CBN inserts are always used for rough and mid-finish machining hard ferrous metal, just like hard cast iron workpiece and hardened steel workpiece. The main and typical application case of Solid CBN inserts is the rough machining of large CI roll, slurry pump, industrial pump, large hardened steel workpiece and so on. The unique advantages of Solid CBN are listed as follow: can under quite considerable cutting depth, good performance at impact resistance, wearable, long service life, high production efficiency and so on.