Fitted precision lathe in nonstop cutting of cast iron, colored metal, and its alloy and nonmetal materials; semi- precision lathe, precision lathe, small-section precision lathe in interrupted cutting, whirling of rough turn, vortex lathe, also fitted for semi-precision milling and precisionlathes with continuous surfaces; and sometimes applied to rough expanding of holes, dry lubricating and plucking of steel, colored metal and its allied wires. Also used in geological prospecting, machine and tool manufacturing,and serves as the drill bit in wind-drill and electric drills for coal digging.