Down-hole drill bit is supporting the use of a down-hole hammer, and through the spline operation with the hammer, widely used in open pit mine in the mining, quarry, water works, drilling of wells , excavation of side columns supporting.It divided into: low-voltage down hole type and the high air pressure DTH drill bits. The using of DTH drill bit and the hammer has the features of drilling hole straight,fast and deep. Therefore, in recent years has been more widely used.