A down-the-hole drill, usually called DTH by most professionals, is basically a screwed on the bottom of a . The fast hammer action breaks hard rock into small cuttings and dust that are evacuated by a fluid (air, water or ). The DTH hammer is one of the fastest ways to drill hard rock. The system is thought to have been invented independently by Stenuic. If your down-the-hole rock drill stops working, the first thing you should do is check the power supply. For electrical drills, make sure the circuit breaker hasn't tripped and the fuse isn't blown. Check all the connections to ensure they're secure.
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