A down-the-hole drill, usually called DTH Drilling Rig, is basically a mini jackhammer screwed on the bottom of a drill string. The speedy hammer activity breaks hard stone into little flakes and dust and can be dismissed evident by the air exhaust in the DTH hammer.
[pdf] A complete range of accessories for large diameter drill rigs, including kelly bars, CFA augers, drilling equipment and tools, designed to support the full spectrum of large diameter drilling methodologies in all types of soil.
[pdf] This DTH drilling rig is specifically designed for photovoltaic foundation pile holes. It is equipped with an 86kW engine and a high-efficiency desert air filter, supporting a maximum drilling diameter of 500mm.
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