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] The KT5C Integrated down the hole drill rig for open use is an advanced drilling device integrating the down the hole drilling system and screw air compressor system, characterized by compact structure, excellent integrity and mobility.
[pdf] The HD55 uses the same frame as its heavier-duty stable mate, the HD77, and provides the ideal balance of power, features and portability for lighter commercial applications where maximum portability and a greater depth range are needed at an affordable price.
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