The standard method involves percussion drilling in which a drill is alternatively raised and dropped in the descending borehole. It is suited to the drilling of wells in any material from soft clay to the hardest rock.
[pdf] Haungshi Star Trip Machinery manufactures drilling rigs, air motors and air winches and offer explosive and financial services. We produce drilling rigs for quarrying, mining and civil construction, vane type, piston type air motors as well as air winches.
[pdf] Bospi is the Swiss manufacturer of drilling equipment and tools for applications in general construction and geothermal wells. Drilling companies in Switzerland and abroad rely on the quality of our products since more than 40 years. There are hardly two drill strings which look the same.
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