DTH technique was used in well drilling exclusively to dig, accurate, vertical bores, and rotary drilling was used to turn the hole. The Directional DTH system, patented by Atlas Copco, was first used.
[pdf] Water bore drilling relies heavily on water well rigs as they are the main equipment used for this purpose. These specialized rigs are tailored to reach deep into the earth’s surface, enabling access to underground water sources.
[pdf] Crawler and truck mounted hydraulic drilling rigs with a pull up capacity ranging from 10 to 30 tonnes, designed and optimized for the construction of water and geothermal wells with the use of double head drilling systems.
[pdf] 
