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Developments of hydraulic DTH percussion drilling systems

Webinars 23 November 2022

Down-the-hole (DTH) hammer drilling technologies have been used successfully for many years in the mining as well as oil and gas industry. There are both, air and fluid / liquid driven systems on the market. Typically, DTH hammers do use a piston moved by hydraulic power or compressed air, applying alternating loads onto the drill bit to crush the rock at the borehole bottom and thus, making a hole. Currently, most DTH hammer systems do run on air or other clean fluids, whereby the quality heavily determines the service life of the tool. As a result, fluid consumption, wellbore control and cuttings transport are more difficult compared to conventional rotary drilling technologies using any drill mud. Therefore, novel DTH hammer systems being able to run with drill mud for deep, hard rock drilling have been under development. E.g., a novel DTH type percussion mechanism working with only one single moving part developed by Fraunhofer IEG will be presented. Such type of hammers will help to make percussion drilling much more successful and economic.


Volker Wittig -

Volker Wittig

Fraunhofer IEG

Volker Wittig received Diplomas in Mechanical Engineering from Technical University in Braunschweig and South Dakota State University. Initially he worked for the drilling industry as an R&D engineer in the USA, designing drilling, sampling and logging tools for soil, rock, groundwater as well as in-situ environmental, geotechnical and LWD applications. Since 2005 he has been with the International Geothermal Centre (GZB) in Bochum, starting up and managing the department for advanced drilling applications on national and international R&D projects with MS and PhD students, including teaching drilling classes. Parallel, a drilling and service company using DTH hammer technologies for the installation of ground source heat pumps together with heat pump manufacturers was in operation for a few years.

As of 1-2020, GZB was the nucleus for the new Fraunhofer IEG institute with its headquarter in Bochum and 5 other offices across Germany, where Wittig continues to lead the division on innovative drilling technologies. His current focus is on micro size, jetting type reservoir intervention / drilling, DTH fluid / mud percussion hammers, downhole sensors and data transfer, coiled tubing drilling as well as thermal based drilling applications incl. Laser, Electro Impulse and Plasma technologies.

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