DIN 20353:2016-03

In underground coal mining drilling operations are carried out on a large scale every day, primarily for blasting and anchor hole drilling, and in recent years these operations have become increasingly important for the productivity of mining operations. For the economic operation of mines it is of decisive importance that the cavities artificially created at great depths with the aid of blasting technology are safely controllable, sufficiently dimensioned and created and maintained with the lowest possible rehabilitation and cost expenditure. The anchor technology used for this purpose and heading with blasting work are based on precise, fast and cost-effective drilling work, and only they make sense. This standard applies to trapezoidal threaded connections for percussive drilling technology in mining and special geotechnical work. In percussive drilling the transfer of percussive energy from the hammer in a threaded connection usually takes place via the face of the bolted parts. The size of the contact surfaces must correspond to the impact forces to be transmitted and the load-bearing thread flanks have to transmit the applied torque in such a way that the specific surface pressure does not exceed the existing material characteristics of the components. Due to the operating conditions, a minimum backlash is necessary (dirt thread). The standard has been prepared by Working Committee NA 008-04-01 AA "Gesteinsbohren/Gezähe" ("Rock drilling/Tools") at DIN Standards Committee Mining (FABERG).