The resulting top-down percussion drilling gives taper-free, elongated, and crack-free holes with glossy inner walls. Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news ...

In contrast to percussion drilling, which consists of continuously dropping a heavy weight in the wellbore to chip away at the rock, rotary drilling uses a rotating drill bit to grind, cut ...

Percussion drilling equipment several diameters (1 m length: 25 mm, 30 mm, 47 mm and 52 mm; 2 m length: 22 mm, 27 mm and 47 mm) with the associated bore rods (1 m length: 22 mm, 27 mm and 32 mm; 2 m ...