PROJECTILE FOR WELL BORING Russian patent published in 2008 - IPC E21B4/14 E21B10/36 

FIELD: mining.

SUBSTANCE: invention refers to immersed devices for well boring by rotary-percussion drilling method and can be implemented in mining, prospecting and hydro-geology. The projectile includes a percussion mechanism and a drilling tool with a central sludge catcher channel and a head part, equipped with pin rock destructing insertions, interacting with a destructed bottom hole. The said insertions are arranged along Archimedian spirals in the direction opposite to rotation of the projectile with a radial set-off of a=0.04÷0.05 m/rad from periphery to the center of the head part of the drilling tool.

EFFECT: upgraded accuracy of testing due to more complete collecting of destruction products from all bottom hole of well and evacuation of these via sludge catcher channel for sampling and increased representative characteristic of sample.

3 dwg