Drill bit

Abstract

The proposed device relates to roller drill bits with air drilling capability and can be used for drilling of rocks of high hardness. The drill bit includes a body and rock-destroying elements with cutting equipment mounted on the body one inside the other by means of bearing supports, wherein the inner element is located at an angle relatively to the axis of the drill bit, and the outer element is located in the opposite direction of the axis. The device provides for an increase of the service life, high efficiency, and interchangeability due to a special design, which envisages the cutting equipment formed as replaceable jet nozzles made of hardwearing material and provided with arm insertions, preferably made of wolframite-cobalt based alloy, wherein the bearing support of each rock-destroying element is furnished with a unit adjusting the axial play value of the rock-destroying elements.

1 . A drill bit having an axis, and comprising: a body and rock-destroying elements supplied with cutting equipment, said rock-destroying elements include an inner element and an outer element mounted on the body one inside the other by means of bearing supports, said inner element is located at an angle relatively to the axis, and said outer element is located at the opposite direction of the axis;
 wherein the cutting equipment is formed as replaceable jet nozzles made of a predetermined hardwearing material and provided with arm insertions made of a predetermined firm material, wherein each said bearing support is furnished with a means for adjusting an axial play value of said rock-destroying elements.