BORE BIT Russian patent published in 2009 - IPC E21B10/02 

FIELD: mining.

SUBSTANCE: invention refers to bore bits designed for boring fractured and alternating rocks. The bore bit consists of a case with slots in a lower part inclined to the side counter to the direction of case rotation and dividing it to sectors armoured with cutting tools; the bore bit also consists of a guiding hub located in the cavity of the case and of cutting tools protectors from chip installed in the axial channels in the front part of each sector and spring loaded in axial direction; the protectors are made in form of rods with a spherical head. The protectors of cutting tools from chip are also made as a three-stepped rod. The spring of each rod is situated on its tail step in a pressurised closed chamber. Each protector is fixed in the axial channel of the sector from falling out with a removable arresting element made in form of a threaded hub or split spring ring. Implementing the disclosed bore bit reduces probability of chip of the cutting tools at boring fractured and alternating in hardness rocks and thus increases efficiency of operation.

EFFECT: reducing probability of chip of cutting tools at boring fractured and alternating in hardness rocks and thus increasing efficiency of operation.

3 cl, 2 dwg