DRILL BIT Russian patent published in 2009 - IPC E21B10/48 

FIELD: oil-and-gas production.

SUBSTANCE: invention relates to a rock-breaking device, more specifically drill bits and can be used when drilling expendable wells. The drill bit has a body with a diamond-containing matrix attached to its butt end, divided by flushing grooves into working sectors with varying profile in the transverse-radial section of each working sector of the drill bit, alternating along the perimetre of its working butt end. Sector matrices alternating along the perimetre of the working butt end have a rectangular shape and a rectangular trapezium shape. Rectangular trapezium shaped sectors are fitted with harder diamonds and have shorter length and greater height of the incident part of the sector than rectangular shaped sectors. Running off parts of sectors, which are rectangular trapezium shaped, lie at the same level of the working surface of rectangular shaped sectors. The optimum design of the drill bit is that for which height of the incident part of rectangular trapezium shaped sectors is 1.25-1.35 times greater than the height of rectangular shaped sectors.

EFFECT: increased drilling capacity of the drill bit with increase in mechanical drilling speed.

3 cl, 2 dwg