ROLLER BIT Russian patent published in 2014 - IPC E21B10/16 E21B10/18 

FIELD: mining.

SUBSTANCE: roller bit comprises legs with inclined pins shifted parallel about bit axis and cutters inclined to their generating lines and having honed or cast teeth and flushing assembly. Said flushing assembly is located in bit axis while all teeth rows feature skewed teeth. Said skewed teeth are inclined to pin axis so that total axial component of simultaneous mechanical force applied by all skewed teeth to face fluid for every bit is equal and directed from centre to periphery. Alternatively, inclination of skewed teeth working surfaces to drill bit generatrix makes 5-45 degrees. Smaller inclination corresponds to larger inclination of pin axis to drill bit axes.

EFFECT: higher drill bit efficiency and better removal of sludge.

2 cl, 2 dwg