DRILL BIT BEARING ASSEMBLY Russian patent published in 1996 - IPC

FIELD: well drilling, particular, rock cutting tool for drilling oil and gas wells. SUBSTANCE: small roller bearing 4 in the drill bit assembly is located behind the large roller bearing 3 at distance of 1 =(0.5-0.6)l₁, where 1 is distance between centers of large and small roller bearings, mm; l₁ is distance between centers of large roller bearing and ball bearing, mm. Outer diameters of roller bearings 3 and 4 are connected with each other by relation 1, where Dn is outer diameter of large roller bearing, mm; dn is outer diameter of small roller bearing, mm. EFFECT: higher efficiency. 1 dwg