ROLLER FOR SUPPORTS OF ROLLER-CUTTER BITS Russian patent published in 1998 - IPC

FIELD: bore-hole drilling machinery and equipment. SUBSTANCE: this relates to rock crushing tools. Roller for supports of roller-cutter bits has cylindrical side surface and end surfaces which all are faced with wear-resistant and antifriction coatings such as copper-type, boron-type. Surface of coating in middle part of cylindrical surface of roller is equal to (1/2-4/5) l, and at ends of roller over circular or hollow surfaces it is equal to (1/2-1) d, where l = length of roller, mm; d - diameter of roller, mm. EFFECT: higher efficiency. 3 dwg