PROCESS OF CONE DRILL ASSEMBLY Russian patent published in 2002 - IPC

FIELD: drilling equipment. SUBSTANCE: process of assembly of cone drill consists in preliminary assembly of sections comprising cones of N types (N>1) put on pins of feet and fixed by locking bearing. Then sections are interjoined by welding. Feet and cones of each type are numbered. Diametrical and linear dimensions D, d, D_c,d_c, H, h, H_c,h_c, are measured in bearings of feet and cones, they are entered into storage and foot with minimal difference of radial and linear clearances ΔR and ΔH, is first chosen per each type and number of cones employed in drill bit with the help of program developed specially. Later sections with minimal differences in ΔR and ΔH, are selected per each drill bit. D and d are diameters of larger and small radial bearings of foot; D_c, and d_c are diameters of large and small radial bearings of cone; H, h are distances from axis of ball track of foot to thrust journal and to shoulder; H_c, and h_c are distances from axis of ball track of cone to thrust bearing and to shoulder. Said approach completely prevents incidental arrangement of both individual sections and drill bits from these sections. Process of assembly with optimal difference in clearances in bearings and sections of drill bit provides practically for simultaneous contacts of working surfaces of bearings and for more uniform distribution of contact loads which substantially raises strength of bearing and drilling per drill bit. EFFECT: substantially increased strength of bearings and drilling capability per drill bit. 5 dwg