摘要 |
FIELD: mining.SUBSTANCE: this method consists in well drilling by rock cutter tool of well bottom tool connected with dual drill string with continuous slurry removal from well bottom and transfer of slurry by used working fluid flow under pressure via central channel of said dual drill string. This dual drill string is composed of stationary external pipe accommodating drill bar transmitting the torque and axial force to drill bit with rock cutter tool. At a time, said external pipe is fitted in said drilled well to be left therein as a casing after drilling. Dual drill string central channel is composed by drill bar channel.EFFECT: higher efficiency and reliability, lower costs, expanded applications.2 cl, 1 dwg |