DOUBLE TUBE DRILLING DEVICE AND DOUBLE TUBE DRILLING METHOD AND ANCHOR MEMBER CONSTRUCTION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a double tube drilling device which can be minimized a loss of kinetic energy at the time of drilling and which can be driven by pressurized air, minimizing the physical burden on workers when transporting or installing equipment, instead of hydraulic pressure.;SOLUTION: A double tube drilling device according to this invention comprises: a drilling device main body 13 having a drilling unit 11 and a feed-driving device 12 for feed-driving the drilling unit 11 in a drilling direction; an inner tube 15 which is detachably connected to the drilling unit 11 and is rotationally driven by the drilling unit 11 and is fed and driven by the feed-driving device 12 in the drilling direction; an outer tube 16 externally fitted to the inner tube 15 and driven to feed in the drilling direction by the feed drive device 12; an enlarged diameter bit 18 connected to the inner tube 15 so as to be scalable; and a down-the-hole hammer 17 that applies an impact force to an enlarged diameter bit 18, and also the double tube drilling device is characterized that a drilling hole H is drilled so that the rotational force of the drilling unit 11 and the striking force of the down-the-hole hammer 17 do not act on the outer pipe 16.;SELECTED DRAWING: Figure 1;COPYRIGHT: (C)2019,JPO&INPIT