Rio Tinto Group
DRILLING DEVICE COMPRISING A TUBULAR SHEATH SECURED TO AN ACTUATOR

Abstract:

Drilling device comprising an actuator comprising an actuator body and a rod bearing at its free end a drill bit, a tubular sheath secured to the actuator body and comprising walls surrounding the drill bit and a lower opening, a system for detecting contact between the drill bit and the electrolyte bath by analysis of an electric signal; the tubular sheath being secured to the actuator body by means of an electrically insulating fastener, and the rod and the drill bit being remote from the walls of the tubular sheath when the drill bit is moved with respect to at least one lower portion of the tubular sheath and below the lower opening.