Abstract: The invention relates to a boring machine (10) including: a frame (12) bearing at least a first rotary milling drum, at least a first arm (40) movable with respect to the body (16); at least a first support (64) bearing the first milling drum (60), the first support (64) being connected to the lower end part (40b) of the first arm (40), an actuating device (50) to displace at least the first arm (40) with respect to the body (16). The invention is characterized by the fact that the body further includes: a translational guiding device (30) extending along the longitudinal direction, the boring machine further comprising a movable member displaceable with respect to the body along the longitudinal direction while being guided by the translational guiding device (30), the first arm (40) being mounted pivotably on the movable member (34).

Abstract: The invention relates to a drilling machine (10) including a grab frame (12) which comprises a body (16) extending along a longitudinal direction (L), a movable member (32), a first arm (34) pivotable relative to the movable member, a second arm (36) pivotable relative to the movable member (32), the second arm having a lower end part, at least one actuator device (37) connected to the body to move at least the first arm (34) relative to the body; The invention is characterized in that said drilling machine (10) includes a removable milling device (100) including a first dismountable securing device (120) for removably fixing the support (110) to the body (16), and a second dismountable securing device (150) for removably fixing the support (110) to the first arm, whereby the milling device can be easily dismounted from the frame.

Abstract: An apparatus including a bore bit comprising a bottom part having an active bottom face and a top face substantially parallel to the active face; a top part fixed to suspension cables and having a bottom face facing the top face of the bottom part; a member for limiting the maximum spacing between the two parts; a cylindrical axial bore passing through both parts; a cylindrical guide penetrating into said bore; and at least one ramp-forming recess and at least one ramp-forming extension for co-operating with said ramp-forming recess in such a manner that movement of the top part towards the bottom part is converted into rotary movement of said top part about the vertical axis, with the end of said rotary movement of the top part imparting rotary movement to the bottom part.