Stabiliser device for rotary string of drill rods with reduced friction

摘要

The stabiliser (1) has a tubular central body (3) having means for connection (3a, 3b) to a first and a second component of the string of drill rods and at least one external contact element (4) with a wall (2a) of the borehole (2). The external element (4) for contact of the stabiliser (1) with the wall (2a) of the borehole (2) has at least one means for activation (6) of a means (7) co-operating with the wall (2a) of the borehole (2) to limit the friction between the contact element (4) and the wall (2a) of the borehole (2). The activation means can consist of inter-blade spaces (6) for acceleration of the circulation (7) of the drilling liquid or by a means for coupling in rotation of the external element (4) and the central body (3) of the stabiliser (1).