Stabilizer device for rotary string of drill rods with reduced friction

摘要

The stabilizer ( 1 ) has a tubular central body ( 3 ) having means for connection ( 3 a , 3 b) to a first and a second component of the string of drill rods and at least one external contact element ( 4 ) with a wall ( 2 a) of the borehole ( 2 ). The external element ( 4 ) for contact of the stabilizer ( 1 ) with the wall ( 2 a) of the borehole ( 2 ) has at least one means for activation ( 6 ) of a means ( 7 ) co-operating with the wall ( 2 a) of the borehole ( 2 ) to limit the friction between the contact element ( 4 ) and the wall ( 2 a) 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 stabilizer ( 1 ).