| 摘要 |
A drill and/or core tool, in particular for oil drilling and/or coring, comprising a body (2) showing a substantially cylindrical peripheral surface (3) and a front (4), blades (5) which extend from the front (4) till over the peripheral surface (3) and which show each a leading edge (6), possibly PDC cutting elements (7) which are situated at least in a central area (15A) of the front (4) and the longitudinal axes of which are transverse to the rotation axis of the tool (1), and comprising moreover, on at least one blade (5), outside said central area (15A): PDC (7C) and/or secondary (10) cutting elements which show each a cutting edge (8), forming together the leading edge (6) of the blade (5), and the longitudinal axis of which is transverse to the rotation axis, and at least one associated cutting element (10A) which is situated behind at least one of the PDC (7C) or secondary (10) cutting elements, which shows a cross-section of the same shape, at least for its portion protruding from the blade (5), than that of the PDC (7C) or secondary (10) cutting element, and which is disposed on the same blade (5).
|
