| 摘要 |
<p>A steel-bodied bit (60) has forward canted blades (64-68) that are machined from mating planar surfaces to simplify the machining process. The edges of the forward canted blades (64-68) form a spiral surface for mounting cutter elements (61). The forward canting makes the blades (64-68) stronger and thus permits the blades (64-68) to be thinner than non-canted blades to increase the clearance between blades, which improves the movement of cuttings past the bit. Recesses are machined into the gauge face of the blades for receiving hardfacing (71-73). The hardfacing (71-73) in the recess forms a layer that cooperates with the surrounding blade material to form a smooth transition area as the bit wears during usage.</p> |
