| 摘要 |
In one aspect, embodiments disclosed herein relate to a secondary cutting structure for use in a drilling assembly, the second cutting structure including a tubular body and a cutter block, extendable from the tubular body, the block including at least three rows of cutting elements. In another aspect, embodiments disclosed herein relate to drilling a borehole, the method including disposing a drilling tool assembly in the borehole, wherein the drilling tool assembly includes a primary cutting structure and a secondary cutting structure, and wherein the secondary cutting structure ahs a cutter block having at least three rows of cutting elements. The method also includes actuating the primary cutting structure, drilling a first portion of the borehole with the primary cutting structure, actuating the secondary cutting structure, and drilling a second portion of the borehole with both the primary and secondary cutting structures. |
