| 摘要 |
Described herein is a wear indicator (100) for use in a drill bit or a core head. The wear indicator (100) comprises an elongate element that forms part of the drill bit. The elongate element has a plurality of numbers (110, 120, 130, 140, 150, 160, 170, 180) formed along its length, each number (110, 120, 130, 140, 150, 160, 170, 180) being formed as a void and corresponds to a level of wear in accordance with the IADC dull grading system. As the drill becomes worn, the wear indicator (100) wears at the same rate to reveal one of the numbers (110, 120, 130, 140, 150, 160, 170, 180). The numbers range from“1”to“8”where the number“1”illustrates the least wear and the number“8”indicates the most wear. When unworn, none of the numbers are visible. |
