Product advantages
Preferred reference table for diamond composite drill bits
|
Rock |
Hardness category |
Soft |
Medium-soft |
Medium |
Medium-hard |
Hard |
Hard |
Hardest |
|
Drillability level |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
|
Praetz hardness | F≤10
| 10 < F≤15 | 15 < F≤20 |
|
Representative rocks |
Sandstone, limestone, marble, dolomite, pyrite, weak granite, shale |
Granite, strong sandstone, conglomerate, limestone, quartz veins |
Strong granite, quartzite, basalt, igneous rock |
|
PDC core drill bits |
Ordinary type |
|
|
♦ |
♦ |
♦ |
♦ |
♦ | ♦
| ♦
|
|
|
|
| Reinforced type
|
|
|
♦ |
♦ |
♦ |
♦ |
♦ |
♦ | ♦
| ♦
|
|
|
|
High-strength type |
|
|
♦ |
♦ |
♦ |
♦ |
♦ |
♦ | ♦
| ♦
| ♦
| ♦ |
