| SPECIFICATIONS | |||
| IADC | WOB(KN/mm) | RPM(r/min) | Applicable Formations |
| 417/427 | 0.3-0.9 | 150-70 | very Soft formation with low compressive strength and high drillability,such as clay,soft mudstone,shale,salt,loose sands,etc. |
| 437/447 | 0.35-0.9 | 150-70 | very Soft formation with low compressive strength and high drillability,such as clay,soft mudstone,shale,salt,loose sands,etc. |
| 515/525 | 0.35-0.9 | 180-60 | very Soft formation with low compressive strength and high drillability,such as mudstone,salt,soft limestone, sands,etc. |
| 517/527 | 0.35-1.0 | 140-50 | Soft formation with low compressive strength and high drillability,such as mudstone,salt,soft limestone,sands,etc |
| 535/545 | 0.35-1.0 | 150-60 | medium soft with harder formation, more abrasive streaks,such as hard shale,mudstone,soft limestone,etc. |
| 537/547 | 0.4-1.0 | 120-40 | medium soft with harder formation, more abrasive streaks,such as hard shale,mudstone,soft limestone,etc. |
| 617/627 | 0.45-1.1 | 90-50 | medium hard with higher compressive strength as well as thick and hard streaks,such as hard shale,sands,limestone,dolomite,etc. |
| 637 | 0.5-1.2 | 80-40 | medium hard with higher compressive strength as well as thick and hard streaks,such as hard shale,sands,limestone,dolomite,etc. |
| 737 | 0.7-1.2 | 70-40 | Hard with high abrasiveness such as hard limestone,dolomite,firm sands,etc |
| 827/837 | 0.7-1.2 | 70-40 | very hard with high abrasiveness,such as quartzite,quaruzite sand,chert,basalt,granite,etc. |
