en
The bit is designed for drilling of medium-hard abrasive rock formations, e.g. hard limestone and shale, dolomite, magnesite, ferrous quartzite, diorite, quartzeous porphyry, solicited shale, fine-grained skarn, weak pegmatite, martite ore and metamorphic granite rocks, most frequently found in gold, granite and copper mines.
Recommended drilling parameters for maximum efficiency of the bit: low and medium rotation speed (60-115 RPM) and axial load from 100 to 210 kN.
Rock strength range - from 24 000 to 44 000 PSI.
| Bit diameter, mm | 250.8 |
| Bit diameter, inch | 9 ⅞ |
| Bit designation, IADC | 622Y |
| Connection thread, API | 4 ½" FH |
| Bearing type | Air-cooled, on rolling bearings |
| Formation type | For medium-hard abrasive formations |
| Rotation speed. RPM | 115-60 |
| Max. applicable load, kN | 100-210 |
| Weight, kg | 45.3 |
| Bearing/cooling type | Roller – Ball – Roller / Air cooling |
| Blow-through type | Side / center |
| Cutting structure | Tungsten carbide inserts |