A driver bit and a ring are assembled to a complete concentric system bit which is suit for 114-1067mm diameter tube.
Advantage:
1. Enhance penetration and perpendicularity
2. Reduce torque requirements
3. Deal with straight, oblique hole and other angle holes
4. Lowest effect with environment
External dia.(mm): 125/155/188/215/238/276/293/345/375/432...1090
Casing dia.(OD*ID,mm): 114*102/139*127/168*153/194*181...1067*1041
| Outer Dia of Casing Tube(mm) |
Inner Dia of Casing Tube(mm) |
Reamed Dia(mm) |
Min Inner Dia of Casing Shoe(mm) |
Drill Pipes(mm) |
Max.Outer Dia of Normal Bit(mm) |
| 114 |
101-103 |
127 |
91 |
76 |
77 |
| 127 |
114-116 |
136 |
101 |
76 |
82 |
| 140 |
124-127 |
152 |
117 |
76 |
92 |
| 146 |
127-132 |
154 |
117 |
76 |
105 |
| 168 |
149-155 |
184 |
140 |
76 |
105 |
| 178 |
159-165 |
194 |
150 |
76.89 |
125 |
| 193 |
173-180 |
206 |
164 |
76.89 |
140 |
| 219 |
199-206 |
234 |
184 |
89.114 |
150 |
| 244 |
224-231 |
260 |
210 |
89.114 |
165 |
| 273 |
251-257 |
305 |
240 |
114 |
190 |
| 323 |
301-310 |
348 |
284 |
114.127 |
220 |
| 406 |
382-388 |
440 |
364 |
127 |
255 |
| 457 |
433-439 |
488 |
413 |
140 |
340 |
| 508 |
484-490 |
538 |
464 |
140 |
385 |
| 558 |
534-540 |
590 |
514 |
140 |
440 |
| 610 |
586-592 |
642 |
566 |
140 |
485 |
| 660 |
636-642 |
694 |
615 |
168 |
540 |
| 711 |
687-693 |
745 |
665 |
168 |
590 |
| 762 |
738-744 |
798 |
716 |
168 |
640 |
| 863 |
839-845 |
900 |
815 |
168 |
685 |