5. reverse rotation and withdraw the pilot bit to use it for next holes.
| A | B | C | D | E | F | 
| Outer Dia. of Casing Tube | Inner Dia. of Casing Tube | Reamed Dia. | Min. Inner Dia. of Casing Shoe | Hammer Type | Drill Pipes | 
| mm | mm | mm | mm | mm | |
| 114 | 101-103 | 125 | 93 | TDS79 | 60 | 
| 140 | 124-127 | 152 | 113 | TDS98 | 76 | 
| 146 | 127-132 | 154 | 115 | TDS98 | 76 | 
| 168 | 149-155 | 184 | 138 | TDS122 | 76,89 | 
| 178 | 159-165 | 194 | 148 | TDS122 | 76,89 | 
| 193 | 173-180 | 206 | 164 | TDS139 | 114 | 
| 219 | 199-206 | 234 | 185 | TDS139,TDS180 | 114 | 
| 244 | 224-231 | 273 | 219 | TDS180 | 114 | 
Order Guide: A+B+C+D+G