The description of the water well casing DTH drilling bit.
A water well casing DTH drilling bit is a kind of air pneumatic DTH drilling bit designed to drill through the soft ground formations and protects the water well borehole wall well. The water well casing DTH drilling bit can drill a water well borehole together with the casing pipe, the special design of the cutting head will hold the casing pipe while drilling a water well borehole.
Water Well Casing DTH Drilling Bit is the most economical solution for drilling a water well in a soft ground formation. This is particularly designed for casing water hole drilling. The reamer bits will rotate out to enlarge the water hole for the casing tube to slide down behind the reamer. When reaches a certain depth, the drill pipe needs to reversely rotate and the reamer bit will retract, this allows the Water Well Casing DTH Drilling Bit to pass through the casing.
The specifications of water well casing DTH drilling bit.
| Model | Outer Dia. of Casing Tube (mm) | Inner Dia. of Casing Tube(mm) | Wall thickness of casing (mm) | Reamed Dia. (mm) | Min. Inner Dia.of Casing Shoe (mm) | Drill Pipes (mm) | Weight (kg) |
| M115 | 115 | 102 | 6.5 | 125 | 92 | 76 | 12.5 |
| M140 | 140 | 128 | 6 | 157 | 117 | 76/89 | 22 |
| M168 | 168 | 157 | 5.5 | 182 | 142 | 89 | 38 |
| M194 | 194 | 183 | 5.5 | 206 | 166 | 114 | 61.5 |
| M222 | 222 | 205 | 8.5 | 234 | 191 | 114 | 83 |
| M273 | 273 | 260 | 6.5 | 305 | 241 | 114 | 136.5 |
| M323 | 323 | 297.6 | 12.7 | 338 | 281 | 114 | 18 |