Applicables:
It is suitable for thecovering layer of loose materials on the surface of
the strata, such as soil, clay, weathered rock, sand and stone particles,
etc.
Features:
1.The drill parts are strengthened and more wear-resistant
2.The straightness of the hole is higher;
3. The operation is simple and the cost is lower than that of other concentric drills;
4. The drill system may get stuck when encountering complex rock formations.
| 1. When drilling starts, the system drives the casing shoe and tube down |
2. When drilling finished, reverse the rotation and pull the guide device out from the tube |
3. Pour in concrete or continue to next drilling |
4. Use normal bit to drill to the desired depth. |
| No. | Items | Description |
| 1 | Casing Tube | a. Threaded casing tube, left hand thread; b.Welding type casing tube |
| 2 | Drill pipe | Thread: API (REG/IF)/NC |
| 3 | Stabilizer | Thread of stabilizer is same as that of drill pipe |
| 4 | DTH Hammer | Thread type: API REG |
| 5 | Casing shoe | a. Threaded casing shoe, left hand thread; b. Welding casing shoe |
| 6 | Wing system | See the forms for specs |
| D | t | H | C | G | ||||
| Model | OD of Casing Tube (mm) |
Thickness (mm) |
Max dia. of guide device (mm) |
Reamed diameter (mm) |
Max OD of normal bit (mm) |
Qty of wings | Bit shank | Weight (kg) |
| T90 | 114 | 6.5 | 99 | 125 | 90 | 2 | DHD3.5 | 15 |
| T115 | 146 | 10 | 124 | 157 | 115 | 2 | DHD340(TH4)/SD4/QL40 | 20.3 |
| T136 | 168 | 10 | 146 | 180 | 136 | 2 | DHD350(TH5)/SD5/QL50 | 33.4 |
| T142 | 178 | 10 | 154 | 195 | 2 | DHD350(TH5)/SD5/QL50 | 38.8 | |
| T160 | 194 | 10 | 172 | 206 | 2 | DHD360(Th6)/SD6/QL60 | 46.4 | |
| T190 | 219 | 7 | 203 | 190 | 3 | DHD360(TH6)/SD6/QL60 | 69 | |
| T240 | 273 | 10 | 251 | 240 | 3 | DHD380/SD8/QL80 | 125 | |
| T280 | 325 | 10 | 302 | 180 | 3 | NUMA100/DHD380 | 180/158 |
