TDS overburden drilling systems are designed to use ring bit which is not connected to casing shoe.
Special profile DTH Bit passes through enough large inner diameter of ring bit.
| Model | Casing Size | Ring bit Diameter | Applicable Hammer | ||||||
| OD | ID | T | OD | ID | T | OD | OD | ||
| MM | INCH | MM | INCH | ||||||
| TDS140 | 178.0 | 158.0 | 10.0 | 7.01 | 6.22 | 0.39 | 192 | 7.56 | TG50 |
| TDS165 | 194.0 | 174.0 | 10.0 | 7.64 | 6.85 | 0.39 | 204 | 8.03 | TG60 |
| TDS190 | 219.0 | 193.6 | 12.7 | 8.62 | 7.62 | 0.50 | 231 | 9.09 | TG60 |
| TDS215 | 244.5 | 224.5 | 10.0 | 9.63 | 8.84 | 0.39 | 257 | 10.12 | TG80 |
| TDS240 | 273.0 | 241.0 | 16.0 | 10.75 | 9.49 | 0.63 | 287 | 11.30 | TG80 |
| TDS280 | 324.0 | 304.0 | 10.0 | 12.76 | 11.97 | 0.39 | 340 | 13.39 | TG100 |
| TDS315 | 356.0 | 332.0 | 12.0 | 14.02 | 13.07 | 0.47 | 370 | 14.57 | TG120 |
| TDS365 | 406.0 | 381.0 | 12.5 | 15.98 | 15.00 | 0.49 | 422 | 16.61 | TG125 |
| TDS410 | 457.0 | 417.0 | 20.0 | 17.99 | 16.42 | 0.79 | 475 | 18.70 | TG320 |
| TDS460 | 508.0 | 483.0 | 12.5 | 20.00 | 19.02 | 0.49 | 528 | 20.79 | TG370 |
| TDS560 | 610.0 | 578.0 | 16.0 | 24.02 | 22.76 | 0.63 | 632 | 24.88 | TG450 |
| TDS610 | 660.4 | 622.0 | 19.2 | 26.00 | 24.49 | 0.76 | 684 | 26.93 | TG550 |
| TDS660 | 711.2 | 681.2 | 15.0 | 28.00 | 26.82 | 0.59 | 735 | 28.94 | TG550 |
| TDS710 | 762.0 | 712.0 | 25.0 | 30.00 | 28.03 | 0.98 | 788 | 31.02 | TG550 |
| TDS760 | 813.0 | 788.0 | 12.5 | 32.01 | 31.02 | 0.49 | 835 | 32.87 | TG550 |
| TDS810 | 860.0 | 810.0 | 25.0 | 33.86 | 31.89 | 0.98 | 880 | 34.65 | TG550 |
| TDS860 | 914.4 | 882.0 | 16.2 | 36.00 | 34.72 | 0.64 | 938 | 36.93 | TG640 |
| TDS960 | 1020.0 | 988.0 | 16.0 | 40.16 | 38.90 | 0.63 | 1048 | 41.26 | TG800 |
| TDS1160 | 1200.0 | 1168.0 | 16.0 | 47.24 | 45.98 | 0.63 | 1230 | 48.43 | TG800 |
| TDS1360 | 1400.0 | 1368.0 | 16.0 | 55.12 | 53.86 | 0.63 | 1430 | 56.30 | TG900 |
| TDS1410 | 1500.0 | 1468.0 | 25.4 | 59.06 | 57.80 | 1.00 | 1530 | 60.24 | TG900 |
*Other size of TDS system is available upon customer's request.