Eccentric casing drilling system is today’s preferred method for drilling in difficult ground conditions, for example, where there are boulders or loose formations.EDS is the most economical solutions because its ingenious reaming wing the bit is retrievable can be used at the next hole. This is particularly design for shallow holes, as is often the case in water well drilling, geothermal wells and for shallow micro-piling work. EDS is ideal for short holes in consolidated overburden. The component of Eccentric system consists of Pilot bits, Reamer bits, Guide device and casing shoe.
When drilling, the reamer bit will rotate out to enlarge the hole which enough for the casing tube slide down behind the reamer. When reached required depth, the drill pipe will drill to the reverse direction and the reamer bit will retract, it is allowing the whole drilling system to pass through the casing.
The below size of Eccentric systems which are available, and the special design is upon customer’s requirement:
Eccentric 90, Eccentric 114, Eccentric 140, Eccentric 165, Eccentric 190 and Eccentric 240
Application
- Geothermal well drilling
- Water well drilling
- Pipe roofing(umbrella arch drilling)
- Foundation work
- Anchoring
Specifications
| 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 |
| 108 |
93-99 |
118 |
86 |
TDS79 |
76 |
| 114 |
101-103 |
127 |
91 |
R56,T38,TDS79 |
76 |
| 127 |
114-116 |
136 |
101 |
TDS79 |
76 |
| 140 |
124-127 |
152 |
117 |
TDS98 |
76 |
| 146 |
127-132 |
154 |
117 |
TDS98 |
76 |
| 168 |
149-155 |
184 |
140 |
TDS122 |
76,89 |
| 178 |
159-165 |
194 |
150 |
TDS122 |
76,89 |
| 193 |
173-180 |
206 |
166 |
TDS139 |
89,114 |
| 219 |
199-206 |
234 |
193 |
TDS139,TDS180 |
89,114 |
| 245 |
224-231 |
260 |
210 |
TDS180,TDS220 |
114 |
| 273 |
251-257 |
300 |
241 |
TDS180 |
114,127
|
Usage:
1. In not stable rock formation, the casing is necessary to follow.
2. Usually in water well drilling, for large hole boring.
3. Drilling depth is better less than 40 metres to control the hole well.
4. Match to 6" hammer and 194mm casing tube.
5. Air pressure is 20 Bar and air volumn is 500 cfm.
6. The tools is fetched out to use in the next holes.
