Drilling through formations with loose, unconsolidated material always comes with problems such as the bore hole caving in or collasping. How to avoid these problems? With years of field practice and research, we developed concentric casing system with ring bit for the widest applications. With efficient penetration, the system is up to casing 100meters, and can also be used for foundation piling.
Applied to over burden formation with complex topographic and geological conditions, such as gravel, fissured formation, boulder, landfill of construction etc.
Specification
D
h
H
C
G
Specification
O. D. of Casing Tube (mm)
I.D. of Casing Tube(mm)
Wall thickness of casing (mm)
Max. O.D. of pilot bit (mm)
Ring Bit O.D. (mm)
Max. O.D. of Normal Bit (mm)
Hammer Type
Weight(kg)
TOP hammer type
P76/7-39
76
62
7
57
88
39
R32
3.2
P89/8-58
89
73
8
70
100
58
T38
5.8
P114/9-84
114
94
10
92
126
84
T45
7.5
P127/10-93
127
107
10
105
142
93
T45
10
P140/10-97
140
120
10
116
161
97
T45,T51
15
DTH hammer type
P114/9-84
114
94
10
94
126
84
COP34/COP32/DHD3.5
12
P127/10-93
127
107
10
105
142
93
COP34/COP32/DHD3.5
16
P140/10-97
140
120
10
116
161
97
COP44/DHD340/M40/SD4/QL40
21
P146/10-110
146
126
10
124
165
110
22
P168/12.7-127
168
142.6
12.7
141
188
127
COP54/DHD350/M50/SD5/QL50
27
P178/12.7-131
178
152.6
12.7
150
196
131
32.5
P194/12.7-145
194
168.6
12.7
166
214
145
COP64/DHD360/M60/SD6/QL60
42.5
P219/12.7-170
219
193.6
12.7
191
243
170
58
P245/12.7-195
245
219.6
12.7
214
268
195
DHD380/COP84/SD8/QL80
78
P254/12.7-203
254
228.6
12.7
224
276
203
84.5
P273/12.7-223
273
247.6
12.7
241
305
223
100
P325/12.7-276
325
299.6
12.7
292
350
276
135
P406/12.7-350
406
380.6
12.7
377
442
350
DHD112/QL120/SD12/N120
280
P508/12.7-416
508
482.6
12.7
478
545
416
522
P560/12.7-475
560
534.6
12.7
528
595
475
NUMA180SD18/Numa180/TH18/TS18/TK18
620
P610/12.7-513551
610
584.6
12.7
558
645
513
NUMA180
710
Operation Schematic Figure
Step1: The drilling in over burden formation is finished.
Step2: Reverse rotation of the hammer and pull the pilot bit out from the hole.
Step3: Replace the pilot bit with normal bit to continue drilling down.
