The Self Drilling Anchor system is comprised of a hollow threaded anchor bar with a sacrificial drill bit that performs drilling, anchoring and grouting in a single operation. Self drilling anchor system is mainly used in slope stabilization, tunneling pre-support, foundations with micro piles etc projects.
Advantages and Characteristics as below:
1. No casings required, because anchor bars can be drilled into loose soils without needing casings to support the boreholes.
2. Fast drilling and installation, because drilling, installation and grouting are in a single operation.
3. Both rope threads and trapezoid threads are robust and ideal for rotary-percussive drilling and ensuring a high level of bond with the borehole gout.
4. The hollow core not only serves for flushing during drilling, but also for grouting after drilling.
5. Continuous threads ensure the bars can be cut and coupled at any point, or extended.
6. Different anchor bits are available for different ground conditions.
R thread anchor bar or called rock bolt, soil nail, which is a kind of threaded hollow bar, bar surface with an rope thread according to ISO 10208 & 1720. It was firstly invented by MAI on 1960S to solve the low construction speed on complicated underground works, nowadays; it is very popular all around the world.
Size
O.D(mm)
I.D(mm)
Ultimate Load(KN)
Yield Load(KN)
Weight(kg/M)
R25N-14
25.0
14.0
200
150
2.3
R32L-22
32.0
22.0
210
160
2.8
R32N-21
21.0
280
230
2.9
R32N-18.5
18.5
3.4
R32S-17.5
17.5
360
3.5
R32S-15
15
4.1
R38N-21
38.0
500
400
4.8
R38N-19
19.0
5.5
R51L-38
51.0
550
450
6.0
R51L-36
36.0
7.6
R51N-36
800
630
R51N-33
33.0
8.4
Steel grade
Acc. to EN10083-1
Thread direction
Left hand
Thread standard
ISO 10208 / ISO1720