Basic Info.
Product Description
The Self-Drilling bolt is a fully threaded hollow bar that initially serves as a drill rod, utilizing a lost bit. The thread is made to comply to ISO 10208. For use in unconsolidated ground or other difficult ground conditions.
The Characteristics of Self-drilling Anchor Bolt
- Grouting and anchoring are completed at one time. The hollow anchor bar, which is used as a drill rod also, does not need to be pulled out, and the grouting is carried out from inside to outside. The whole process is simple and the construction is convenient and fast.
- Three in one function in the construction of various surrounding rock conditions, without casing or pre-grouting and other special ways, can form anchor holes, to ensure the effect of anchorage and grouting.
- The hollow anchor bar can be cut anywhere and lengthened by the coupler, so it
can be applied to the relatively narrow construction space.
4. High-pressure grouting makes it possible to fully fill the gap and consolidate the broken rock mass. The high-strength plate and nut can transfer the stress of the deep surrounding rock to the wall rock evenly, so as to support the surrounding rock.
Advantages of self-drilling bolt
1. Suitable for all kinds of geotechnical conditions. SDA bolt has a better construction effect than those of common anchor bars, especially is used in complex geological conditions, such as easy-to-collapse geology.
2. Unlimited drilling depth. Due to the limitations of existing rock bolt materials and drilling equipment, the conventional rock bolt has a relatively shallow drilling depth, but the self-drilling rock bolt can drill deeper due to its small drilling resistance.
3. Suitable for construction in narrow spaces. The length of the single bolt can be cut or extended as required. Common specifications are 2m, 3m, 4m, and 6m.
4. Simple construction process. The self-drilling bolt can complete the drilling, grouting, and anchoring in one drilling, simplify the technological process and accelerate the construction speed.
5. It helps stabilize the hole wall. When drilling, the screw grouting machine is used to supply cement grout with a water-cement ratio of 0.4~0.5 under pressure, so that the grout can quickly fill the borehole and the rock and soil mass, and be absorbed and solidified by the hole wall to ensure the stability.
• Excellent for spiling (fore-poling)
• Bolt is drilled in and grout is pumped through the center hole with pumpable resin or cement grouts
• The couplers are designed to exceed the ultimate load of the bar by 20%. The couplers are designed to minimize the loss of drill energy
• Several drill bits are available. Most widely used is the EXX Tungsten carbide chisel bit
• Standard length is 3 m (9 ft -10 ft) - Longer lengths are available: 4 m, 6 m
• Galvanized option under ASTM A123
| R-Thread Hollow anchor Bar | ||||
| Size | Outer Dia.(mm) | Ultimate Lad(kN) | Yield Load(kN) | Weight(kg/m) |
| R25N | 25 | 200 | 150 | 2.35 |
| R32l | 32 | 210 | 160 | 2.83 |
| R32N | 32 | 280 | 230 | 3.50 |
| R32S | 32 | 360 | 280 | 4.00 |
| R32L | 32 | 210 | 160 | 2.50 |
| R32N | 32 | 280 | 230 | 2.95 |
| R32S | 32 | 360 | 280 | 3.50 |
| R32S1 | 32 | 405 | 320 | 4.00 |
| R32L1 | 32 | 250 | 190 | 2.60 |
| R32N | 32 | 280 | 230 | 2.83 |
| R38N | 38 | 500 | 400 | 5.50 |
| R38N | 38 | 500 | 400 | 4.95 |
| R38S | 38 | 500 | 450 | 5.90 |
| R51L | 51 | 580 | 450 | 6.75 |
| R51N | 51 | 800 | 630 | 9.00 |
| R51L | 51 | 550 | 450 | 6.20 |
| R51L1 | 51 | 660 | 540 | 6.75 |
| R51N | 51 | 800 | 630 | 8.20 |
| R51S | 51 | 925 | 740 | 9.25 |
| T-Thread Hollow anchor Bar | ||||
| T30L | 30 | 220 | 180 | 2.90 |
| T30N | 30 | 260 | 220 | 3.35 |
| T30S | 30 | 320 | 260 | 3.60 |
| T30S | 30 | 320 | 260 | 3.35 |
| T40N | 40 | 539 | 430 | 6.20 |
| T40S | 40 | 660 | 525 | 7.20 |
| T40N | 40 | 539 | 430 | 5.70 |
| T40S | 40 | 660 | 525 | 6.80 |
| T52N | 52 | 929 | 730 | 10.20 |
| T52N | 52 | 929 | 730 | 9.70 |
