Expandable Rock-bolts
A rock bolt is an anchor bolt for stabilizing rock excavations. They are designed for consistent support to provide safety optimum control of rock mass in mining and tunneling. The rock bolts offer high yielding and breaking load pressures while preserving good elongation properties for safety. The rock bolts support secure potentially unstable areas, and they also control dilution while boosting productivity. The rock bolts have outstanding tensile strength and elongation that provides excellent energy absorbency in challenging mining sites and fields. The expandable rock bolts have a perfect load-bearing capacity. They have a very high resistance to crack, and they have good heat-bearing features.
Properties of Expandable Rock-bolts:
- Excellent energy absorbency
- High load yielding
- Good deformity
- Non-eroding nature
ROCK REINFORCEMENT WITH EXPANDABLE ROCK BOLTS
The ERB – Expandable Rock Bolt is a full-column anchored rock bolt that forms a mechanical interlock between the borehole wall and the bolt over the entire length of the bolt. For maintaining stability and safety during the working environment, the rock surrounding underground excavations must be reinforced stabilized. This is accomplished by inflating the ERB with high liquid pressure.
When the pump is going off, the ERB does provide full rock support action. In addition, when the ERB is inflated, the fastener length contracts, successfully tensioning the faceplate against the rock surface.
As this Expandable Rock Bolt is assembled using water, there are no specific chemical hazards to be concerned about. These pure steel fasteners are allowed to stand without harming the environment.
The ERB is a low-cost method of rock reinforcement that can be used in a wide range of rock conditions, from soft to hard.
It is adaptable and will allow for variations in borehole diameter. The ERB is designed to withstand large rock movements while maintaining its high strength properties. Furthermore, the ERB is an environmentally friendly sustainable rock reinforcement solution that does not require the use of cement grout or other chemicals to anchor the bolt.
| ERB 120 | ERB 120+ | ERB 160 | ERB 160+ | ERB 240 | ERB 240+ | |
|---|---|---|---|---|---|---|
| Bolt diameter | 28 mm | 28 mm | 38 mm | 38 mm | 38 mm | 38 mm |
| Profile diameter | 27.5 mm | 27.5 mm | 36 mm | 36 mm | 36 mm | 36 mm |
| Material thickness | 2 mm | 2 mm | 2 mm | 2 mm | 3 mm | 3 mm |
| Upper bushing diameter | 28 mm | 28 mm | 38 mm | 38 mm | 38 mm | 38 mm |
| Inflation bushing diameter | 30/37 mm | 30/37 mm | 41/48 mm | 41/48 mm | 41/48 mm | 41/48 mm |
| Hole diameter | 32 – 39 mm | 32 – 39 mm | 43 – 52 mm | 43 – 52 mm | 43 – 52 mm | 43 – 52 mm |
| Minimum breaking load | 120 kN | 120 kN | 160 kN | 160 kN | 240 kN | 230 kN |
| Minimum elongation | 10 % | 20 % | 10 % | 20 % | 10 % | 20 % |
| Typical elongation | 15 % | 30 % | 15 % | 30 % | 15 % | 30 % |
| Standard length* | 1.5 – 4.0 m | 1.5 – 4.0 m | 2.4 – 6.0 m | 2.4 – 6.0 m | 2.4 – 6.0 m | 2.4 – 6.0 m |
