47mm Friction bolt
- -47mm Friction boltMade from high strength steel band
- -Immediate frictional Support in axial and radial
- -Simple design,cost saving,Easy for installation
- -Usually combined with domed plates, provides anchoring force for rock strata.
- -The 47mm Friction bolt undergoes very stringent tensile testing to ensure product quality.
47mm Friction bolt Functions
47mm Friction bolt is a frictional ground support system, made from a strip of high-tensile steel, is roll-formed into a C-shape featuring a longitudinal slot for engagement. Designed with one end tapered to simplify insertion into a drill hole, the opposite end is securely welded to a ring that anchors the bearing plate. When a friction bolt is inserted into drilling hole with smaller diameter, the slot partially closes and bolt diameter is compressed, which creates radical forces on rock roof surface along the whole length and firmly holds the rock.
47mm Friction bolt Mechanical Properties
| Technical Data | TRFB33 | TRFB39 | TRFB42 | TRFB47 | |
| Drill hole diameter (mm) | 30-32 | 35-38 | 38-40 | 43-45.5 | |
| Min. Yield strength (kN) | 80 | 90 | 100 | 120 | 135 |
| Min. Tensile strength (kN) | 100 | 120 | 132 | 165 | 180 |
| Typ. Tensile strength (kN) | 120 | 135 | 150 | 180 | 200 |
| Elongation (A%) | ≥20 | ≥20 | ≥20 | ≥20 | |
| Typ. Anchorage (ton/m) | 4-6 | 4-7 | 5-8 | 6-10 | |
| Bearing plate (mm) | 150X150X4 | 150X150X4 | 150X150X4.5 | 150X150X5 200X200X5 | |
47mm Friction bolt Accessories
Bearing plate,Driver,Pull collar.
47mm Friction bolt Length & Package
Length:450-3000mm as specified
Package:100pcs — 300pcs each bundle as specified
47mm Friction bolt Applications
Mines
Tunnels
Slopes
Places where need ground support
How to work
The nature of ground must be evaluated.
Choose the proper bit and drill a hole according to bolt diameter,bolt length,and drilling procedure,and length is at least 150mm longer than length of friction bolt.
Place a plate onto the friction bolt (dome against the ring,tapered end at front).
47mm Friction bolts must be installed as perpendicular to the rock surface.
Put driver dolly into bolt and drive 47mm friction bolt into the hole until the plate is firmly against the rock surface.
Do not pound on the friction bolt when plate tightly fixes on the rock surface,in order to avoid damage of friction bolt end.
Pull tests shall be performed to determine initial anchorage of the 47mm friction bolts after installation.
