Drilling – Bits
| Spade Type | Thread Shank Size | Drill Bit Diameter (mm) | Flushing Hole Diameter (mm) |
|---|---|---|---|
| Centre Flush | 1/2" Whiteworth | 26.5 | 4 |
| Centre Flush | 1/2" Whiteworth | 27 | 4 |
| Centre Flush | 1/2" Whiteworth | 28 | 4 |
| Centre Flush | M 16 | 27 | 8 |
| Centre Flush | M 16 | 28 | 8 |
| Extra Flush | M 16 | 26.5 | 5 |
| Extra Flush | M 16 | 27 | 5 |
| Extra Flush | M 16 | 28 | 5 |
Key Features
- A general purpose rotary drill bit for wet drilling which is suitable for medium thrust applications. Water flushing is through the centre hole in the drill bit body for centre flush bits and through centre hole and two side flush grooves for extra flush bits.
- High penetration bit for medium and soft rock.
- The large drop centre bit uses a time proven carbide insert, has a neutral front rake and provides good wear resistance.
- The drill bit body is specifically designed for clearance of rock cuttings. The bit body is made of high tensile abrasion resistant steel.
- Reference should be made to DSI Underground’s "Practical Guide to Rock Bolting".
- Highlighting installation problems associated with collaring the hole, angle bolting, hole diameter and depth.
