Drilling – Bits
| Spade Type | Thread Shank Size | Drill Bit Diameter (mm) | Flushing Hole Diameter (mm) |
|---|---|---|---|
| Centre Flush | 1/2" Whiteworth | 27 | 4 |
| Centre Flush | 1/2" Whiteworth | 29 | 4 |
| Centre Flush | M 16 | 27 | 8 |
| Centre Flush | M 16 | 29 | 8 |
| Extra Flush | M 16 | 27 | 5 |
| Extra Flush | M 16 | 29 | 5 |
| Side Flush | M 14 | 26.5 | - |
| Side Flush | M 14 | 27 | - |
| Side Flush | M 14 | 28 | - |
| Side Flush | M 14 | 29 | - |
Key Features
- A general purpose and robust rotary drill bit for wet drilling. Water flushing is through the centre hole in the drill bit body for centre flush bits, through the centre hole and two side flushing grooves for flush bits, and through two side flushing grooves for side flush bits.
- Used for high thrust and impact applications.
- The spade bit uses a time proven carbide insert, has a neutral front rake and provides good wear resistance for most types of conditions.
- The drill bit body is specifically designed for clearance of rock cuttings.
- The body is made of high tensile abrasion resistant steel.
- The spade bit is often used as a "starter" bit (hole collaring) when multiple drill rods are required. Refer to DSI Underground’s "Practical Guide to Rock Bolting" highlighting installation problems associated with collaring the hole.
- Standard diameters available are 27 and 29mm. Other diameters from 26mm through to 30mm are available by negotiation.
