Sandvik’s new diamond enhanced (DE) carbide range of drill bits offer far superior wear and abrasion resistant characteristics in difficult mining conditions, according to Richard Reed, Sandvik’s global RC aftermarket product line manager.
Reed said the wear and abrasion resistant properties of DE carbide bits have resulted in increases in bit life by a factor of three to five times, greatly reducing the need for multiple bit changes when drilling deep holes in abrasive formations.
The new bits have been successfully trialled in a range of drilling applications around Australia, including DTH (down the hole), TH (top hammer) and RC (reverse circulation) drilling.
“Sandvik’s DE carbide bits use a poly-crystalline diamond structure to achieve unprecedented levels of hardness and abrasion resistance,” Reed said. {{image2-A:R-w:250}}
“For example, when using standard carbides, in a typical 400m deep hole for exploration drilling, depending on abrasiveness and ground conditions, up to 20 bit changes can be required. However, using Sandvik DE carbide bits, the great majority of those bit changes are eliminated.”
In trialling its new bits, Sandvik carried out many months of testing in various ground conditions around Australia, including banded ironstone formation with layers of magnetite and quartz, where bit changes were sometimes required every six metres.
“We knew that if we could develop a bit and get it to work in these conditions, it would work anywhere,” Reed said.
“Frequently with deep and abrasive drill hole conditions, less than 50 per cent – and sometimes less than 25 per cent – of a shift can be spent actually drilling. With the use of Sandvik’s DE carbide bits, drill time can be increased to over 80 per cent of a shift.”
Particularly suitable for abrasive ground conditions and deep holes, Reed said the main benefits of the DE carbide bits included:
- Eliminating the need to sharpen bits.
- Increasing bit life by a factor of three to five times.
- At least a two to three times increase in productivity, depending on ground conditions.
- The potential to reduce hole costs by more than $10,000 per hole.
- Reduced wear and tear on the drill rig.
- Improved safety through no bit sharpening and fewer rod pulls required.
Source: Sandvik Mining