Sandvik has launched the UNIFACE down-the-hole range of drill bits with an updated design to improve bit life and productivity.
The range, which comes after the release of the company’s top centre drill bit, is designed for enhanced flushing that gives a more even wear of the gauge. In order to achieve a consistent penetration rate, the buttons have been placed so they always hit fresh rock.
The drill bits feature a raised centre that ensures centre buttons hit the rock first, resulting in better collaring and straighter holes. They also have improved number and placement of flushing holes (depending on diameter size, either three or four), with equal distance between flushing grooves, evenly distributing air flow and reducing wear on gauge buttons.
They have no face slots to ensure the air is more evenly distributed around the bit, resulting in a more even wear. This also facilitates better clearing of cuttings in front of the bit and makes it possible to evenly place the buttons.
The evenly-placed buttons enable the UNIFACE bit to cover the entire cutting area with just 90 degree rotation. This means no double breaking of the same rock or missed breaking, enabling more even wear of the buttons and resulting in increased button life. The even load distribution on all buttons also reduces the risk of button breakage.
The UNIFACE design also provides health and safety benefits as operators spend less time changing tools.