Epiroc (then Atlas Copco) originally introduced the Powerbit top-hammer bit for surface drilling applications in 2016.

Now, it has launched the underground version, designed to work with the higher drilling speeds of the latest drilling rigs and the strength of the newest rock drills. According to Epiroc, it can also enhance the productivity of older rigs.

While the Powerbit Underground can drill up to 15% faster than previous Epiroc models, the Swedish manufacturer claimed that it also outperformed all standard bits during global testing and offered productivity improvements.

Indeed, Johan Thenór, product line manager for Tophammer products, said the new bit averaged around 37% more drill metres before it had to be discarded, even managing 82% during one set of tests.

The tests also showed a higher penetration rate and longer intervals between regrinds, Epiroc said.

"The [flushing] hole configuration maximises flushing efficiency, which is key to the high penetration rate," explained Robert Arnoldsson, senior product specialist, Tophammer products at Epiroc

He said the bit's face is configured so that it can remove cuttings faster than before, while the steel used to make the bit is 15% harder than on previous models.

Like its surface predecessor, the Powerbit Underground comes with trapezoid-shaped buttons, or Trubbnos. According to Epiroc, these can increase penetration rate and service life when compared with conventional, semi-ballistic buttons.

"Since the bit's performance is crucial to the rig's ability to penetrate rock fast, customers can look forward to a new product that will greatly improve drilling efficiency," Thenór added.

Epiroc is first rolling out the 45mm-dimension Powerbit Underground, which will be followed by the 48mm, 51mm and other versions.