Tag Archives: bolting

Sandvik brings new Alpha thread profile to top hammer drilling applications

Equipment maintenance, Mining equipment, , , , , , ,

Sandvik Mining and Rock Solutions is launching Sandvik Alpha™ 340 asymmetric drilling tools, a new thread concept within its top hammer drilling offering for mining and tunnelling that replaces the Sandvik Alpha 330 thread system.

The new concept delivers up to 30% longer service life and increased productivity, according to the company.

The new Sandvik Alpha 340 thread is designed for use in face drilling and bolting in mine development and tunnelling, with hole sizes ranging from 43-51 mm. It features an entirely new asymmetric thread profile and has a larger diameter on the bit end thread of the drifter rod, reducing stress levels in critical areas, according to the company. Uncoupling is also easier than in previous designs, saving both time and effort.

Perhaps the biggest potential lies in the increased service life of the drill rod: with Sandvik Alpha 340, customers can achieve up to 30% longer service life – significantly increasing productivity and reducing cost per metre advanced, Sandvik says.

Robert Grandin, Product Manager Top Hammer Underground Rock Tools at Sandvik Mining and Rock Solutions, said: “The Sandvik Alpha 330 concept has served our customers extremely well over the past 20 years, ensuring highly reliable and productive drilling. With the launch of its successor, we create a revolutionising new way of working with top hammer rock tools, thanks to its asymmetric design. This new concept will deliver both immediate and long term value for our customers.”

The new thread concept also comes with improved drill bits. Sandvik’s PowerCarbide™ grades will be more widely available in the standard assortment, and many bits get design upgrades with more gauge angles or larger buttons for increased robustness.

“The new system is the driller’s choice,” Grandin said. “It is very user friendly and provides easy uncoupling – which saves a lot of frustration for the driller – but also increases productivity, leading to better drilling results.”

The new Sandvik Alpha 340 thread concept will replace its predecessor Sandvik Alpha 330 in a phase-out process over the coming quarters.

Bolting head upgrade gives Sandvik DS300 drills new life at New Afton mine

Equipment maintenance, Mining equipment, Mining services, , , , , , , , , , , , , , , ,

A like-for-like Sandvik Bolting Head (SBH) upgrade at the New Afton mine, in British Columbia, Canada, is delivering a significant productivity boost at the New Gold-owned operation, according to Sandvik Mining and Rock Solutions.

Launched over a decade ago, New Afton’s now ageing Sandvik DS300 drill rigs are being given a new lease of life, thanks to an upgrade that sees a current generation bolting head fitted in a like-for-like replacement. Not only is maintenance more straightforward and spare parts easier to source, the new bolting head is delivering a remarkable productivity increase – of 25% – Sandvik claims. In fact, so successful has the mine’s 2021 upgrade been that New Gold has recently confirmed a second of its Sandvik DS300 drill rigs will be given the treatment.

Bolting rigs are used to stabilise hanging and side walls in underground mine applications.

“The upgraded SBH bolting head fitted to the Sandvik DS300s is the business end of the drill and features the latest RD300 series rock drill,” Francois Nell, Sandvik Mining and Rock Solutions’ Head of Rebuilds and Upgrades, says. “This makes it perfect for rock reinforcement in underground mines with small-and-medium cross sections. Different bolt type and length configurations are available, providing an extensive bolt selection, while a full bolt carousel ensures the DS300 is capable of installing up to 15 bolts, ranging from 1.6-3 m in length. Bolt types include cement grouted, resin grouted, anchor point and friction bolts.”

There are several benefits of adding new technology to ageing drills, according to Nell.

“The new SBH is already proven in the field and gives an instant performance boost, thanks to the RD314’s much improved penetration rates,” he explained. “Added to that is the convenience of being able to source readily available current parts more easily, as well as increasing mine’s parts commonality across more drills.

“Also, the new SBH doesn’t put the rest of the D300 under additional strain; in fact, due to the lighter RD314 drifter compared to the drill it replaces, machine strain is, if anything, reduced.”

The SBH upgrade itself is straightforward, coming in kit form, and can be conducted by a mine’s in-house technical teams using the instruction manual the SBH comes with, according to Sandvik. Taking at most a couple of shifts to complete, customer feedback regarding the installation process has been universally positive, the OEM says.

With several hundreds of Sandvik’s Lyon, France-built D300s still working around the world, Sandvik says it expects that this SBH upgrade will be as popular with other mines as it is at New Afton.

Epiroc makes the ‘impossible possible’ with launch of Boltec ABR

Automation, Explosives and blasting, Mining equipment, Mining safety, Mining services, Sustainable mining, , , , , , , , , , , , ,

Epiroc has taken another significant step forward in its rock reinforcement automation journey with the release of the Boltec Auto Bolt Reload (ABR).

Combining the company’s ground support nous with its mechanisation and automation knowledge has resulted in a solution able to remove operators from the front end of the bolter – where personnel are most at risk of rock falls from unsupported ground – and increase bolting productivity, especially in poor ground conditions.

With mining operations steadily going deeper as they develop existing and newly discovered orebodies, the rock stresses associated with mining these orebodies are typically increasing, too. This often results in more challenging rock conditions with fractured rock mass, rock burst and squeezing ground, requiring more regular rehabilitation work. The Boltec ABR, with improved operator safety, flexibility and productivity, is the obvious choice for such conditions, Epiroc says.

Epiroc claims the Boltec ABR is the first ever underground rock reinforcement drill rig designed in such a way that the bolt type and machine work together in synergy to deliver optimal safety, performance and quality. The machine can also be equipped with a mesh delivery system.

This synergy also leads to improved accuracy in bolt installations and a reduced need for re-bolting, according to Peter Bray, Global Product Manager, Rock Reinforcement at Epiroc’s Underground division.

“By using a Boltec ABR, you are better able to install bolts and mesh correctly with high quality, reducing the need for re-bolting, re-meshing…and rehab work in the future,” he told attendees of a webinar announcing the product launch today.

The mechanisation of the bolting process – in tandem with the use of self-drilling anchors (SDAs) and pumpable resin – should provide operations with the comfort to follow recommended bolting patterns, reducing the need for the installation of additional bolts that go above and beyond optimal industry practice.

The main design feature of the Boltec ABR is the fully mechanised bolt reloading system. The system automatically feeds bolts from a large carrier magazine – able to hold 44 bolts in 2.4-m or 3-m lengths – to the feed magazine – able to hold eight bolts – all while the operator remains safe inside the cabin. This innovation removes the need for manually reloading the feed magazine, thereby reducing the associated risk to the operator.

The fast auto reloading sequence speeds up the production cycle, with a total of 52 bolts able to be installed in a heading before manual reloading of the carrier magazine. The carrier magazine is mounted on a swing arm that lowers the magazine to ground level for easy reloading behind the machine’s front support jacks – where ground support should already be in place.

Productivity can be further boosted with the operator carrying out the reloading process when bolting is being carried out in multi-bolt auto mode, according to Bray.

The Boltec ABR opens the door to other safety and productivity-enhancing autonomous functionalities previously not compatible with underground bolting machines, according to Epiroc. Tele-remote control and the aforementioned multi-bolt auto are now available options that can provide bolting potential during shift changes or when conditions preclude having an operator physically on the machine. The machine is also available with a battery-electric driveline.

Bray said the development and integration of SDAs and pumpable resin on conventional Boltec machines have been integral to achieving this new functionality.

“If you think about our face drills and long hole production rigs, they have had automation for many years,” he said. “There hasn’t been a mechanical reason why we couldn’t automate a bolting machine; the stopping point has been the type of legacy rock bolts used.”

SDA bolts, which, according to Epiroc, offer faster bolting times and higher quality installation, are not sensitive to varying conditions and will achieve consistently fast installation. This provides easier scheduling accuracy for mine planning and forecasting.

The pumpable resin, developed to address inconsistent and unreliable bolt installations as mines go deeper and rocks become less competent under added pressure, offers fast setting times and full bolt encapsulation, ensuring speed and quality of installation, the OEM says. An added plus is the resin’s insensitivity to wet ground conditions, which can be a desirable characteristic for many deep underground operations.

“Given that it is much cleaner and easier to use than traditional cement, the pumpable resin reduces hours spent on cleaning the machine,” Bray said. “Hence, it is increasing productivity by providing more bolting time.”

Like other Boltecs in the range, the Boltec ABR comes with a boom-mounted bolting system, providing flexibility in terms of coverage and bolt installation angles, according to Bray.

“It’s very rare that you have perfect straight drive profiles in underground mining,” he said. “The boom-mounted bolting system offers the flexibility to address this.”

LKAB, along with the European Institute of Innovation & Technology, have been key partners in the development of this machine, with the prototype tested out at both the Kiruna and Malmberget mines in northern Sweden.

Kiruna suffered a significant seismic event during May 2020 where several areas underground were adversely affected, providing a good test case for the new machine.

These affected areas required rehabilitation with bolts and mesh to make them safe for production again, according to Bray – a process the iron ore miner is continuing to carry out at Kiruna with the prototype Boltec ABR unit.

“The Boltec ABR was the perfect machine for the challenge; it has proven to allow safer operation and significant productivity increases when compared to LKAB’s conventional bolting fleet,” he added.

Epiroc said that up to double productivity gains were achieved in a trial with the Boltec ABR in LKAB’s Malmberget mine when compared with the miner’s conventional bolting fleet.

Bray concluded: “This solution has made the impossible possible. We can now install bolts where it used to be extremely difficult. Giving some relief to the bottleneck that rock reinforcement had become.”