Sandvik Rock Tools’ new CT top hammer tool system was launched in November 2023.
(Photo: Sandvik)
Sustainable Tooling By Design
We look at new drill tool designs, programs and initiatives
that are driving sustainability in mining
By Carly Leonida, European Editor
Rock tools can contribute to achieving this in several ways. Firstly, through speeding the development and extraction of minerals and metals resources which are critical to sustaining a growing global population and providing critical materials to deliver the energy transition – they are enabling technologies in this sense. Second, better designs allow the maximum transfer of energy from the rock drill to the string, minimizing the amount of energy required to penetrate the rock and lowering any potential emissions from power generation. And third, through the application of new materials, advanced manufacturing processes and, later, recycling programs, drill tools can help to cut the environmental and social footprint of contractors, OEMs and miners alike.
New Products,
New Capabilities
Some good examples of this integration
are the new Sandvik CT55 and
CT67 top hammer tool systems for
surface mining, and CT67 for underground
mining, which were launched
in November 2023.
The unique curved thread design used in these systems increases efficiency and reduces cost while saving fuel and simplifying automated drilling in surface bench and underground longhole applications. The result is a 15% productivity increase and a 15% reduction in fuel consumption, as faster drilling means less flushing time.
The curved thread reduces stress levels by distributing them over a larger area inside the tool. This enables the system to handle higher drilling power, meaning drillers can harness a drill rig’s full potential. “Surface drill rigs have much more power than current standard tools can handle,” said Fredrik Björk, product manager for top hammer surface tools at Sandvik. “This means the full potential of the drill rig cannot be used. Our new CT system radically increases the fatigue strength and we’ve also seen 30% longer tool life together with better hole precision in our product evaluation tests with early-adopting customers. This is a fully optimized system that includes the drill rig, the rock drill and the rock tool. The CT system also brings out the full potential of Ranger DXi and Pantera DPi rigs.”
The higher productivity of the CT systems can be reached with more aggressive settings for parameters like percussion, rotations and feed. In underground applications, the stronger geometry that comes with the curved thread design boosts tool service life by more than 30%. The curved design also makes the CT system automation-ready, since easy coupling and uncoupling in itself is an important enabler for automation; a vital technology in many underground operations.
Sandvik also completed its rotary bit offering in April 2023 with the new RR340. The single-seal roller bearing technology and optional PowerCarbide inserts ensure reliable and efficient drilling with 45% longer service life compared to standard products. More bearing hours mean fewer bit changes and an added sustainability benefit, with reduced risk exposure and environmental impact from production and shipping.
The RR340’s longevity is thanks to an abrasion resistant radial seal. Sandvik said its shape delivers extended bearing hours and greater reliability compared to conventional seals. In addition, the RR340 features a low friction bearing. This minimizes heat generation which can otherwise cause wear and reduce efficiency. “Sandvik RR340 rounds out our offering within rotary bits, ensuring that customers in all segments and applications can find the ideal choice for their operation,” said Sandra Arman, Product Manager Rotary Bits at Sandvik Mining and Rock Solutions’ Rock Tools Division. “Field tests have demonstrated significant cost savings potential. Compared to equivalent standard air bearing bits, a typical surface mine drilling 1.5 million meters per year could expect to save more than $800,000 annually with the Sandvik RR340.”
Epiroc is also targeting sustainability through greater durability and performance. In January 2023, the company launched a new range of down-the-hole (DTH) drill bits. Thanks to an optimized face design and new carbides, the bits offer up to 20% longer service life, better productivity and safety for operators. The all-new face design enables better flushing and handling of drill cuttings and boasts more buttons (in three new shapes) to increase energy efficiency during drilling. The new carbide and heat treatment processes that Epiroc uses during manufacturing provide increased face hardness, resulting in a more durable and sturdier bit with increased service life. Longer service life means fewer interruptions during drilling and less time spent lifting and changing heavy bits. Finally, Epiroc DTH drill bits reduce the customers’ footprint, as they can drill more meters with fewer bits. As a result, less energy and raw materials are used to produce bits, and transport requirements and waste are reduced.
The MultiPoint design imparts better transfer of energy for more effective rock fracturing. Button wear is reduced, and the overall bit life enhanced. In trials, button bits equipped with MultiPoint inserts lasted up to 20% longer than the standard hemispherical design, and increased penetration rates by 10%. Wear flats also appeared slower and later in the insert life than with hemispherical inserts. Testing also revealed that the MultiPoint inserts provided smoother bit rotation and advancement.
Since launching its first DTH hammer design in the 1980s, Mincon Group’s ethos of continuous improvement has seen its product range evolve and grow. The company’s technical experts work closely with drillers to get feedback from work sites, which the engineering, manufacturing, and customer support teams use for the ongoing development of new models.
Mincon brought its next-generation DTH hammer range — the MP Series — to the market in 2023. This is centered around designs that offer high-efficiency combined with class-leading penetration rates. Mincon said the energy savings these generate will help customers to reduce their drilling costs and carbon emissions. The range starts with the MP30, a 3-in.-class hammer that can be equipped with drill bits between 85 mm (3.4 in.) and 105 mm (4.2-in.), and tops out with the MP400, a 40-inch-class hammer for large-diameter drill bits between 1,000 mm (39.4 in.) and 1,524 mm (60 in.).
In August 2023, Boart Longyear launched the IMPAKT top hammer bit. The company used advanced computational modeling to identify a ‘deadpool’ at the center of traditional bit designs. This area of low/no flow results in wasted energy due to inefficient flushing. IMPAKT’s new Raceway face profile is designed to eliminate this, improving drill string energy transfer and overall drilling performance. The design has been proven to actively clear cuttings from the entire cutting face. With flushing speeds increased by 25%, an average increase in penetration of 18%.
“We were fortunate to work with a major third-party customer during development and testing,” explained Jeff Hogan, global product line manager for rock tools at Boart Longyear. “Real world trials using a range of OEM drifters demonstrated alignment with our developmental testing and validated our innovation to deliver value for our customers.” The first line of IMPAKT tools is aimed at underground long hole drilling. These bits are available with hemispherical or parabolic carbides in sizes ranging from 64 mm to 89 mm.
Circularity Programs
for Carbides
An increasing concern for manufacturers
and drillers in recent years has
been dwindling supplies of tungsten —
a key component in cemented carbides
used extensively in drill bits which accounts
for around 50% of its use globally.
Supplies are expected to run out
within 40-100 years if consumption
rates continue unabated.
To help combat this, several OEMs have introduced carbide recycling programs. For example, in March 2023, Sandvik introduced an ‘opt-out’ recycling initiative for customers of carbide drill bits — customers must now actively opt out if they do not wish to be part of the buyback program.
Historically, carbide recycling has faced several challenges. Collection of used products has been limited, while carbide extraction has been cumbersome, inefficient and involved hazardous ways of working. Additionally, the standard Zinc Recycling Process (PRZ) has not always returned the same quality of carbide performance. Sandvik Rock Tools has chosen to use two recycling processes — PRZ and chemical cleaning.
“With the recently developed chemical cleaning process, we can now recycle carbides back to basic raw materials with the same quality and properties as virgin raw materials,” the company stated in its 2022 Sustainability report. “This generates a >64% CO2 reduction and >70% energy consumption reduction compared to mining minerals needed to produce cemented carbide.”
Sandvik is also offering its customers an extraction support service which will make it easier, faster and safer to recycle dull drill bits, starting with DTH and top hammer bits and later expanding to rotary bits and raise bore cutters. The company has a new patent-pending method that will reduce emissions from transportation of bits by 93%.
In 2022, 46% of drill bits sold by Sandvik Rock Tools were returned to the company for recycling and, by 2025, the company is aiming to collect 90% of its own used bits, as well as some from other manufacturers.
Re-grinding drill bits regularly also increases their service life, while reducing waste and lowering primary manufacturing emissions and transportation requirements. Sandvik introduced its RG600 Pro grinding machine in 2021. This is a precision grinder with an efficient water recycling system and solid production capacity. It reduces water consumption by up to 97% and can increase the time efficiency by 37% for each grinding session.
US-based roller cone bit specialist, Terelion, also has a circularity program for carbides which makes it possible to recycle all cemented carbide inserts on a drill bit back to pure tungsten, which can then be used in manufacturing new cemented carbide inserts. The company said that tools made from recycled solid carbide require 70% less energy to produce which results in 40% less CO2 emissions.
A heat-based process is first used to separate the cemented carbide inserts from the steel body of the drill bit, and the inserts are then shipped to Terelion’s recycling partner. This step is an important one as it reduces shipping emissions by more than 90% compared to shipping of complete drill bits. The used carbide inserts are then sent to a process plant in Austria where they are reduced to a powder form, before being made into new tungsten carbide inserts and placed in new drill bits.
Packaging: Small Changes,
Big Difference
When it comes to sustainability, even
small changes can make a big difference.
In 2021, Finnish rock tool supplier,
Robit, ran a sustainability competition for
its personnel. One of the best ideas was
optimization of the cardboard boxes that
contain Robit’s tools.
Based on this suggestion, the company improved the design of its button bit boxes and the new model was introduced in 2022. The change significantly reduces the space needed for transportation and storage — before the change, 700 button bits could be moved on one pallet, and four pallet collars were needed to secure the boxes. With the improved design, 900 bits could be accommodated on one pallet and only three collars were required. The results are lower transport costs, fewer emissions and less packaging wasted.
As part of its environmental, social and governance (ESG) efforts, Boart Longyear has also been working on developing environmentally friendly, reusable or recyclable packaging to reduce its impact and that of its clients. During 2022, the company implemented several initiatives at its plant in Mississauga, Canada, including sourcing locally produced recycled boxes and corrugated products to support the environment and the neighboring community, and replacing the steel strapping used to package and transport its products with composite strapping. This not only provided economic advantages through reduced cost to produce and recycle, but their lighter weight also poses less of a safety risk to employees.