Atlas Copco: 10 years of RCS
Almost 10 years after Atlas Copco Construction & Mining Technique introduced the computerized control technology known as the Rig Control System (RCS), the design team responsible has received Sweden’s John Munck Award for technical achievement. Gunnar Brock, Atlas Copco Group CEO, said the system had not only made the company a leader in the automation and remote control of mining and construction equipment but was also a great commercial success.

But this is not a valedictory award. Jörgen Appelgren, the Atlas Copco Rock Drills R&D manager for automation, says that the next step may well be systems for autonomous operation. The Automation Ready Vehicle (ARV) hardware could be fitted, for example, to an RCSequipped LHD or rotary drill rig without the need for a major rebuild, enabling autonomous operation. Also of interest, he says, is technology that allows automated systems to interact with humans within a working area.

The Boomer S1 D has proved a popular replacement for the previous Boomer 281 drill rig,
according to Atlas Copco.

However, possible the company’s commercially most important recently introduced underground drilling rig is the Boomer S1 D face drilling rig. With a direct hydraulically controlled drilling system that incorporates the anti-jamming Rotation Pressure Controlled Feed, this single boom rig is the replacement for the company’s highly successful Boomer 281 machine. With face coverage from 6-31 m2 it can be equipped with a COP 1638, COP 1838ME or COP 2238 rock drill. The 4WD carrier offers more ground clearance than its predecessor and a higher tramming speed with better stability. The rig can optionally be fitted with a FOPSapproved cabin that has an interior sound level below 80dB(A) instead of the standard protective roof. Maintenance has also been improved.

The Boomer S1 D made a phased entry into the market as allowed by manufacturing capacity availability, starting in the second half of last year in South America. Atlas Copco says interest has exceeded expectations and sales have subsequently been made in North America and Africa, with more machines on order, so it seems that the company has successfully married the original concept with a more advanced specification.

For surface mining, Atlas Copco has been upgrading its reverse circulation (RC) technology, on both the hammer and rig front. With the new RC 50 hammer, incorporating the reverse Quantum Leap air cycle, drillers can expect penetration rates 15% to 20% higher than similar size hammers. Whether exploring for potential sites or working in an existing mine, the RC 50 hammer assures high performance, exceptional reliability, and dependable support.

The ROC L8 rig is now available in for reverse circulation drilling, in the L825 RC and L830 RC models. These are used for efficient in-pit grade control or shallow exploration holes using a reverse circulation system. Conversion to conventional DTH drilling from RC drilling can be carried out quickly, which guarantees maximum utilization of the rig’s investment. The ROC L8 with the RC system is light, flexible and transportable, for quick and successful site-to-site operation. As a standard feature, the rig stores 118 ft (36 m) of RC drill pipe, including 98 ft (30 m) in its revolving magazine, which is usually enough for in-pit grade control through two or more benches. The feed capacity facilitates deeper RC drilling, up to 328 ft (100 m) by the insertion of additional RC pipes into the carousel while drilling. The boom and feed system makes it possible to raise the exploration holes up to 45° forward and 30° left and right without moving the rig, for finding the boundaries of the orebody in the minimum number of holes.

Raising the Roof Bolt Standard
As well as building up a strong position in the exploration drilling field Atlas Copco has also developed a successful geotechnical business, including rock and soil reinforcement technology, since the 1980s. These two segments are now combined in Atlas Copco Geotechnical Drilling and Exploration (GDE). In parallel the Underground Rock Excavation team has developed the Boltec and Cabletec ranges of drill rigs for bolt placement.

At MINExpo, some 20 years after the introduction of the Swellex bolt, GDE launched an equally or possibly even more significant innovation, the Roofex bolt. This, says Atlas Copco, is a new unique, highly advanced rock bolt designed to dissipate and control large amounts of the energy liberated by the rock mass deformation process. It makes system behavior predictable and allows the amount of support to be adjusted to the level needed to prevent an excavation from caving in. Michael Hosp, GDE’s technical manager of rock reinforcement, said, “We consider Roofex as a milestone in supporting highly stressed rock mass. Roofex has the ability to cope with both high static loads and dynamic loads such as earthquakes or rock bursts.”

The frictional system is based on a steel-steel interaction between a high quality steel bar and a patented energy absorber through which the bar travels. There is a resin mixing/stop element, two insulating protective plastic sleeves, a calibrated lock nut and a face plate. As part of the system two types of monitor bolts—external and internal—are available, which allow direct visual monitoring of rock mass movement. Atlas Copco says the Roofex bolt is produced in standard lengths typically used in mining and tunneling and the displacement capacity is pre-set to order during manufacturing. It can be used for primary or secondary support systems.

Roofex has been field tested in a static application at the Iberpotash Vilafruns mine in Spain while dynamic testing has been carried out at Iamgold’s Mine Doyon in Canada. Further installations are being undertaken the manufacturer says.

The Moxy truck range—now from Doosan InfraCore.

Located in Molde on Norway’s west coast, Moxy owns the source technology for 23- to 46-ton-class articulated dump trucks (ADTs), and has networks with 61 dealers in Europe and North America, in addition to local sales corporations and R&D centers in the U.S. and U.K. The trucks are ideal for work in mines and construction in difficult terrain, says Doosan. The well-established design concept uses independent front and rear frames, so that the bodies are able to bend to the right and the left. Driving performance in narrow spaces is excellent because the turning radius is small. The ADTs can also carry a large amount of material load.

Doosan InfraCore expects that the joint network of existing and newly acquired dealers and the expanded product lineup will enable it to expand in the market for larger excavators and wheel loaders and attract large equipment buyers with package sales. The vision is to achieve “Global Top 3” status in construction machinery by 2012. In the past eighteen months, Doosan InfraCore has taken over Yantai Yuhua Machinery Ltd., a wheel loader manufacturer in China and the Bobcat, Utility Equipment and Attachments businesses from Ingersoll Rand.

Swedish Tunneling Project Uses Grindex Pumps
Grindex, specialist in submersible pumps for tough environments, has supplied seven submersible drainage pumps for the construction of a tunnel for high voltage cables in a Stockholm housing project. Installed deep in the bedrock, the pumps will keep the Skanstull-Solberga high voltage cable tunnel dry.The pumps are 50 m below the surface and need to pump out 300 liters of water every minute while drilling takes place. Wear and tear on the pumps is considerable as the water near the drilling rig is full of abrasive drill cuttings. Tunnel blasting is scheduled for completion by April 2010 with a further year before the tunnel is fully operational.

Two models from the pump series have been installed. The pump closest to the drilling rig is a Grindex Master and Grindex’s Per-Åke Jägren said, “The pumps incorporate an entirely new design, where the abrasives in the water are kept away from the sensitive parts of the pump. Our pumps have really been put to the test in this tunnel project, and have demonstrated that they can meet everything expected of them. Our own tests show that these pumps last three times longer in hard wear and tear situations like these. What we are witnessing here confirms our own tests.”

The water is pumped up from the lowest parts of the tunnel pipe to ground level and the pumps work in stages using sediment tanks along the way. The water is pumped from the drilling rig to a pump pit, where the water is pumped to the next intermediate station, containing the system’s large sediment tank. At this point most of the remaining drill cuttings are separated from the water and the water pumped on upwards is generally clean. Water samples are taken regularly to ensure that municipal water regulations are met.

The tunneling work started in January 2007 and is scheduled for completion in April 2010 when the power company Fortum will take over and start installing the power cables. Start-up of power supply is estimated to be 2011. The main contractor is Oden and the contract amount is for SEK335 million (approximately €35 million). When completed, the tunnel will free ground for 3,000 new homes in Stockholm.

Kati Oy mounts exploration drills in its own vehicle designs for work in extreme climates.

Typically Kati provides the client with surveys undertaken with, for example, Maxibor and Deviflex tools. By using inclination and deviation surveys, the location of the drill hole in 3-D can be located extremely accurately. In addition to these surveys, water pressure tests may come in handy to show the integrity of rock. These clients, mainly in the Nordic countries, including Greenland, may be major or junior mining or exploration companies, dimension stone producers, power companies, the Geological Survey of Finland, municipalities and other public sector organizations. The company has also recently worked in the rather different environment of Morocco.

Kati builds its drill rigs in the company workshop, using environmentally friendly designs that will operate in arctic conditions but at the same time ensure the occupational health and safety of the operators. The Kati drilling cabin is enclosed and as such provides good working conditions for operators, even in tough conditions. Nearly all rigs are rubber tracked, which makes moving easier and minimizes the stress to environment. Most of them are modern Hagby (now Sandvik) models, such as the DE130. Maximum achievable hole depth is 1,500 m, although the maximum drilled to date is 1,230 m, and core diameter is between 29 mm and 80 mm. Kati also has helicopter transportable units and a rig for working underground.

The firm drills more than 100 km/year with 10 to 14 drill rigs, each with a fourperson crew, achieving per rig meter numbers that Kati believes are significantly better than those of its competitors in Scandinavia. Turnover was €9.3 million in 2007. When working at remote locations for a long period the rigs are supported by, typically, a rubber-roller service vehicle (originally built for forestry), a snowmobile and buggy, and an all-terrain van and platform van. Kati has three large trailers for moving the equipment on main roads.

SRK Opens New Sweden Office
SRK Consulting is setting up a new office in Skellefteå, northern Sweden, hub of the Skellefte Mining District. The move aims to offer exploration and mining companies active in the region local access to the services of a global mining consultancy. The recent major expansion of resources exploration and development across the Fennoscandian Shield, combined with a long-established mining industry, presents an excellent opportunity for SRK to provide services for a growing number of internationally listed juniors and established mining houses.

Senior Geologist Johan Bradley is driving the initiative having recently joined SRK from Tertiary Minerals plc, one of the companies presently active in both Sweden and Finland. SRK is in the process of recruiting personnel from all mining disciplines with a view to commencing business in the second quarter of 2009.

Robit has introduced a glass fiber casing system for overburden drilling.

The Glass Fiber Casing System has a special ring assembly design giving extra protection for the casing from different drilling forces. In a test, a glass fiber casing was drilled in the ground and pulled out over and over again but suffered merely scratches on its surface.

The system is currently available for 76.1/8 casings (outside diameter 76.1 mm, maximum casing wall thickness 8 mm). This size is commonly used in forepoling, an application for tunnel roof fortification. Typical holes in forepoling are 12 m long. In a test drilling at the Robit premises some 15 m of glass fiber casing were drilled first through a 1.5-m granite block, then through 11.5 m of the overburden, and finally two meters in to the bed rock.

SMC at 10 Years of Age
During the 10 years since Sandvik formed Sandvik Mining & Construction (SMC) as one of three business areas— the others being Sandvik Tooling and Sandvik Materials Technology—the business has gone from strength to strength. There have been a number of substantial changes, not the least being the introduction of the single brand strategy. All of the main SMC mining and tunneling product ranges—drilling equipment, mechanical cutting machines, loaders and trucks and bulk materials handling systems—have progressed, making Sandvik one of the mining industry’s major one-stop suppliers.

In 2006, the established manufacturing and sales operations were organized into four customer segments: Construction, Surface Mining (which includes crushing, screening and materials handling), Underground Hard Rock Mining and Underground Soft Rock Mining (See E&MJ, October 2007, pp. 60-62). In 2007, Sandvik added a new Exploration segment intended to compete with the likes of Atlas Copco and Boart Longyear.

Growing in Exploration
When E&MJ asked how this newest segment has progressed since it was initially built from the Hagby-Asahi operation in Sweden plus SDS and UDR in Australia, the Exploration team’s response was that progress is as per the growth plan and expectations have been exceeded. Acquired operations have been integrated into the SMC organizational structure, with common activities such as finance and R&D centralized.

The segment organization is being developed on a global basis, with staff in all the main SMC regional operations as well as at the manufacturing sites in Sweden and Australia. The structure is designed to meet the growth targets for the existing product offering as well as new offerings; to pay more attention to the aftermarket, which is already 50% of the business and growing; to find and utilize synergies between products and offerings; and to strengthen aftermarket activities in order to better support customers. In January 2008, Sandvik agreed to acquire the South African company Corstor International, which manufactures and markets borehole core storage and handling systems for mining and exploration as well as distributing analysis and survey equipment in Africa. The targets set for future growth are quite high and SMC wants to be the leading company on the exploration equipment market.

No Shortage of Challenges
Kjell Carlsson, president of the Exploration segment, summarizes progress and opportunities as follows: “All the acquired companies have outstanding competence in their special areas. What Sandvik, using the new structure, can add is total solution provider competence.

“New resources are being found in deeper and more complicated formations. Specialized exploration drilling teams are now working with hole lengths up to 3,000 meters and not only downward but horizontally too. This calls for stronger drills, more advanced diagnostics and more durable consumables. All this fits Sandvik’s new offering very well.”

Very little investment has been devoted to R&D concerning the automation of exploration drill rigs on the market in general. But, as the availability of skilled labor is in decline and safety standards become more stringent, it is inevitable that more effort will be made in this area. In future the “drillers” might be inexperienced operators, who require more information from the automatic systems on the rig because they are unable to “read” the process in the way that experienced drillers can. Equally automation will be a big help in remote locations and where very deep holes are needed to reach feasible mineral formations.

“One of the most important driving forces for development is to increase safety in every way, for the operators and the environment. But, all in all, the most important factor now and the future is still higher productivity—better samples obtained more cost-efficiently,” said Carlsson.