Plant & Equipment

Drilling through the lavascape

Over many aeons, volcanoes erupted from the floor of the Pacific Ocean and formed what is now known as the Hawaiian Islands. Today, those mountains of volcanic rock are providing a windfall for Blasting Technology, a US rock demolition company that is hard at work on each of the major islands in the archipelago. It currently operates a fleet of seven Sandvik Construction surface top hammer drill rigs, tapping into the islands’ solidified lava.

Blasting Technology began operations in 1987. The business has progressed from using small machines to employing cab drill units, with Blasting Technology drills now working on “The Big Island” (Hawaii), Maui and O’Ahu, plus the rocky soils of a Pacific neighbour, Guam, and in the US coastal states of Oregon and Alaska.

The company, which began working on the islands with Tamrock drills and Sandvik bits, has now switched exclusively to Sandvik products, with the backbone of its equipment fleet being the versatile Sandvik DX800 drill, with four such units having operated on construction sites and in quarries.

This drill rig has a record of reliably and productively puncturing the island rock, leaving behind smooth and vertical 114mm holes for blasters.

Now, Blasting Technology is quarrying rock with the latest generation of Sandvik DP1500i drill rigs, with the company manager extolling its attributes. “Accountants must love this machine,” Blasting Technology foreman Chris Haynes said. “I can’t imagine how anyone would not want to use these machines, just for the fuel savings.”

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The DP1500i uses 19 litres an hour less fuel than the previous DP1500 model, which – as Blasting Technology general manager Ted Fritzen has observed – means if the DP1500i ran for 40 hours a week for a year, the fuel savings would offset half the cost of the machine.

These savings are not theoretical. Fritzen reached his conclusion after fuelling and monitoring DP1500 and DP1500i drills working side by side.

Lower fuel usage has the flow-on effect of creating less air pollution. In fact, Sandvik engineers say the DP1500i’s fuel efficiency results in 35 tonnes less carbon dioxide at 2500 engine hours than is produced by its predecessor.

The drill rig also boasts a patented dust-binding system that contains the worst of the airborne refuse thrown up by a penetrating drill bit. So all in all, the machine is friendly to the environment, which is an important consideration anywhere, but a necessity on projects in Hawaii.

The DP1500i is a 24-tonne, self-propelled and tracked top hammer rock drill rig standing 3.2m high at the cab, with a lower centre of gravity than earlier models, which provides a rig greater stability while operating.

The rig carries a pivoting, telescopic boom, with the working end able to drill holes 88-152mm in diameter, as well as being fitted with a high frequency drifter that boosts the rate of penetration. The DP1500i is powered by an interim Tier 4 Caterpillar engine, whose fuel efficiency stems from smart electronic control of engine speed and air compressor and oil cooler fan operations.

PRACTICAL INTELLIGENCE

The heritage of the Sandvik DPi series can be traced back to the respected Tamrock Pantera family of drills, but the new rig certainly is not a “hand-me-down”.

Rather, it is a comprehensive package of advanced features, developed over the past decade by engineers who continually stretched and refined the parameters for efficient top hammer drilling of 88-152mm holes.

What they created was a machine with exemplary daily performance, paired with such practical improvements as a larger fuel tank capable of holding up to 681 litres, so refuelling need not occur every shift.

Additional benefits are derived from new features on the Sandvik tools used on the DP1500i – benefits that are not lost on Blasting Technology’s general manager.

“I really like the new Sandvik GT60 tube steels. It helps to keep the holes straight,” Fritzen said, comparing the GT60 87mm tube to the 60mm rod on the DP1500.

“I like the GT60 shoulder drive component and the way the shank lines up. You get a better transfer of the drill’s energy to the bit and into the rock.

“That’s another reason why the machine is drilling faster and more efficiently. It’s a great performer.”

Fritzen described the DP1500i as “20 per cent more productive right off the bat, compared with the older model. With the move up in bit diameter to 114mm and 127mm, we were able to maintain the footage and spread the pattern of drilled holes, which also reduces the drilling costs per produced tonne. We’re very pleased with that.”

The new generation of button drill bits is a factor in increased production. However, it is the machine’s software that plays a crucial role in its enhanced function, with the “i” in the model number standing for “intelligence”.

Sandvik engineers credit the machine with “practical intelligence”, ie the system can tell the operator vital information such as the condition of a hole being reamed from the rock, parts and systems that need servicing and the number of hours the drifter has been operating.

When something fails on the computer-controlled rig, a self-diagnostic system can determine what part or circuit is experiencing the problem.

“Trouble-shooting is much easier,” said Chris Haynes, whose job is to keep rigs out of trouble and to fix them when trouble
does arise.

“You get all the error messages on the screen in the cabin and they tell you where to look. The drill rig is laid out better than the older model to do trouble-shooting – the way the hoses are routed, the gull-wing service doors, the way the components are installed. If the computer finds an error, it tells you exactly where to look.”

The DP1500i also has a new air control circuit, which increases the efficiency of the compressor, a significant upgrade. As Fritzen said: “The DP1500i has plenty of air and power.”

PROMOTING SAFETY

A machine’s efficiency is not divorced from an operator’s efficiency, and the DPi series has not neglected to provide a safe and comfortable workspace for the operator.

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The pressurised and insulated cabin has an air filtration system, plus an optimum sized air conditioning unit, so the person at the controls is not distracted by discomfort.

Bright and clear monitoring screens, armrest-integrated joysticks and a nimble drilling control system give the operator firm control of their work, with the cab’s glass front providing high visibility and a high tensile steel grille protecting it against flying rock.

“The visibility is a little better; the windows are bigger and there are more of them,” Haynes said, adding that his drill operator “loves the new features, the improvements made on the machines. They [Sandvik] put the fuel tank and water tank inside the carrier so the tip factor is way reduced. I know Pete [Peterson, the operator] likes that because he is the guy operating the machine.”

DPi series drills are quite simply a good fit with Blasting Technology, a company that is planning to expand its operations.
The new models’ greater efficiency means the company can keep its current work crew of fewer than a dozen people and still take on more projects, because of the 20 per cent jump in drilling productivity.

The equipment yard at Blasting Technology has been entirely stocked with Sandvik inventory for nearly 20 years. In that time, the company has enjoyed its working relationship with Sandvik sales and service personnel on the US mainland.

“Even though our rep is on the mainland the service is great,” Fritzen said. “Even though we are far away, the parts department is great.

“Our access to ‘At Your Service’ has greatly enhanced the parts ordering process. The performance is pretty impressive and customer satisfaction is high.”

The DP1500i is the largest of the three top hammer drills in the series, the other two being the DP900i and DP1100i. All three will drill holes at least 127mm in diameter, with the DP1500i capable of 152mm. The machines are available through Sandvik Construction’s Australian operations.

 

DP1500i impresses in Russia

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While the DP1500i has impressed a US demolition company in Hawaii, the rig has also been put through rigorous testing in Russia’s west, specifically at a sandstone quarry in the Rostov region, 202km north-east of Moscow.

Sandvik Construction Russia, in conjunction with its local distributor Quarry Service, recently deployed the DP1500i at the Fedorovskoye sandstone quarry in a series of benchmark drilling demonstrations to measure the drill rig’s performance on highly abrasive sandstone.

The quarry is owned and operated by a local company, Donskoy Kamen, while a subcontractor, Yugvzrivprom, performs the necessary blasting work. 

DIFFICULT, VALUABLE MATERIAL

Although Donskoy Kamen was already familiar with the performance of the DP1500i through a highly successful demonstration on granite, the company had been experiencing problems with its existing fleet of drill rigs on the quarry’s sandstone deposit.

The sandstone’s abrasiveness places greater demands on the rock tools and uses more rig power, resulting in excessive use of fuel. Sandvik Construction and Quarry Service were asked to undertake a series of drilling tests to further demonstrate the efficiency and productivity of the drilling equipment.

While material at the Fedorovskoye quarry is the cause of problems experienced during drilling, it is also a highly valuable commodity.

The quarried rock is used as M1000 and M1200 aggregates, and is particularly sought after as it provides frost resistance up to temperatures of 150oC. Additionally, as the sandstone aggregate is of such high quality, it allows construction companies to use sandstone instead of granite in many applications, with the material becoming especially popular with road construction companies in central and southern Russia.

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DOUBLE THE PERFORMANCE

When the drilling tests began, the DP1500i was equipped with 102mm bits, and after 20 hours of intensive operation drilled a total distance of 822m.

This meant the rig had doubled the performance Donskoy Kamen had previously experienced. Next the drilling was performed with 127mm bits, with again the DP1500i displaying a remarkable penetration rate of 1-1.1 m/min.

Finally, Quarry Service engineers installed 140mm drill bits, and with this configuration the rig achieved a penetration rate of 0.7-0.8 m/min.

The drilling specialists and quarry operators saw first-hand that the DP1500i can deliver exceptional performance using any of the Sandvik tools, whatever the diameter of hole drilled.

It was not only drilling performance that impressed the client, but also the efficiency of the DP1500i configurations.

With a standard drill rig that delivers less power than the DP1500i, the bits have to be replaced every 300m to 350m (or 25 to 30 holes). If high quality rock tools are used then the bits may last 30 to 40 per cent longer.

However, as the combination of Sandvik drill rig and rock tools showed, even more impressive levels can be experienced if the right rig is used in conjunction with a powerful top hammer. In the case of sandstone drilled at the Fedorovskoye quarry, the 33kW delivered by the Sandvik DP1500i was enough to extend the service life of bits by up to 2.5 times.

Senior managers from both Donskoy Kamen and Yugvzrivprom supervised the demonstration of the DP1500i at the Fedorovskoye quarry.

They noted their current drill rigs were unable to match the DP1500i’s penetration rate due to the excessive friction of the bit, which limited drilling performance and resulted in higher fuel consumption and increased service costs.

In effect, the demonstration clearly showed the DP1500i can drill twice the distance and use half the fuel, with the drilling bits lasting 2.5 times longer.

 

Source: Sandvik Construction

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