Crossover kings

The Ranger series has enjoyed consistent popularity and success since its introduction in the 1990s. However, even good must sometimes evolve to become better. “The Ranger rigs have become known as a versatile tool for a wide variety of demanding surface drilling applications,” says Jarno Viitaniemi, product manager for the Ranger DXi series at Sandvik Mining and Rock Technology, outlining the key improvements. “We wanted to respond to feedback from quarry operators and contractors by developing a new rock drill family specifically for these rigs. We also increased the coverage area and improved the fuel efficiency. The new cabin and advanced automation features serve to significantly improve the ergonomics, safety and productivity of the rig.” The new Ranger DXi series currently consists of two models, Ranger DX800i and Ranger DX900i, differing mainly in the engine output. The smaller Ranger DX800i, with a 185-kilowatt (248–horsepower) engine, is ideal for infrastructure construction and civil engineering. The larger Ranger DX900i, rated at 210 kilowatts (282 horsepower), is primarily designed for large quarries and small mines. In mining applications, development drilling is the most likely application, while production drilling is also possible to some extent. The new rock drill family makes the redesigned Ranger DXi rigs the most powerful in their size class, with up to 27 kilowatts of percussion output power in Ranger DX900i. All the rock drill alternatives can be upgraded with the CSL system option to reduce lubrication oil consumption by as much as 300 grams per hour. The new Ranger DXi rigs have an entirely new feed system based on the leaf chain design to combine the benefits of both chain feed and hydraulic feed systems. The leaf chain will not stretch over time under load, resulting in longer maintenance intervals. The new feed system also directly improves the productivity of the rig thanks to a redesigned moving retainer, which combines the collaring guide and retainer in a single actuator. This eliminates the lost drilling distance between the retainer and ground level, increasing the drilled distance by 300 millimetres.

With a conventional drill rig and a rather conservative tramming time of five minutes per relocation, this would add up to 15 relocations, in other words a total of 75 lost production minutes. With a Ranger DXi rig, the increased coverage area cuts the number of necessary relocations down to three, giving a total tramming time of only 15 minutes. This means that 60 minutes of productive drilling time can be saved in each shift. In difficult ground conditions, this can potentially increase the overall output by up to 100 metres drilled per shift. From the operator’s point of view, one of the most prominent features in the new Ranger DXi rigs is the remarkably silent iCab cabin. The noise level measured in standardized conditions, with the air conditioning fan switched to the maximum, is as low as 73.5 decibels. Even lower values are realistic in normal operating conditions. Another benefit of iCab is its size. The cabin is large enough for two people, making it possible for a trainer to sit behind the operator, which can smooth out the learning curve of new personnel.

The Ranger DXi rigs offer a broad range of advanced automation features and options. With the full hole automatics option, the entire drilling cycle can be completed without operator intervention, including hole-to-hole navigation and aligning. The full radio remote control option makes it possible to remove the operator entirely from the vicinity of the drill rig, for example if the stability of the bench is questionable. With the iTorque drilling control system, several selectable drilling recipes can be saved for varying rock conditions. Other advanced automation options include the TIM3D hole navigation system, which enables the simultaneous use of the surface model and drilling plan to more accurately adjust the operation for site-specific conditions. Wireless data transfer and data collection features are also available to effectively integrate the rig to the customer’s overall drilling and blasting processes. “All in all, the new Ranger DXi series rigs offer a superior combination of productivity and advanced health and safety benefits,” Viitaniemi says. “These are rugged but user-friendly units for today’s demanding requirements and conditions in the civil engineering, quarrying and mining industries.”