Epiroc’s compact underground loader features overhauled design for productivity in small mines

The Scooptram ST4 from Epiroc has been developed in close collaboration with mining experts, resulting in a compact underground loader tailored to the needs of small drift mines. This 4-tonne loader features a Stage V engine and has already undergone field testing, demonstrating impressive results in safety, productivity, and reliability.

Enhanced producivity on the redesigned Scooptram ST4

The new powertrain system, which includes updated components such as the transmission, converter, and engine options, significantly enhances the Scooptram ST4's overall performance. It is available with both Tier 3/EU Stage IIIA and Tier 4/EU Stage V engine configurations. Notably, both engine alternatives offer 20 percent more power than the Scooptram ST2G's current engine. In addition to faster cycle times and improved efficiency, the Stage V engine meets the highest emission standards, significantly reducing particulate matter (PM) and nitrogen oxides (NOx) in mining operations, thus improving underground air quality. These environmental benefits are further amplified by the loader's compatibility with HVO100 fuel, which helps reduce the overall CO2 footprint.

Additionally, the loader demonstrates a 27 percent increase in revolutions per minute (RPM) during mucking and hydraulic operations, and a 13 percent reduction in total cycle motion time. This results in faster bucket movements and hydraulic responses, leading to better fill factors and quicker loading. The enhanced powertrain enables the Scooptram ST4 to achieve up to 45 percent faster tramming speeds on flat ground with a loaded bucket and maintain higher gears even when tramming uphill under full load, delivering a notable boost in tonnage output per cycle.

Another key upgrade is the redesigned rear frame, which improves both safety and reliability. The new layout lowers the frame by 100 mm, significantly enhancing operator visibility. High-quality components, such as a reinforced drive shaft and the optional passive Diesel Particulate Filter (pDPF) system, further increase reliability by enabling longer service intervals, reducing maintenance needs, and ensuring consistent performance in demanding underground conditions.

The Scooptram ST4 is designed for drift sizes with a minimum height of 2.8 metres and performs exceptionally well at high altitudes. Field trials conducted at a mine located 4,100 meters above sea level showed the loader delivering up to 12 percent more power compared to the previous model.

"The Scooptram ST4 builds on years of experience from its predecessor, the Scooptram ST2G, and features major upgrades, particularly in productivity. With a completely new powertrain system and redesigned rear frame, combined with our proven safety features, this compact yet powerful loader is already making a positive impact in our customers' operations, as seen in earlier field trials," says Mary Zhu, global product manager Scooptram, small segment.

"The new powertrain is the foundation of the Scooptram ST4's superior mucking capabilities. Field trials show a 26 percent increase in average traction force compared to the ST2G, along with a 19 percent improvement in mechanical breakout force," adds Mary.