The entrance to Volvo Construction Equipment’s ConExpo-Con/Agg exhibit (F3432), through what the company has dubbed “excavator alley,” will lead to the manufacturer’s largest excavator offered in North America: the 100-ton (90-tonne) EC950F crawler excavator. The reason Volvo CE is emphasizing its excavator lineup is simple, according to Ray Gallant, VP of sales support: more than half of the units sold in construction equipment are excavators.
“We see a continuing good market in the next couple of years in North America,” said Gallant, during a pre-ConExpo press event in mid-January. “Traditionally, we’ve been strong in the small construction, compact equipment and road sectors; this [excavator] takes us into the light mining as well and expands our footprint in that part of the construction-equipment arena.”
Equipped with a 603-hp (450-kW) Volvo D16 Tier 4 Final engine delivering high torque at low rpm, the EC950F was specifically designed to provide optimal productivity when paired with the Volvo A60H articulated hauler, said Gallant. The excavator fills the 60-ton, 43.9-yd³ (33.6-m³) haul truck in just four bucket passes, with an average cycle time of 20 to 25 seconds.
Boom-and-arm options include an extended boom and arm, providing longer reach at 46 ft (14 m) but less bucket capacity, and a short boom and arm that offers a breakout force of up to 76,600 lb (341 kN) and fills a larger bucket. “This machine is on a very stable base,” Gallant said, noting that the EC950F has a wider track gauge, longer track length and a heavier counterweight than most of its competitors. The machine has an overall width of 176 inches (4467 mm).
A hybrid configuration—a short boom and long arm—allows a 9.16-yd³ (7.00-m³) bucket, while the short boom/arm enables up to a 10-yd³ (7.6-m³) bucket. For comparison, a 20-ton machine—the most popular excavator size, according to Gallant—runs about a 2-yd³ (1.5-m³) bucket.
Hydraulics have been optimized to deliver constant high pressures across each phase of the digging and lifting cycle. The hydraulic system increases pump power for fast and smooth operation, while the electro-hydraulic system controls on-demand flow and reduces internal losses in the hydraulic circuit. The EC950F also comes with a boom-swing priority valve that adjusts the priority of hydraulic flow between boom up and swing to coordinate truck-loading cycle times with working conditions.
“What we’ve done with the 950 is coordinate and prioritize with operator settings how he wants the cycle time to work,” Gallant said. “The operator can set it so it lifts very quickly but swings slowly if he’s loading from ground level, or if he’s loading on a pile and the truck is below him, he can set it so the swing is very quick because he only has to lift a little.”
Unlike other excavators in the Volvo lineup, this model does not have a boost setting, but it does have different modes the operator can select depending on the situation. An Eco Mode helps the EC950F achieve better fuel efficiency when working in light conditions, while an integrated work mode can be set to I (Idle), F (Fine), G (General) or H (Heavy). The attachment-management system can store settings for up to 20 different attachments, enabling the operator to pre-set hydraulic flow and pressure through the in-cab monitor.
The EC950F comes fitted with a rearview camera and can be equipped with Volvo Smart View, which provides 360-degree vision. Available operator-assist features include Dig Assist, powered by Volvo Co-Pilot, which lets the operator know when target depth/slope levels have been achieved and provides the bucket’s real-time load. “Eventually, this machine will have a machine control system that allows the operator to set parameters for how far he wants the bucket to swing or how high he wants it to go,” Gallant said.
A remote telematics service provides constant active machine monitoring and fleet utilization reporting. If a machine requires attention, Volvo communicates directly with the local dealer. Customers receive a report to identify areas to improve worksite efficiency, avoid unplanned downtime, and catch problems before they occur.
‘Simple’ setup for EC300E Hybrid
Volvo CE is launching hydraulic-hybrid assist for excavators, demonstrating the system at ConExpo on the 30-ton EC300E Hybrid that’s now available for order in North America. The hybrid model features the same levels of controllability and performance as the standard EC300E, including the ability to work in Eco Mode and Hybrid Mode simultaneously.
It’s a “very simple system,” Gallant said, that uses the boom-down motion to charge a 5.2-gal (20-L) hydraulic accumulator mounted just behind the boom, which then delivers energy to drive hydraulic assist motors that help power the hydraulic pump. The system relieves the torque requirement from the engine, resulting in about a 15% fuel savings in normal operating conditions and 12% less CO₂ emissions compared to the conventional machine.
“We take the energy generated by the boom-down motion and capture that hydraulically and put it back into the cylinders on the upswing, which is where you need most of the pressure and power to operate,” Gallant said. “Unlike some of the competition, we’re not generating electricity, we’re not putting it in the batteries, we’re not storing it.” Competitive systems tend to capture the swing energy of an excavator’s superstructure to electrically assist the engine.
When used in high production “dig and dump” applications, especially those within a 90° swing, the hydraulic hybrid assist has a payback period of about two years, according to Volvo CE.
The hybrid system will be offered in three midrange models within the next year, Gallant said, and the company will evaluate other applications in the coming years. “Because the system works on an up-and-down cycle, it’s not every application that you see that kind of benefit. We’ll evaluate the other models and their duty cycles as we go forward,” he said. The system currently is not available for aftermarket installation.Continue reading »