Pioneering Electro-Hydraulic Solution Significantly Improving Fuel Efficiency in Construction Equipment

Mon December 07, 2020 - National Edition
Volvo Construction Equipment

Volvo EC300E 30 ton excavator used as a test bed.
Volvo EC300E 30 ton excavator used as a test bed.

Volvo Construction Equipment (Volvo CE) is committed to a sustainable future — achieved through internal developments and external partnerships.

As part of this strategy Volvo CE, in cooperation with Finland's Norrhydro, is developing a new technology that is set to revolutionize machine hydraulic performance. When commercialized, the potential customer and climate benefits are expected to be radical, with machine fuel efficiency significantly increased and CO2 emissions being cut, according to the companies.

While the full details of the technology are closely guarded, the Norrhydro system, NorrDigi, uses a multi-chamber digital hydraulic actuator that improves system efficiency that much of a machine's hydraulic system can be discarded or downsized. It removes the need for a main control valve — the heart of a traditional hydraulic system — along with excessive pump capacity, piping and hoses. It uses less energy and offers the prospect for downsizing the engine capacity.

The ongoing validations of the solution have demonstrated both efficiency improvement and an increased machine productivity. With carbon dioxide emissions reduced, it is making a radical cut in the machine's carbon footprint, the companies said.

Volvo CE and Norrhydro have signed a multi-year agreement where Volvo CE will continue to develop the technology in partnership with Norrhydro, and subsequently aim for first mover advantage. Volvo CE has exclusive rights to its use in its products during the development process.

Smart Cylinders

Unlike traditional cylinders with two chambers — one pushing, one pulling — the digital hydraulic actuator uses four chambers that can be connected in up to 16 different permutations, depending on the load required by the desired operation.

"It's a bit like a 16-speed linear transmission," said Peter Stambro, vice president business development at Norrhydro.

"Multi-chamber cylinders have been around for a while, but what makes our ones exceptional is the way they have been combined with advanced electronic control systems, whose complex algorithms and computational speed allow for instant response, but using only a fraction of the energy for the same machine maneuver or action compared to a traditional system."

"This is a prime example of how partnerships with outside experts can accelerate our own sustainability journey through technical innovation," said Thomas Bitter, head of technology at Volvo CE.

"In research so far, the system shows greatest benefits in larger machines — in the case of excavators, those 30 tons and above. However, in the future, the technology could also be used in electric machines, where its much greater hydraulic system efficiency would effectively extend the battery life and operating window," said Bitter.

Entering Field Test Phase

With a Volvo EC300E 30 ton excavator as a test bed, the technology has passed its initial proof-of-concept phase and durability tests, and is now moving to a field test period, where prototypes are used in real world applications by selected customer partners. It is forecast that the system will be offered on the company's excavators by 2024 at the latest.

"The ability to develop this radical technology in partnership with a leading player in the construction equipment industry offers many advantages, including accelerating the time to market for commercialized products," said Yrjö Trög, CEO of Norrhydro. "We will invest in a new multi-million euro world-class manufacturing facility in support of the launch, and I look forward to the market introduction of the NorrDigiTM system together with Volvo CE."

For more information, visit www.volvoce.com.