Electrohydraulic innovation further improves fuel efficiency of volvo machines

Volvo Construction Equipment and Finnish company Norrhydro have developed a digital hydraulic actuator for construction equipment that increases productivity while significantly reducing fuel consumption and CO2 emissions. The new technology will revolutionize the hydraulic performance of machines and, if adopted on a large scale, will also help the industry meet its sustainability ambitions. The system is expected to be available on Volvo excavators by 2024.

The patented NorrDigiTM system uses a highly efficient multi-chamber digital actuator, which can reduce or even eliminate much of a machine's hydraulic assembly. It can eliminate, for example, the need for a main control valve (MCV), the heart of a traditional hydraulic system. It can also reduce the capacity of hydraulic pumps and the number of hoses and pipes on the machine. This system requires less energy, offering the possibility of reducing the size and power of the engines currently used in the machines.

Tests and evaluations of this new technology currently underway demonstrate both improved efficiency and increased productivity. The significant reduction in carbon dioxide emissions makes the equipment even more environmentally friendly. Volvo CE and Norrhydro have signed a contract whereby both companies will continue to develop this technology in the coming years. Volvo CE has exclusive rights to use the system on its machines during the development process.

Smart cylinders

Unlike traditional hydraulic cylinders with two chambers, one for compression and one for relief, the digital hydraulic actuator uses four chambers that can be connected in up to 16 different combinations, depending on the load required in the operation. "It's like a 16-speed linear transmission," says Peter Stambro, vice president of business development at Norrhydro. "Multi-chamber cylinders have been around for some time. What makes them exceptional is the way they have been combined with advanced electronic management systems, where complex algorithms and high computational speed allow instantaneous responses using only a fraction of the energy for the same maneuver or machine action, compared to the traditional model," he explains.

"Partnerships like this with external experts demonstrate how we can speed up our own path towards sustainability through technical innovation," states Thomas Bitter, Volvo CE's chief technology officer. "In the research and development carried out so far, the system shows its greatest benefits in larger equipment - in the case of excavators - those with 30 tons operating weight or more. But in the future, this technology could also be used on electric machines, where the increased efficiency of the hydraulics would effectively extend battery life and the operating window under load," says Bitter.

Field tests

Using a 30-ton EC300E excavator as a test bed, the technology passed its initial proof-of-concept and durability-testing phase. It will now move into a period of field testing, where prototypes will be used in real-world applications at selected customers.

"The ability to develop this technology in partnership with one of the top leaders in the construction equipment industry offers many advantages, including speeding up the time to market for the products," says Yrjö Trög, CEO of Norrhydro. "We will invest in a new world-class factory to support the launch. We look forward to the introduction of the NorrDigiTM system together with Volvo CE," he highlights.

Norrhydro Oy

Specializing in smart and environmentally friendly hydraulic solutions for heavy equipment, Norrhydro Oy is a hydraulic cylinder company based in Finland. In a phase of strong growth, it has just celebrated its 35th anniversary.