Power management company Eaton has expanded its portfolio of valvetrain solutions for diesel off-highway vehicles to help OEMs reduce emissions and improve fuel economy. Eaton’s new technology allows for cost-effective, variable valve actuation with hydraulic lash adjustment (HLA) function.

This technology enables precise valve lift control through HLA, coupled with engine braking capability, which in turn helps reduce emissions and improve fuel economy. Hydraulic lash adjusters can also support cylinder deactivation.

Eaton’s cylinder-deactivation (CDA) technology increases the exhaust temperature at low load to allow NO_x aftertreatment systems to quickly reach peak efficiency range of 250 °C – 400 °C. While other technologies can be combined to reduce both CO₂ and NO_x emissions, Eaton’s CDA stands out as one of the only technologies that can simultaneously reduce both.

Eaton’s cylinder-deactivation (CDA) technology can play an important role in helping commercial vehicle manufacturers meet or exceed 2024 and 2027 US emissions regulations.

Up until now, nitrogen oxide (NO_x) emissions regulations have targeted on-road vehicles, and those regulations have been successful in reducing NO_x in high-speed highway applications. The same technologies that reduce emissions and increase fuel economy in on-highway, low-load duty cycles are applicable to off-highway equipment—so we expect the off-highway segment to face similar pressure to reduce NO_x very soon.

—Dr. Mihai Dorobantu, director, Technology Planning and Government Affairs, Eaton’s Vehicle Group

In the commercial vehicle segment, US regulations mandate manufacturers reduce carbon dioxide by up to 20% by 2024 and up to 27% by 2027. The California Air Resources Board (CARB) is expected to mandate reductions of NO_x emissions by approximately 70% by 2024 and up to 90% by 2027. Additionally, the Environmental Protection Agency (EPA) and CARB are both evaluating new low-load cycle and in-use requirements. Similar mandated reductions in emission levels are expected in European regulations.

Dorobantu said Eaton sees strong opportunities in the commercial vehicle diesel market with products that help reduce CO₂ and NNO_xOx, including CDA technology, exhaust gas recirculation (EGR) pumps and efficient transmission technologies.

CDA is just one of Eaton’s variable valve actuation (VVA) technologies. Other technologies include late intake valve closing (LIVC) and early exhaust valve opening (EEVO), which modify valve operation to allow engine manufacturers various methods to maximize aftertreatment efficiency and minimize fuel consumption. In addition to keeping the aftertreatment system warm, LIVC also enables high compression ratios for diesel engines and fast SCR heating at engine start-up.

Having a suite of VVA technologies allows OEMs to combine different valvetrain control functions to best optimize both fuel economy and aftertreatment efficiency.

—Karl Sievertsen, vice president, Engineering, and chief technical officer, Eaton’s Vehicle Group

Eaton VVA solutions are flexible and adaptable to any valvetrain architecture, allowing OEM customers to implement multiple functions such as CDA and engine braking in tight packaging.