Power management company Eaton has introduced membrane valves for Diesel Exhaust Fluid (DEF) tanks that are specifically designed to help truck manufacturers meet the Euro 6 exhaust emission regulations that took effect earlier this year. These new valves provide a more reliable method for venting tanks than mechanical valves.
Most Euro 6-compliant trucks are now equipped with tanks filled with DEF – commonly known as AdBlue. This water-based urea solution is injected into the exhaust stream to reduce mono-nitrogen oxides (NOx) into harmless water (H2O) and nitrogen (N2). However, as AdBlue is water-based, there is the potential for ice-crystals to form in cold climates.
Traditional float-based mechanical valves are used to vent the tanks; however, ice-crystals could damage these valves or prevent them from closing fully resulting in the risk of leakage. Eaton’s innovative membrane valves consist of a single part with no moving components, which eliminates the problems associated with ice-crystals enhancing reliability in all environments. There is also no risk of DEF leakage, so truck manufacturers can be assured that the system is safe and working efficiently.
Eaton’s membrane valves are built with advanced materials and welded directly to the tank, which eliminates the need for special valve sealing and also contributes to ensuring zero leakage. The result is valves that maximise efficiency while guaranteeing long-term venting and pressure relief. Unlike standard valves, Eaton membrane valves do not require space within the tank yet still meet external height requirements.
“With the Euro 6 regulation now in force, reducing exhaust emissions has become a top priority for truck manufacturers and our membrane valve technology is helping them achieve this important goal,” said Stefan Walter, application engineering manager, Eaton. “Membrane valves are designed to offer reliable performance even in the harshest environmental conditions, contributing to the Selective Catalytic Reduction (SCR) system’s efficiency and durability.”