The urea water valve, also known as the urea nozzle, is a core component of the SCR aftertreatment system. Based on ECU instructions, it precisely measures and atomizes the urea solution (automotive urea) and injects it into the exhaust pipe. Urea decomposes into ammonia at high temperatures, which then undergoes a catalytic reduction reaction with nitrogen oxides in the exhaust gas, converting them into harmless nitrogen and water. This effectively reduces nitrogen oxide emissions from diesel engines, making it a key actuator for meeting China VI and higher emission standards.
