What is Liu Guo?

Pacific automobile network country ⅵ refers to the sixth national vehicle pollutant emission standard, which can prevent and control the environmental pollution caused by the exhaust gas of compression ignition and gas fuel ignition engines, protect the ecological environment and protect human health.

The sixth national standard stipulates the content limits of gaseous pollutants and particulate pollutants in the exhaust of truck diesel engines and natural gas engines. Compared with National Five, National Six has raised the emission standards by more than 30%, reduced nitrogen oxides by 77% and particulate matter by 67%, introduced the limit requirements of PN (particle number), tightened the relevant requirements of emission durability and OBD, and introduced the requirements of vehicle emission test, which fundamentally guaranteed the emission standards. Compared with the national five emission regulations, the actual road emission test requirements and limits of the whole vehicle are increased.

For diesel engines, in order to meet the national emission standards, designers have made great improvements in the engine and aftertreatment system. According to the main categories, it can be divided into two categories. One is the route of efficient SCR+DOC+DPF, and the other is the route of EGR+DOC+DPF+SCR. An obvious disadvantage of high efficiency SCR is high urea consumption and high comprehensive use cost. The second category is mainly introduced here. Compared with the engine and aftertreatment system in the fifth country, the engine and aftertreatment system in the sixth country are quite different in structure and function, including electronic throttle, ERG, Venturi tube, variable cross-section supercharger, closed crankcase ventilation system and HC nozzle with DPF active regeneration.

(Photo/Text/Photo: Pacific Auto Network Lu Liting)