Why are trucks not burning urea? What happens if trucks don’t burn urea

For students who have never been in contact with diesel vehicles, they may not know that diesel vehicles often need to add urea to their vehicles. So why do diesel vehicles need to add urea? What is the reason if the truck does not "burn" the urea? What are the consequences of not "burning" urea?

Why should diesel vehicles "burn" urea?

The main purpose of adding urea to diesel vehicles is to reduce the nitrogen oxides (NOx) in the exhaust gas from diesel engines..

The NOx in diesel vehicle exhaust is mainly nitric oxide (NO).If the concentration of NO is too high, it will affect the body's chest and lung functions, causing central nervous system disorders and other hazards. At the same time, it will slowly be converted into nitrogen dioxide (NO₂), NO₂It has a strong pungent odor. Inhalation can cause diseases of the human respiratory system. At the same time, it is also one of the main causes of acid rain, which is extremely harmful to people and the environment.soIn 2008, my country's National Fourth Standards stipulated that automotive urea must be used in the emission reduction system of diesel vehicles.

Working process of car urea

SCRIs a closed-loop injection system,When the exhaust gas is discharged from the combustion chamber of the engine, the electric pump willYuanAccording to the instruction, suck a sufficient amount of urea solution from the urea tank, mix and atomize the urea solution with compressed air, and enter the spray pipe to spray the urea nozzle evenly into the exhaust gas.at this timeUrea solution decomposes at high temperature to generate NH₃, And at the same time undergo a catalytic reduction reaction with NOx, and finally produce harmless N₂And H₂Odischarge.

What is the reason why trucks do not "burn" urea?

ifdiscoverCar urea has not been consumed, or when the vehicle emission lights are on, it may be that the SCR system of the vehicle is not working (that is, people often say that urea is not "burned"), and this problem is not caused by our own hands. If it can be resolved, immediately go to a professional 4S shop for inspection and maintenance.The specific reasons may be: damage to the urea pump, blockage of the urea pipeline, blockage of the nozzle, etc.

What happens if the truck does not "burn" urea?

polluted environment:Diesel vehicles without urea will have an extremely bad impact on the ecological environment, and this is also not allowed by national laws and regulations.

Motivation becomes weaker:This is not because of the direct impact caused by not adding urea for vehicles, but the engine electronic control system will forcibly limit the torque output of the engine when the urea injection is not monitored and the exhaust pollution exceeds the standard.

Damage to the SCR injection system:If there is no urea for a long time, the nozzles, pipes and urea pumps in the SCR system may crystallize and block, or be damaged by high temperature.