As people's awareness of environmental protection has been continuously strengthened, the state's emission requirements for vehicles are getting stricter and stricter. Therefore, after the introduction of the national four emission standard, most of the diesel vehicles need to install SCR post-processing system, so as to effectively reduce pollutant emissions. In the SCR post-processing system, the urea solution (hereinafter referred to as urea) plays a key role, but because the urea is easy to crystallize, so the SCR post processing system also needs to be regularly checked and maintained. What aspects should we pay attention to?

Regular cleaning of urea nozzles

The urea nozzle is one of the parts of the SCR post treatment system, which can be divided into two types from the type, one is the gas nozzle and the other is the air – free nozzle. No matter which kind of urea nozzles can be blocked and crystallized easily, if the urea nozzle is blocked, the spray effect will be lost. When the ECU computer control system recognizes such abnormality, the torque of the engine will be limited. Therefore, we say, we try to buy the positive urea as much as possible, although the inferior urea is cheaper, but the inferior urea is more likely to form the crystallization, which causes the urea nozzles to clog regularly, and it is more troublesome to clean up later.

Periodic inspection of temperature sensors

If the temperature sensor of Baotou Mercedes Benz parts fails, the exhaust temperature of the exhaust pipe can not be accurately monitored. In this case, it is possible that the temperature value of the temperature sensor feedback to the computer does not agree with the temperature of the exhaust pipe, and the urea nozzles will work in advance or not work. If the ejected urea is unable to react with the catalyst at low temperature, it will naturally generate crystals. Therefore, we should regularly check the temperature sensor working condition is normal, if the temperature sensor surface of the presence of urea crystallization, it is necessary to clean the treatment in time.

Poor quality diesel oil can not be used

The catalyst is the core part of the SCR post-treatment system. After the catalyst is chemically reacted with urea, it can effectively eliminate exhaust pollutants. But the catalyst has high technical requirements for the sulfur content emitted by diesel engine. If the engine uses inferior diesel, too much sulfur dioxide will come into the catalyst. Once the catalyst fails, the engine power output will be limited because of the excess tail gas. Therefore, inferior diesel will not only cause damage to engine parts of Baotou Mercedes Benz, but also cause many problems to the SCR post processing system.

Filter core and urea tank should be cleaned regularly

In the SCR post processing system, we should especially check the filter core soaked in urea for a long time. These filter cores not only have urea crystal, but also the filtered urea impurities. Once the filter core is blocked, the vehicle will fail to alarm. In serious case, it will affect the normal operation of the vehicle.

For urea cans, when the vehicle is in service, the bottom of the urea tank is opened and the sediment on the bottom of the tank is removed. When the vehicle is in normal operation, if the urea consumption is about 20%, urea is added to the urea tank. Try to immerse the filter core in urea so as to avoid the formation of the filter core that is not soaked in urea because of the low level of urea liquid, and the filter core will be blocked by the crystallization of urea for a long time.

Integrated above, the SCR post processing system card friends should do maintenance regularly to make the SCR post processing system in good working condition, not only can make the Baotou northern Mercedes Benz engine play a better dynamic performance, but also reduce the emission of vehicle pollutants, and play a certain effect on the net air.