车用尿素设备喷嘴会损坏的原因

日期:2020-12-30 | 人气:123

1、 SCR体系长时间不作业

1. SCR system does not work for a long time

尿素喷嘴坐落排气管中,长时间处于高温环境中,而它作业时正是经过车用尿素设备的循环进行冷却,假如得不到尿素溶液的冷却作用,尿素喷嘴也简单呈现损坏的状况。SCR体系长时间不作业会导致SCR体系内残留的车用尿素溶液结晶阻塞管道及喷嘴,又由于长时间缺少液体的浸泡使SCR体系各零部件的寿命下降乃至损坏。

The urea nozzle is located in the exhaust pipe and has been in the high temperature environment for a long time. When it works, it is cooled through the cycle of the vehicle urea equipment. If the cooling effect of urea solution is not available, the urea nozzle will be damaged. If SCR system does not work for a long time, the residual urea solution in SCR system will crystallize and block the pipeline and nozzle. Moreover, due to the lack of liquid immersion for a long time, the service life of SCR system components will be reduced or even damaged.

2、 客观因素

2. Objective factors

SCR体系中发作杂乱的物理和化学反响,包含尿素溶液的雾化、破碎、蒸腾、液滴与排气的能量和动量交流,粒子撞壁进程,液膜构成,Nox的催化还原反响等,并且尿素喷发后构成的雾化场和温度场随发动机运转工况的变化而时间发作改动,尿素液滴在分解为氨气时,也生成氰酸、缩二脲、三聚氰酸等中心产品,简单构成尿素结晶石等沉积物。沉积物会不断累积,也会构成喷嘴阻塞。

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The physical and chemical reactions in SCR system are disordered, including atomization, breaking, transpiration of urea solution, energy and momentum exchange between droplet and exhaust, particle wall collision process, liquid film composition, NOx catalytic reduction reaction, etc. the atomization field and temperature field formed after urea eruption change with the change of engine operating conditions. When urea droplet decomposes into ammonia, the time of atomization and temperature field changes It also forms cyanic acid, biuret, cyanuric acid and other central products, which simply forms urea crystal stone and other deposits. The deposit will accumulate continuously, which will also cause nozzle blockage.

3、 车用尿素溶液质量不合格

3. The quality of vehicle urea solution is unqualified

市场上价格低廉的残次车用尿素溶液中的不容物和杂质过多会构成喷嘴阻塞损坏。

Too many impermeable substances and impurities in the low-cost defective vehicle urea solution in the market will cause nozzle blockage and damage.

4、 尿素溶液喷嘴喷发后溶液剩余

4. Residual solution after spraying of urea solution nozzle

发动机焚烧关闭后,喷嘴管路中的尿素残留液会结晶构成管路及喷嘴阻塞。

After the engine is shut down, the residual urea liquid in the nozzle pipe will crystallize and form the blockage of the pipe and nozzle.