自上料搅拌车在建筑工地上使用较多，属于专用车的一种，随着社会的发展，自上料搅拌车的使用越来越广泛，很多的大车在冬天启动的时候，都是先让发动机响一会儿，再起步行驶，这就叫做热车，自上料搅拌车为什么要热车呢？

Since the loading mixer is widely used in construction sites, it belongs to a kind of special vehicle. With the development of society, the use of self loading mixer truck is more and more extensive. When many large vehicles start in winter, they make the engine ring for a while, and then start driving. This is called hot car. Why do self loading mixer truck need hot car?

一般情况下，专用车的发动机的正常使用温度在85℃-95℃之间，当发动机在这个温度的时候，其它各部分的配合间隙正好在设计的范围内，燃烧室内的燃烧状态比较好，发动机的热效率和各方面性能处于状态，如果低于这个温度，那属于发动机过冷，这会对发动机的使用寿命造成很大的影响的。

Under normal circumstances, the normal operating temperature of the engine of a special vehicle is between 85 ℃ and 95 ℃. When the engine is at this temperature, the fit clearance of other parts is just within the design range. The combustion state in the combustion chamber is relatively good, and the thermal efficiency and all aspects of performance of the engine are in the state. If it is lower than this temperature, it belongs to the engine supercooling, which will damage the engine The service life has a great impact.
              

经研究表明，发动机的磨损在80%是发生在冷启动的一瞬间，发动机在低温时的磨损是正常工作温度的6倍；发动机在40℃-50℃时，发动机的磨损增加60%-80%，功率降低25%，油耗增加8%-10%，机油的性能衰减也更快，如果是在气温比较低的北方，自上料搅拌车的热车时间将会更长。

The research shows that 80% of the engine wear occurs at the moment of cold start, and the engine wear at low temperature is 6 times of the normal working temperature; when the engine is at 40 ℃ - 50 ℃, the engine wear increases by 60% - 80%, the power decreases by 25%, the fuel consumption increases by 8% - 10%, and the oil performance decays faster. If it is in the north where the temperature is relatively low, the warm-up time of the self loading mixer will be reduced It will be longer.

自拌混凝土搅拌车，低温除了影响发动机外，还会对其它方面的性能造成影响，比如低温会导致电瓶容量大幅度下降，车辆启动困难；还可能会导致轮胎变硬、变脆，与地面的附着力降低，车辆的操控性下降，减震器的油液粘度增加，缓冲吸振的能力会下降，车辆就会发生异响，乘坐的舒适性就会下降；变速箱的油的粘度变大，造成换挡困难。

In addition to affecting the engine, low temperature will also affect other aspects of the performance of the self mixing concrete mixer. For example, low temperature will lead to a substantial decline in battery capacity and difficulty in starting the vehicle; it may also lead to hardening and embrittlement of the tires, reduction of adhesion to the ground, reduction of vehicle handling, increase of oil viscosity of shock absorber, decrease of shock absorption capacity and increase of vehicle stability There will be abnormal noise, and the ride comfort will be reduced; the viscosity of the oil in the gearbox will become larger, which will make it difficult to shift.

现在的很多的混凝土搅拌运输车会安装节温器、使用风扇离合器或者电子风扇、自动调节开度的百叶窗、内置式排气管等等，来缓解低温对发动机造成伤害。但是在低温状态下热车还是非常有必要的，热车的时间也要适当，一般在一分钟左右就差不多了。

Now many concrete mixer trucks will install thermostat, use fan clutch or electronic fan, automatically adjust the opening of the shutter, built-in exhaust pipe and so on, to alleviate the low temperature damage to the engine. However, it is necessary to heat up the car at low temperature. The time of heating up the car should be appropriate, generally about one minute.