In fact, most of the slow unloading is due to small-scale mixer. Is that because of its small volume? Of course, the slow unloading is related to the hydraulic pump and hydraulic motor. Generally, the hydraulic motor of small-scale mixer is quantitative gear pump. Its working speed is not so fast, and even the fuel valve will not be significantly improved, and the accelerator will burn for a long time The gear oil pump is broken. There is also a kind of hydraulic pump of the mixer truck, which is a plunger type variable pump. The speed of the mixer truck is generally slow in the transportation process, but when unloading, the speed is fast, and the discharge is fast. What should I pay attention to when driving a concrete mixer? What's my experience in driving a mixer? I'm often asked. Many enthusiastic car drivers also give me many good answers and suggestions, but they are all scattered. Then I'll give you a detailed list of them for your reference.

为了提高水泥的运输效率，减少袋装水泥造成的资源浪费，目前绝大多数水泥都采用散装水泥罐车运输，因水泥罐车都采用气力输送卸料，卸料速度和卸料剩余率是考核水泥罐车卸料效率的重要指标。如何保证罐内水泥尽量卸完、卸尽，采用正确的方法非常重要。因卸料过程中罐内水泥无法肉眼直观看到，必须借助一些方法才能辨别水泥卸料情况，下面给大家介绍几种简易判别水泥是否卸完的方法：

In order to improve the transport efficiency of cement and reduce the waste of resources caused by bagged cement, most of the cement is transported by bulk cement tankers at present, because the cement tankers are transported and unloaded by pneumatic means, and the unloading speed and the residual rate of unloading are important indicators to assess the unloading efficiency of the cement tankers. It is very important to adopt correct methods to ensure that the cement in the tank is discharged as much as possible. Because the cement in the tank cannot be seen directly by the naked eye during the unloading process, some methods must be used to identify the unloading situation of cement. Here are some simple methods to determine whether the cement has been unloaded:

压力表检查法，散装水泥罐车在卸料时，罐内空气压力为1.8～2.4公斤/平方厘米，卸料快结束时，气压快速下降，如果压力表降到0～0.2公斤/平方厘米之间，则证明罐内水泥基本卸完。

Pressure gauge inspection method: when the bulk cement tank truck is unloading, the air pressure in the tank is 1.8-2.4 kg / cm2, and when the unloading is finished, the air pressure drops rapidly. If the pressure gauge drops to 0-0.2 kg / cm2, it proves that the cement in the tank is basically unloaded.

卸料时间判别法，正常水泥罐卸料速度一般为每分种1～1.2吨，如果水泥装载重量为32吨，则一般需要半小时左右卸完，所以可以根据卸料吨位计算卸料时间，这样前25分钟操作人员比较轻松，没有必要长时间紧盯压力表或通过其它方法检查是否卸完。

According to the judgment method of unloading time, the unloading speed of normal cement tank is generally 1-1.2 tons per minute. If the loading weight of cement is 32 tons, it usually takes about half an hour to unload. Therefore, the unloading time can be calculated according to the unloading tonnage. In this way, the operators in the first 25 minutes are relatively easy. It is not necessary to stare at the pressure gauge for a long time or check whether the unloading is completed by other methods.

空压机声音辨别法，正常卸料时空压机负载大，空压机工作时发出的声音比较沉闷，罐体卸料结束时，空压机负载变小，工作声音变得清脆。

Air compressor sound identification method: the load of the air compressor is large in normal unloading time and space, and the sound produced by the air compressor during operation is relatively dull. At the end of tank unloading, the load of the air compressor becomes smaller and the working sound becomes crisp.

敲打罐体法，水泥卸料过程中，可以用手敲打罐体，如果声音没有回音，则证明罐体内水泥余料较多，还要卸一段时间;如果罐体有回音，证明罐体内水泥快卸完了。

In the process of cement unloading, the tank can be knocked by hand. If there is no echo in the sound, it is proved that there is a lot of cement surplus in the tank and it needs to be unloaded for a period of time; if there is echo in the tank, it is proved that the cement in the tank is almost discharged.

卸料软管观察法，正常卸料时，卸料软管受流化水泥冲击，软管不断抖动，如果软管不再抖动，也可证明罐内水泥基本卸完。

Observation method of unloading hose: during normal unloading, the unloading hose is impacted by fluidized cement, and the hose keeps shaking. If the hose does not shake, it can also prove that the cement in the tank is basically discharged.

水泥接收塔顶扬灰辨别法，正常卸料时，水泥消耗的气量相对较少，“料多气少”，接收塔顶扬灰较少，卸料后期“料少气多”，接收塔顶扬灰增多。

According to the identification method of lifting ash on the top of the cement receiving tower, during normal unloading, the gas consumption of cement is relatively small, "more material and less gas", less lifting ash on the top of the receiving tower, and "less material and more gas" at the later stage of unloading, more lifting ash on the top of the receiving tower.

当空压机加压过程中因其他原因而停止空压机工作时，应关闭前后仓的近期球阀，然后把外接气源打开，过一会再关闭外接气源，打开前后仓的进气球阀。

When the air compressor stops working due to other reasons in the process of pressurization, the short-term ball valve of the front and rear silos shall be closed, then the external air source shall be opened, and then the external air source shall be closed later, and the air inlet valve of the front and rear silos shall be opened.

通过以上方法中的一种或二种就可简单的辨别水泥是否卸完，各类水泥罐车由于结构不同、选用空压机不同、水泥接收塔的高度不同，以及所装水泥的比重不同，在卸料速度和剩余率也会有所不同，司机可通过记录实际操作方法和卸料时间，不断总结经验，获得的操作方法，达到的卸料效率。

One or two of the above methods can be used to simply identify whether the cement has been unloaded. Due to different structures, different air compressors, different height of cement receiving tower, and different proportion of cement loaded, the unloading speed and residual rate will be different. The driver can record the actual operation method and unloading time, and constantly summarize experience to obtain the most Good operation method to achieve the highest discharge efficiency.