In order to improve the transportation efficiency of cement and reduce the waste of resources caused by bagged cement, at present, the vast majority of cement is transported by bulk cement tanker. Because the cement tanker adopts pneumatic transportation for unloading, the unloading speed and unloading residual rate are important indicators to assess the unloading efficiency of cement tanker. It is very important to adopt correct methods to ensure that the cement in the tank is discharged as much as possible. Since the cement in the tank cannot be seen visually during unloading, some methods are needed to identify the cement unloading. Here are some simple methods to judge whether the cement is discharged or not:
1. 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. When the unloading is almost over, the air pressure drops rapidly. If the pressure gauge drops to between 0 ~ 0.2 kg / cm2, it proves that the cement in the tank is basically unloaded.
2. 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 complete the unloading. Therefore, the unloading time can be calculated according to the unloading tonnage. In this way, the operator is easier in the first 25 minutes. It is not necessary to keep a close eye on the pressure gauge for a long time or check whether the unloading is completed by other methods.
3. Air compressor sound discrimination method: during normal unloading, the load of the air compressor is large, and the sound generated during the operation of the air compressor is relatively dull. At the end of tank unloading, the load of the air compressor becomes smaller and the working sound becomes crisp.
4. Knock on the tank. During the cement unloading process, you can knock on the tank by hand. If there is no echo, it proves that there is a lot of cement residue in the tank and it will take some time to unload; If the tank has an echo, it proves that the cement in the tank is almost discharged.
5. Unloading hose observation method: during normal unloading, the unloading hose is impacted by fluidized cement and the hose continues to shake. If the hose no longer shakes, it can also prove that the cement in the tank is basically unloaded.
6. Identification method of ash lifting on the top of cement receiving Tower: during normal unloading, the gas consumption of cement is relatively small, "more materials and less gas", the ash lifting on the top of receiving tower is less, and the ash lifting on the top of receiving tower is more in the later stage of unloading.