With the continuous development of economy, the size of the city is gradually expanding, in the process of urban engineering construction, cement is a kind of building materials must be used. To accurately transport these cement dust to the destination, it is necessary to use the bulk cement tank trailer.

Bulk cement tank trailer, also known as powder tank trailer or dust material transport vehicle, is mainly used to transport the diameter of no more than 0.1mm dust dry materials, such as cement, fly ash, lime powder and other materials.

▎In the history of cement transport truck is also the replacement of the final choice of pneumatic cement bulk trailer

In China's cement transport market, the earliest is the gravity unloading truck, it is like the new type of dump truck with a top, unloading, cargo box rises, material depends on gravity to discharge, the disadvantage of this unloading way is that the material can only be unloaded to the position of the lower than their own cargo box.

To the last century 50's, the cement transport market has a new change, can use the screw conveyor installed on the trailer unloading material, but this unloading way is easy to cause damage to the unloading aircraft, so it is not a very ideal unloading scheme.

It was not until the 1960s that the pneumatic cement bulk trailer appeared that the problem of dust material unloading was solved ideally.

This material unloading way is that the air compressor is powered by a diesel engine. The compressed gas of the compressor is transported to the tank through an intake pipeline. After fluidization device, the flow of dust material increases, showing the properties of a similar liquid, and the powder can flow on a fluidized bed with a certain inclination.

Due to the pressure difference between inside and outside the tank, when unloading the material, open the valve, and the dust material will be transported to the designated position along the discharge pipeline with the air.

▎This SUNSKY powder cement tank trailer not only saves time, effort and worry to transport cement

The SUNSKY bulk cement tank trailer introduced today has a tank volume of 40m³.

The trailer uses a Suzhou Brand air compressor, which is rated at 38kW, solvent flow rate is 12mpm and rotational speed is 1000rpm.

air compressor of bulk cement trailer

Suzhou brand air compressor is widely used in cement powder tank trailers. Judging from the feedback of previous customers, the quality of this air compressor is good and its reputation is good.

On the left side of the tank, there is a water storage tank, which can be used to drench the brakes on long downhill sections.

The material outlet pipe under the tank body is fixed around the trailer body using 12R22.5 steel wire tire. Dust material transport vehicle can parallel transport 5 meters when unloading, the height can reach 15 meters.

On the left side of the vehicle, it is mainly the piping system of the trailer. The air outlet pipe of the air compressor is communicated with the air inlet valve of the front and rear silos of the tank, and then the compressed gas is transported to the inside of the tank. The secondary blowing pipe is controlled by the secondary blowing valve and connected with the discharging pipe, which can play the role of auxiliary discharging when discharging material.

The emergence of dust material transport vehicle has solved the problem in the process of cement transport. Because the bulk cement material uses the tank transportation, it no longer needs the paper packaging, so in the transportation process can not only save manpower, improve labor productivity, but also can save raw materials, reduce transportation costs.

At the same time, this mode of transportation also solves the problem that bulk cement is easy to be affected with moisture, so that the cement material is stored in the tank for a year without deterioration, but the powder tank trailer transportation of cement is only suitable for a large number of mixing stations to use, and the use of less cement material, it still needs to use the ordinary bag packing transportation mode.

40m³ bulk cement tank truck

Pneumatic conveying system

In the feeding process, the bulk cement pull into the delivery tank through the special feeding valve. The gas in the delivery tank is released through the balance valve to facilitate feeding and eliminate the reverse pressure that impedes bulk cement flow. Once the delivery tank is filled, the special feed and exhaust valves are closed and sealed by a signal from the level gauge, electric contact pressure gauge or weighing sensor. Then pass compressed gas into the sending tank. When it reaches a certain value, the discharging valve opens automatically. The compressed gas in the sending tank mixes with the material and puts pressure on the conveying pipeline at the same time. The bulk cement is conveyed in discrete blocks until the delivery tank and the conveying line are emptied.

When the delivery line is close to empty, the pressure in the delivery tank drops to zero. At this time, the inlet valve is closed. After the gas in the delivery tank and pipeline is empty-closed, the discharge valve and balance valve are closed and the special feed valve for the delivery tank is started. Start the next feed cycle.

Negative pressure pneumatic conveying system

Negative pressure pneumatic conveying system is an advanced powder material handling equipment, has the characteristics of compact structure, reliable operation, can be horizontal, inclined and vertical conveying loose, dry powder cement material or granular material. It is suitable for bulk loading, bulk transportation and bulk unloading in the production process.

Negative pressure conveying is the formation of a negative pressure air flow under the action of a vacuum, under the action of this air flow, through the suction hose or pipe to another container bulk material. Since the material is always in a vacuum state during the conveying process, it will not leak to the surrounding environment even if the pipeline leaks.

Negative pressure system is suitable for multi-point feeding and single point discharging conditions, usually for conveying materials with light gravity.

Pressure gauge of bulk cement tank trailer

▎How to judge whether the unloading of bulk cement semi trailer is completed

✔️Pressure gauge inspection method

During the unloading of bulk cement semi-trailer, the air pressure in the tank is 1.82 kg/cm2. At the end of unloading, the air pressure drops rapidly. If the pressure gauge drops to 0~0.2 kg/cm2, it is proved that the cement in the tank is basically unloaded.

✔️Discharge time discrimination method

Normal bulk cement semi-trailer discharging speed is usually 1 ~ 1.2 tons per minute, if cement loading weight 32 tons, it takes about half an hour finish unloading, so you can according to the material weight discharging time, 25 minutes before the operator will be more relaxed, there is no need long time to watch the pressure gauge check finish unloading or by other methods.

✔️Air compressor sound discrimination method

The normal unloading space and time load of the compressor is large, and the sound made by the air compressor when it works is relatively dull. At the end of the tank unloading, the load of the air compressor becomes smaller and the working sound becomes clear.

✔️Tank beating method

In the process of cement unloading, you can knock the tank with your hand. If there is no echo, it proves that there is more cement in the tank and it will take a while to discharge. If there is echo in the tank, it proves that the cement in the tank is nearly finished unloading.

✔️Discharge hose observation method

During normal unloading, the unloading hose is impacted by fluidized cement, and the hose keeps shaking. If the hose no longer shakes, it can also be proved that the cement in the tank is basically unloaded.

✔️Cement receiving tower top ash identification method

Normal unloading, cement consumption of gas is relatively small, "more material less gas" receiving tower top ash, later unloading "less material more gas" receiving tower top ash increase.

▎The important significance of developing bulk cement career vigorously

1. The development of bulk cement is conducive to saving resources and improving economic benefits.

According to the statistics of the relevant departments of the state: every promotion of the use of 10,000 tons of bulk cement, social comprehensive economic benefits for 644,500 yuan.

2. The development of bulk cement is conducive to promoting and improving the quality of the project

Bulk cement in the production process of strict control of cement quality, especially the requirements of the stability of 100% qualified, to ensure the quality of cement production. In the process of transportation, the use of special means of transport from the production plant (or transfer station) directly sent to the user, the circulation channel is formal and clear, to eliminate adulteration or shoddy, so as to ensure the quality. In the storage process, bulk cement in the storage tank up to 13 months do not deteriorate, and cement in bags stored for 12 months, the strength of 30-50%, and easy to be affected by moisture, wet, lumpy deterioration. In the process of use, the bulk cement measurement is accurate, no loss (bag cement loss rate is 5%) to ensure the cement dosage, more ensure the quality of concrete and engineering quality.

3. The development of bulk cement is conducive to reduce noise pollution, improve the construction environment, improve labor efficiency.

Bagged cement from cement factory packaging to site unpacking use, the intermediate links, take up more labor, labor production efficiency is low. In particular, the site mixing, noise pollution is serious, affecting the construction surrounding environment. The development of bulk cement, popularize ready-mixed concrete (commercial concrete), can effectively improve efficiency, reduce the intensity of work, greatly reduce noise pollution, improve the construction environment and workers working conditions, is conducive to health.

Diesel engine of bulk cement trailer

4. The development of bulk cement is conducive to reducing dust, improving atmospheric environmental quality and sulfur dioxide emissions.

At present, the air pollution in China's major cities is in the transition period, the air pollution from coal smoke type to mixed type. The proportion of construction dust to air pollution is more than 50%, among which cement dust accounts for a large proportion. There are two main ways for cement dust to pollutes the atmosphere. One is the damage caused in the transportation process of bagged cement, as well as in the loading and unloading and storage process. The general damage rate is 5%. Only this, in 2002, the country packed 530 million tons of cement, damaged cement of 26.5 million tons, and these cement may have more than 20%, about 5.5 million tons into the atmosphere, become suspended matter pollution of the environment.The second is the dust produced when the bagged cement is unbagged and mixed, as well as the dust produced when the packaging material is recycled, will produce serious pollution. The amount of cement dust into the atmosphere is far more than 5.5 million tons, becoming the source of harm to people's health and pollution of the ecological environment. It is predicted that the national coal consumption in 2003 will be more than 1.2 billion tons, sulfur dioxide emissions will reach 27.3 million tons. If we develop bulk cement according to 90% of the national cement output, we can save 40 million tons of coal used for packaging materials every year, and reduce 900,000 tons of sulfur dioxide emissions in the air, thus greatly improving the quality of urban air.

If the use of bulk cement, from the start of the cement factory loading, in the process of transportation, storage, use all under the closed condition, and with the promotion of ready-mixed concrete, can greatly reduce or even eliminate cement dust emissions, purify the air, reduce pollution.

5. The development of bulk cement is conducive to maintaining ecological balance and has significant ecological benefits.

In 2002, the country packed 530 million tons of cement, consuming 3.18 million tons of paper to pack cement bags, equivalent to 17.49 million m3 of high-quality timber, equivalent to one fifth of the total timber cutting in the country, and about 360,000 hectares of forest were destroyed. The sandstorm in many areas of our country is directly related to the reduction of vegetation, soil erosion and desertification.

The development of bulk cement has protected at least 360,000 hectares of forest every year, equivalent to about one-twentieth of the reduction of desertification in the country. At the same time, the reduction of deforestation is conducive to the maintenance of ecological balance, regulation of global climate, with significant ecological benefits.

▎Application characteristics of bulk cement

Let's talk about the cost first. The cost of bulk cement is relatively low, of course, compared with other cement, there is less packaging this link, which can greatly reduce the cost.

Bulk cement is so widely used that you can hardly look up without seeing a cement construction project. For example, we live in a tall building with cement in summer every day, every street is made of cement, and every road is made of cement every day.

manhole cover of bulk cement trailer

▎Some examples of the use of bulk cement

First, the construction of transportation infrastructure in the transportation industry needs a lot of cement, such as the construction of roads, railways and Bridges, and so on. Any one of these jobs needs a lot of cement.

Second, it is the construction of water conservancy, hydropower construction projects, island reef construction projects, these projects left the cement is difficult to complete!

Third, there is the rural infrastructure, in the rural people are mostly their own houses, the demand for cement is very large, the construction of new countryside, every village through (through roads) irrigation and water conservancy, every year need a lot of cement.

Cement has a great help to our social development, our life is inseparable from cement, if there is no cement, then there would not be today's high-rise summer. Therefore, I hope that we can make good use of cement to bring convenience to us, and don't waste it in the process of use.