Features and functions of mobile asphalt mixing equipment

Asphalt mixing equipment has a special function, which is that it can perform cyclic heating to make the asphalt product reach the best condition. But how does it achieve this function? Everyone is curious about this.

The first step in establishing an asphalt mixing station is to determine the host machine and feed batching system. Generally, the configuration is based on the project’s construction period, total amount of concrete, daily concrete consumption and other indicators. The basic principle is to meet the daily concrete consumption. Under normal circumstances, a project can only have one asphalt mixing station, or separate mixing stations can be set up according to zones, or a large mixing station can be set up together with an appropriate number of concrete transport trucks, all of which depend on the actual situation.

Introduction to asphalt mixing plant Asphalt is a product of petroleum distillation.
Asphalt is a dark brown complex mixture of hydrocarbons of different molecular weights and their non-metallic derivatives. It is a kind of high-viscosity organic liquid. It often exists in the form of liquid or semi-solid petroleum. The surface is black and soluble in carbon disulfide and carbon tetrachloride. Asphalt is an organic gelling material that is waterproof, moisture-proof and anti-corrosive.
Asphalt can be mainly divided into three types: coal tar asphalt, petroleum asphalt and natural asphalt: among them, coal tar asphalt is a by-product of coking. Petroleum asphalt is the residue after crude oil distillation. Natural asphalt is stored underground, and some form mineral layers or accumulate on the surface of the earth’s crust. Asphalt is mainly used in industries such as coatings, plastics, rubber, and paving roads.

The drying drum of the asphalt mixing plant should pay attention to daily inspection, correct operation and reasonable maintenance, so as to extend its service life and reduce the cost of engineering use.
1. Pay attention to daily inspection. Before the asphalt mixing plant officially works, the drying drum needs to be tested and inspected to see whether each pipeline is reliably connected, whether the lubrication of the whole machine is feasible, whether the motor can be started, whether the functions of each pressure valve are stable, whether the instrument is normal, etc.
2. Correct operation of the mixing station. At the beginning of the asphalt mixing plant, manual operation can only switch to automatic control after reaching the specified production capacity and discharge temperature. The aggregate should be dry and have a standard mode so that it can maintain a constant temperature when flowing through the drying drum. When the entire aggregate is sent to dry, the moisture content will change. At this time, the burner should be used frequently to compensate for the change in moisture. During the rolling stone processing, the amount of water directly formed is basically unchanged, the amount of combustion accumulation increases, and the amount of water in the deposited accumulation material may change.
3. Reasonable maintenance of the asphalt mixing plant. Aggregates should be deactivated when the asphalt mixing plant is not in operation. After work every day, the equipment should be operated to discharge the aggregate into the dryer. When the material in the hopper leaves the combustion chamber, the combustion chamber should be closed and allowed to idle for about 30 minutes to cool down, so as to reduce its impact or make the machine run in a straight line. Install the drying cylinder fixing ring on all rollers synchronously.

Highways basically use asphalt materials, and asphalt mixing plants can be used to produce a variety of asphalt mixtures. So what are the mixing methods of asphalt mixing plants?
According to the mixing method, it can be divided into: continuous drum type and intermittent forced type. Continuous drum type, that is, the production is produced by continuous and uninterrupted mixing method, and the heating and drying of aggregates and the mixing of mixtures are carried out continuously in the same drum.
Forced intermittent type, that is, the heating and drying of aggregates and the mixing of mixtures are forced to be carried out periodically. The equipment mixes one pot at a time, and each mixing takes 45 to 60 seconds. The output depends on the equipment model.

What should I do when the reversing valve in the asphalt mixing plant fails? The editor has a trick:
1. The reversing valve cannot be reversed or the reversing action is slow, which is generally caused by poor lubrication, stuck or damaged springs, oil or impurities stuck in the sliding parts. In this regard, you should first check whether the oil mist is working normally; whether the viscosity of the lubricating oil is appropriate. If necessary, the lubricating oil should be replaced, the sliding part of the reversing valve should be cleaned, or the spring and reversing valve should be replaced.

After use, asphalt mixing equipment needs to be disassembled, cleaned, and maintained before it can be saved for next use. Not only is the disassembly process of the equipment important, but the previous preparation work also has a greater impact, so it cannot be neglected. Please pay attention to the detailed introduction below for specific content.

Certain failures cannot be avoided during the use of the asphalt mixing plant. For example, a malfunction of the cold material feeding device may cause the asphalt mixing plant to shut down. This may be due to a malfunction in the asphalt mixing plant or due to gravel or foreign matter being trapped under the cold material belt.

During the operation of the asphalt mixing plant, the quality of the mixture is often related to its construction quality. Therefore, we need to improve the quality level of the mixture as much as possible, and the temperature of the mixture is one of the standards for the qualification assessment of the mixture. In other words, if the temperature is too high or too low, the mixture may become waste and cannot meet the needs of use.
Therefore, reasonable control of the temperature of the mixture is one of the basic conditions that must be met for the normal production of the asphalt mixing plant. Among them, the quality of the fuel will affect the temperature of the mixture. For example, if the quality of the fuel is poor, the calorific value is low, and the combustion is incomplete, it will lead to unstable heating, low temperature, and a large amount of residue will be produced after combustion, affecting the quality of the mixture. If the viscosity is large, it will also cause ignition difficulties and the temperature is not easy to control.

Asphalt mixing plants, what role? Asphalt mixing plants, also known as asphalt concrete production equipment, is a special facility for mixing, heating, dust removal and other process treatments for raw materials such as sand, mineral powder, asphalt, etc., to produce asphalt concrete for road construction. As an indispensable role in road construction, the responsibility of the asphalt mixing plant is not only to complete the production of asphalt concrete, but also to provide solid guarantee for road construction.

Safety is the key point for any piece of equipment, and asphalt mixers are of course no exception. What I want to share with you is the knowledge in this area, that is, the safe operation specifications of asphalt mixers. You might as well pay attention to it.
In order to prevent the asphalt mixer from moving during work, the equipment should be placed in a flat position as much as possible, and at the same time, use square wood to pad the front and rear axles so that the tires are elevated. At the same time, the asphalt mixer must be provided with secondary leakage protection, and it can only be started after the inspection, trial operation and other aspects are qualified.

Asphalt mixing plant is also called asphalt mixture mixing equipment, which is mainly used to produce asphalt mixtures of various specifications. It is an important equipment in projects such as road construction, highway maintenance and airport runway construction. The main components of an asphalt mixing plant include cold material supply system, drying drum, screening system, weighing system, agitator, finished product silo and control system.
The workflow of an asphalt mixing plant is generally as follows:

If you look at an asphalt mixing plant from a professional perspective, do you know how to judge its work and significance? In fact, the so-called asphalt mixing station is the one that produces asphalt. We can usually see it in road construction projects. Specifically, it mixes some materials that need to be used during the construction process according to certain proportion requirements. Then complete the corresponding construction work.
Then, we can analyze it from a market perspective. Since it was used in the market, it has been widely praised by users. Today’s asphalt mixing plant technology has been greatly improved, and the entire set of equipment used has a variety of advantages. , such as meeting the requirements of stable control, screening, efficient dust removal, excellent mixing, and green environmental protection during the work process. It is even more obvious when used in large-scale projects such as high-grade highways and airports.

There is also a reversing valve in the asphalt mixer, which generally does not cause problems, so I have not understood its solution in detail before. But in actual use, we encountered this kind of failure. How should we deal with it?

Main uses of asphalt mixing plant
Asphalt mixing plant, also called asphalt concrete mixing plant, can produce asphalt mixture, modified asphalt mixture, and colorful asphalt mixture, fully meeting the needs of constructing expressways, graded highways, municipal roads, airports, ports, etc.
The overall composition of asphalt mixing plant
Asphalt mixing equipment mainly consists of batching system, drying system, incineration system, hot material improvement, vibrating screen, hot material storage bin, weighing mixing system, asphalt supply system, powder supply system, dust removal system, product silo and control system, etc. Some composition.

At present, the assembly and installation technology of large-scale asphalt concrete mixing equipment in high-grade highway construction is gradually improving. In order to improve work efficiency, it is necessary to analyze the pretreatment agent for the selection and matching of large-scale mixing equipment and auxiliary equipment, and clarify the installation and commissioning of asphalt stations. With the continuous change of highway construction methods, it is necessary to adopt production equipment according to the requirements of the development of the times. Intermittent asphalt mixing equipment is a widely used road construction equipment with the characteristics of simple operation and high work efficiency. Relevant staff are required to master the installation, construction and management methods of mixing equipment.

Asphalt concrete, as the name implies, is a composite material formed by combining asphalt and concrete. Its main components usually include three categories, aggregate, filler and asphalt. Aggregate, as the basic skeleton of asphalt concrete, is mainly composed of crushed stones of different sizes. These crushed stones are carefully selected and proportioned to ensure the strength and stability of asphalt concrete. Filler usually refers to fine-grained materials such as stone powder, which are filled between crushed stones to increase density and improve overall strength. Asphalt is a binder that can tightly bond aggregate and filler together to form a solid whole. In the process of producing asphalt concrete, the proportion of various raw materials will be adjusted according to different formulas. These formulas are usually formulated according to the specific requirements of the road and the use environment to ensure that asphalt concrete can meet various complex road conditions. The place where this composite material is produced is a special asphalt mixing plant. This is an asphalt concrete mixing plant. The large trucks that we see every day to transport asphalt concrete come out from here. In the asphalt mixing plant, the entire production process is finely divided into multiple steps.
First, workers use loaders to deliver aggregates into cold silos. Cold silos are usually divided into several different chambers according to the size of aggregate particles, and each chamber corresponds to aggregates of different specifications. In this way, in the subsequent mixing process, the proportion of various aggregates can be accurately adjusted according to customer needs.
Next, these aggregates will be sent to the drying drum through a vibrating feeder and a belt conveyor. In the drying drum, the aggregates will be heated to a specified temperature by the high-temperature heat source provided by the burner. During this process, the spiral blades and sheep feed plates inside the drum will ensure that the aggregates are fully heated during rotation and remove the moisture in them. In this way, not only can the bonding strength between aggregates and asphalt be improved, but also the stability and durability of asphalt concrete after paving can be ensured.

If asphalt mixing stations want to get approval results as soon as possible and operate normally, they must have corresponding environmental protection conditions. The manufacturer will introduce to you what environmental protection conditions asphalt mixing stations should have.
1. Low energy consumption
This is what asphalt mixing stations must meet. Under the same quantity and quality, the less energy the asphalt mixing station consumes during operation, the more it meets the requirements of environmental protection, such as low consumption of water and electricity resources.
2. Reduce pollution emissions
During the operation of asphalt mixing stations, the adverse effects on the environment should be reduced and pollutants should be better controlled, so that they can be defined as environmentally friendly asphalt mixing stations. At the same time, the requirements of site planning must be met. Whether it is the production area or the conversion area of ??wastewater and waste gas, the corresponding environmental protection requirements must be met.
3. High production efficiency
An environmentally friendly asphalt mixing station must not only reduce energy consumption and reduce the emission of pollutants during the entire production process, but also achieve good production efficiency.

The drying and heating system of the asphalt mixing plant can be regarded as an important part of the whole, so in actual work, it treats the material in a countercurrent heating manner, thereby achieving full dehydration of the cold aggregate, and heating it to a certain temperature, thereby providing the necessary conditions for the normal and continuous operation of the asphalt mixing plant.
During the entire heating process of the asphalt mixing plant, the main purpose is to make the performance of the mixture more in line with the requirements of use, and to make the finished material have good paving performance. Under normal circumstances, the heating temperature of the aggregate is about 160℃-180℃.

Bitumen, a black or brown petroleum-like material, has a viscosity ranging from a viscous liquid to a glassy solid. It can be obtained as a residue separated from natural deposits. Bitumen consists of hydrogen and carbon compounds with small amounts of nitrogen, sulfur and oxygen. The preparation of mixed materials for mixing with asphalt is done in several steps:
Prediction: According to the asphalt recipe, the individual components of the aggregate are weighed. Usually this is done using a belt scale, since the material must go to the next step in a continuous flow.

Emulsion bitumen equipment has stable product quality, closed material transmission, high degree of automation and civilized production, and is easy to standardize management. The double-mill configuration can be used to produce modified emulsified asphalt.
At present, emulsified asphalt equipment is widely used in new technologies and processes for preventive maintenance, such as fog seal, slurry seal, micro-surfacing, cold regeneration, crushed stone seal, cold mix and cold patch materials.
Emulsion bitumen equipment is an emulsion at room temperature formed by dispersing asphalt into the water phase. It is a new material for the use of elements. Compared with traditional hot asphalt, it saves more than 50% of energy and 10%-20% of asphalt, and has little pollution. The biggest feature of emulsified asphalt is that it can be stored at room temperature. It does not need to be heated during spraying and mixing, nor does it need to heat the stone. Therefore, it greatly simplifies the construction, avoids burns and scalds caused by hot asphalt, and avoids the fumigation of asphalt steam when paving high-temperature mixtures. It is very popular among road maintenance workers.

The plug valve is a rotary valve in the shape of a closure or plunger. After rotating 90 degrees, the channel opening on the valve plug is the same as or separated from the channel opening on the valve body to complete opening or closing. It is widely used in oilfield excavation, transportation and refining equipment, and such valves are also needed in asphalt mixing plants.
The valve plug of the plug valve in the asphalt mixing plant can be cylindrical or conical. In the cylindrical valve plug, the channel is generally rectangular; in the conical valve plug, the channel is trapezoidal. These shapes make the structure of the plug valve light and very suitable for blocking and connecting media and diversion.

Asphalt concrete mixing equipment generally uses conveyor belt conveyors to transport cold materials. Its main advantages are large conveying capacity, continuous operation, simple equipment structure and automatic control. However, belt deviation is a common fault, which directly affects the drying operation of the drying drum and also affects the production efficiency of the mixing equipment. Therefore, it is very important for the asphalt mixing station to solve the belt deviation problem at the operation site of the asphalt concrete mixing equipment.

The development prospects of asphalt mixing plants are very good, and the product competition on the market is also very fierce. When the equipment is used, uneven wear of the supporting wheels and wheel rails often occurs, and sometimes there are some abnormal noises and edge gnawing. The main reason is that after the asphalt mixing station has been working for a period of time, the drying cylinder is exposed to high temperature and friction occurs between the supporting wheel and the wheel rail.
Under the action of drying materials in an asphalt mixing station, the equipment will vibrate violently, which will directly lead to improper adjustment of the gap between the wheel rail and the supporting wheel, or mutual interference between the two. The position is skewed, so the operator needs to add grease to the surface contact positions of the supporting wheel and the calibrating wheel rail after every day’s work.

Modified Bitumen

Asphalt mixing stations have always been criticized for pollution due to the emission of harmful smoke and dust and high energy consumption. Asphalt mixing stations with high pollution, high energy consumption and unqualified environmental protection are obviously incompatible with modern urban development. Under the high pressure of environmental protection supervision, how can asphalt mixing stations pass environmental protection inspections smoothly? Can asphalt mixing stations be low-carbon, energy-saving, and environmentally friendly, and achieve environmental protection upgrades?
As a professional asphalt mixing equipment R&D and manufacturer, how to make asphalt mixing stations more environmentally friendly and energy-saving has always been the direction of Nanfang Road Machinery’s efforts. In response to the pollution problems faced by asphalt mixing stations, Nanfang Road Machinery has launched environmentally friendly asphalt mixing equipment with strict environmental protection standards.

The driving device is one of the important components of the asphalt mixing plant, so whether it can operate reliably must be highly valued to avoid adverse effects on the entire asphalt mixing plant. In order to ensure that the driving device in the asphalt mixing plant is indeed complete and reliable, the following maintenance measures are essential.

The asphalt mixing equipment mentioned here may also refer to an asphalt concrete mixing plant. At present, asphalt mixing equipment generally uses a complete set of equipment for mixing. So what are the benefits of using a complete set of equipment?
1. More effective.
In today’s industrial production, a complete set of asphalt mixing equipment can help improve production efficiency and ensure product quality. This is why even in a mixing plant, the equipment used is a complete set of equipment.
2. Ensure quality.
When mixing asphalt, a certain ratio is set. For this type of asphalt liquid used in different occasions, its ratio control has strict requirements. It is necessary to determine its mixing method and mixing time to ensure that the asphalt liquid is consistent with the production site. One of the advantages of a mixing plant is that the quality can be effectively controlled.
3. It can be sampled.
After mixing at the mixing plant, the quality inspector can sample and inspect to ensure that the mixed asphalt liquid meets the use requirements.
In short, asphalt mixing equipment will use a complete set of equipment, mainly to facilitate the later asphalt to meet production needs. Through the mixing plant, the mixing time and feeding sequence can be better controlled, so that the mixed product can meet different use requirements. And after using the archiving equipment, effective spot checks can be carried out, which can better ensure that the quality meets the construction requirements.

The basic working principle of the green asphalt mixing plants can be roughly summarized in the following ways:
To put it simply, an asphalt plant is actually a set of equipment that can mix several materials according to a predetermined ratio to form a relatively uniform mixture. It is currently widely used and is very important for the construction of different projects. Its performance Various aspects also have a great impact on the engineering quality of asphalt pavement.
Asphalt mixing plant equipment is usually divided into two structures. The intermittent type is relatively more complex in structure and process. The aggregates need to be screened twice and then measured in batches. The batching accuracy is higher. , the mixing quality is good and can meet different construction requirements. The continuous type has a slightly lower accuracy due to its simple structure and simplified operating procedures.

When using an asphalt mixing plant, first of all, it needs to have good stability. If it does not have good stability, then the asphalt mixing plant will not be able to meet the requirements of the project in terms of requirements or mass production. For road construction, the measurement requirements of asphalt concrete are relatively strict and precise. Only qualified asphalt concrete can make the quality of road construction meet the actual requirements. Therefore, the stability of the asphalt mixing plant is very important.