Analysis of the application advantages of PLC in asphalt mixing plants

Asphalt mixing plant, also known as asphalt concrete mixing plant, is a complete set of equipment for batch production of asphalt concrete. Its efficient and stable operation is of great significance to ensure the quality of the project. It is mainly used in the construction of highways, grade roads, municipal roads, airports, ports and other projects. According to the mixing method, asphalt mixing plant can be divided into forced intermittent type and continuous production type; according to the transportation method, it can be divided into fixed type, semi-fixed type and mobile type.
The working principle of asphalt mixing plant mainly includes steps such as aggregate processing, asphalt processing and mixture mixing. Specifically, aggregates (such as gravel, crushed stone, etc.) are sent to aggregate bins through conveyors or bucket elevators, and then measured by aggregate metering devices, and a certain amount of aggregates are sent to sub-bins. Asphalt is stored in asphalt bins or oil storage tanks, and is measured by asphalt metering devices, and a certain amount of asphalt is sent to asphalt sub-bins. Finally, according to the ratio requirements, different aggregates are taken out from their respective sub-bins and sent to the mixture mixer through conveyors or bucket elevators for mixing.

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.

When inspecting the asphalt mixing plant, it was found that the asphalt in the pipeline solidified because the temperature of the asphalt transportation pipeline did not meet the requirements. Analysis believes that the reasons for this result are that the high-level oil tank of the heat transfer oil is too low, resulting in poor circulation of the heat transfer oil; the second is that the inner tube of the double-layer pipe is eccentric; the third is that the heat transfer oil pipeline is too long; and the fourth is that the heat transfer oil pipeline is not insulated measure.

Current highway projects are generally large-investment projects. When carrying out actual project construction, it is very necessary to control the cost of the project. The production cost control and management of asphalt mixing stations in highway projects plays a huge role in controlling the cost of the entire highway project, because the main expenses of highway projects are concentrated on the mixing stations, and almost all the equipment used in highway projects Materials are closely related to the mixing station.

Asphalt mixing plants bring a lot of convenience. You should understand what asphalt is. Asphalt is a very viscous liquid with a black surface that dissolves carbon disulfide. They generally exist as asphalt and smoke tar. Asphalt appeared early in social life.

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.

Due to raw materials or usage, asphalt mixing plants will be subject to a certain degree of wear or other failures during daily use. If they are not controlled or repaired in time, the problem will be further exacerbated. For asphalt mixing plants, what are the ways to prevent wear and failure?
If the asphalt mixing plant is not treated in time after being worn, it may corrode once it is in contact with air, rainwater, etc. for a long time. If the parts of the asphalt mixing plant are severely corroded, the service life and normal operation of the entire equipment will be affected.

Asphalt mixing equipment is a large-scale equipment, so you must pay attention to safety when using it to avoid accidents. But to put it simply, if you want to truly use it safely, you must master some basic common sense. The following main things must be kept in mind.

How should the working efficiency of asphalt mixing plant be improved? Let’s take a brief look.
1. Parameter setting. When using asphalt mixing plant to produce asphalt, the temperature of the hot pot can be observed through the temperature controller, but there is a certain difference between the information displayed by the temperature controller and the actual temperature. The generation of this error does not have much impact on the processing quality. If the information entered by the staff when setting the temperature is accurate, there will be no problems with the produced asphalt. It can be seen that the setting of parameters requires more attention.
2. Pay attention to avoid moisture in the equipment. When transporting and storing the asphalt mixing plant, pay attention to avoid moisture in the equipment, because there are many circuit devices inside it, if moisture, it may cause quality problems or even damage. This is also an important point to consider to improve production efficiency.
3. When installing and using the asphalt mixing plant, pay attention to whether the equipment is grounded. Before starting the equipment, it must be preheated in time so that the temperature standard can be reached within a shorter time range, so as to enter the normal asphalt production process.

Synchronous gravel sealing in road maintenance can quickly improve road driving performance, repair anti-skid performance, smoothness, etc. It is used in preventive maintenance and is also one of the methods of low-grade road pavement construction. Synchronous gravel seal has the advantages of high strength, rough surface, non-slip, impermeable, good durability, and prevention of water mist when driving on rainy days. The so-called synchronous gravel sealing layer is to use special equipment, namely the synchronous gravel sealing truck and the bonding material (modified asphalt or modified emulsified asphalt) to be spread simultaneously on the road surface, and the single layer of asphalt wear is formed by natural driving or rolling with a road roller. layer, mainly used as asphalt surface layer.

When using the asphalt mixing plant, you should regularly check the fuel pressure regulating valve or pressure reducing valve to determine whether the surface of the locking nut on the adjustable bolt is clean and removable; if the surface of the screw or nut is too dirty or rusty, it needs to be repaired or Replace the regulating valve.
Check the oil pump regularly to determine whether the sealing device is intact and whether the internal pressure is stable, and replace any damaged or leaking sealing devices. When using hot oil, check whether all oil pipes are well insulated. The filter installed between the oil tank and the oil pump must be cleaned regularly and checked for excessive wear to ensure that the fuel reaches the oil pump smoothly from the oil tank and to reduce the possibility of potential component failure.

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.

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.

Judging from the current situation of domestic highway construction, asphalt mixing stations will also achieve great development for a long time to come. This is also a result of rapid economic development. However, we have found that more and more quality problems occur when constructing asphalt pavements in modern times. Therefore, we have to put forward more stringent requirements for the quality of asphalt.

With the strengthening of the trend of environmental protection and energy conservation, the environmental protection of asphalt mixing plants has gradually become the mainstream form of mixing plant development. What kind of equipment can be called an environmentally friendly asphalt mixing plant? What are the basic conditions that must be met?
First of all, as an environmentally friendly asphalt mixing plant, it must meet the requirement of using less energy consumption during use. That is to say, under the conditions of the same quantity and quality, less energy is consumed during the operation process, including various resources such as water and electricity.
Secondly, environmentally friendly asphalt mixing plants not only require less energy consumption, but also must achieve higher production efficiency, while also reducing carbon emissions in the entire production process, so as to meet the proposed low-carbon production requirements

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.

The materials used in asphalt mixtures contain a lot of dust. When the equipment is operating, if the dust enters the atmosphere, it will cause pollution. Therefore, dust removal equipment must be installed, and now bag dust removal is the main method. Safety is a common sense issue. There are well-established standard safety rules.
Do not clean, oil or adjust any mechanical equipment that is not specifically explained during operation; turn off the power and lock it before inspection or repair activities to prepare for accidents. Because each situation has its own particularity. Therefore, be vigilant about safety damage issues, incorrect operation issues and other deficiencies. All of them may lead to accidents, personal injuries, reduced production efficiency, and more importantly, loss of life. Careful and early prevention is the best way to avoid accidents.
Careful and correct maintenance can make the equipment work more efficiently and control it within a certain level of pollution; the maintenance of each component should be carried out according to its operating standards; maintenance plans and safe operation procedures should be formulated according to the inspection and repair conditions that must be carried out.
Take out a work log to record all inspection and repair conditions, list the analysis of each inspection of each component and the description of the repair content or the date of the repair; the second step is to give the inspection cycle for each component, which should be determined according to the service life and wear condition of each component.

In the construction industry, the installation and application of asphalt mixing plants can often be seen. This kind of equipment can complete the processing process of limestone and other powder products. The equipment has a reasonable structure and high working efficiency. It can save more costs for manufacturers during the production of asphalt raw materials. Therefore, the construction and other industries now attach great importance to the application of this equipment. During the production and processing of the equipment, the staff also need to pay attention to several operating skills to ensure that the equipment can operate stably and provide more benefits for production work.

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.

1: The site should be located on higher ground and away from residential areas and densely populated areas.
Because part of the equipment of the mixing station is installed below the ground, in order to avoid continuous rainfall. The equipment will suffer disaster, and the changing aggregate moisture content will affect the concrete quality. Quality accidents are prone to occur. Therefore, during site construction, attention should be paid to the construction of drainage pipelines and sand and gravel quarries. With the rapid development of cities. With the continuous expansion of urban scale, environmental protection requirements will become more and more stringent. Urban roads prohibit gravel vehicles from passing, so concrete mixing plants should be built far away from urban areas.

Judging from the situation of highways in our country, asphalt pavement is the most used, which is one of the reasons why asphalt mixing plants have developed so rapidly. Under the situation of rapid economic development, the quality problems of asphalt pavement are gradually increasing, which puts forward higher and higher requirements for the quality of asphalt. It is understood that the primary factor that affects the quality of asphalt is the ratio of raw materials. This is also covered in the introduction of asphalt mixing stations. You can discuss it together.
In order to obtain high-quality asphalt products, in addition to the asphalt mixing equipment meeting the requirements, selecting the appropriate asphalt mixture gradation type is also a top priority. According to my country’s current regulations, the maximum particle size of the asphalt mixture in the upper layer of the highway should not exceed half of the layer thickness; while the maximum particle size of the aggregate in the middle surface layer of asphalt mixture should not exceed two-thirds of the layer thickness; and the asphalt layer should not exceed half of the layer thickness. The maximum nominal aggregate size of the pavement structural layer mixture should not exceed one-third of the layer thickness.
Based on this analysis, if an asphalt surface layer with a certain thickness is selected according to the above specifications, the particle size of the asphalt mixture aggregates will generally be larger, which will inevitably bring insurmountable construction difficulties to the construction of asphalt concrete pavement. After investigation, testing, analysis, and comparison, it can be seen that the lower layer has a wider choice, so the AG-201 gradation type can be used; while the selection of the upper layer mixture type is more difficult, and it is necessary to achieve a reasonable choice of this mix ratio. , on the one hand, we must examine as many aggregate resources as possible, and on the other hand, we must also consider the model of the mixing equipment.
In order to ensure the quality of the project, strict selection and inspection of engineering materials must be carried out. Therefore, the selection and determination of raw materials should be based on the requirements for pavement structure and use quality, combined with the supply of floor materials, and inspection in accordance with the requirements of relevant test procedures, and then Select the best materials so that all technical indicators of the materials meet the specified technical requirements.

Due to certain restrictions on the current development status and conditions, the profits of the domestic asphalt pavement construction industry are getting lower and lower. Therefore, in the process of using asphalt mixing plants for production, on the one hand, the quality of the products and customer requirements must be ensured. , on the other hand, it is necessary to reduce production costs. Therefore, cost management is very important, and refined management should be implemented in this regard.
First, for device management. Since equipment is the foundation and key of production, in the cost management of asphalt mixing stations, the management of equipment plays an important role in reducing costs. Only by managing the equipment well can the normal working status be ensured, which provides the necessary guarantee for the smooth progress of the project. In fact, in today’s highway projects, equipment costs account for a large part of the cost and profit. The huge profits after the construction of a highway will be greatly affected by the management of materials and 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.

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.

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.

Due to its complexity and importance, asphalt mixing plants are more critical in road construction. Modern asphalt mixing stations have five key systems. Do you know what they are?
1. Mixing system of asphalt mixing plant
Mixing equipment is one of the key systems, why? Usually, the productivity of the mixing equipment has a great impact on the next step of construction efficiency. Most asphalt mixing plants use twin-shaft forced mixing. Since the drying drum and burner of the mixing equipment have strong overload capabilities, and in most cases, the moisture content of the mineral materials is less than 5%, this improves the productivity of the mixing equipment. provide conditions. The mixing blades of the mixer have an adjustable assembly angle and are driven by dual mixing shafts and dual motors.

Asphalt mixing plant is one of the main equipment for producing asphalt concrete. It can mix asphalt, gravel, cement and other materials together in a certain proportion to obtain the products required for highway construction. In order to ensure its operating effect, the asphalt mixing station also needs to be powered on for trial operation before it is officially put into work.
At the beginning of the test run, first run a single motor, and at the same time check whether the current, steering, insulation and mechanical transmission parts are operating normally. After confirming that each motor and mechanical transmission parts are operating correctly, conduct a joint trial run. During the entire process, it is necessary to conduct patrol inspections of key parts. If any abnormal noise is found, the cause should be identified and eliminated in a timely manner.

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:

Speaking of asphalt mixing plants, we are not unfamiliar with them. This is a unit equipment specially used for asphalt mixing. In fact, what we really lack understanding of is its gas system. Even the accumulated failures that often occur in the gas system of asphalt mixing plants are not very clear. Facts have proved that only by properly maintaining the various systems of the equipment can efficient production and good benefits be achieved.
The following are four types of gas system failures that often occur in asphalt mixing plants. Let’s analyze the causes of the problems behind the failures one by one.

Effective maintenance of the drying drum of the asphalt mixing plant can extend its service life and reduce the cost of use. Let’s take a look at how to maintain it reasonably.
1. The drying drum should be stopped when the aggregate is not running in the asphalt mixing equipment. After the work is over every day, the equipment should be operated to discharge the aggregate into the dryer. After closing the combustion chamber, the combustion chamber should be idle for about 30 minutes to cool down to reduce the impact or allow the machine to run automatically.
2. Install the drying cylinder fixing ring on the roller synchronously. Check the environment in the patrol ring regularly. Whether the roller is adjusted, the straight roller will automatically move to the conveying end, and then the bias will be adjusted to the correct position.
3. If the roller table is in contact with only one of the two thrust rollers, the gap sheet can be filled under the support roller until it is simultaneously subjected to the full width of the support ring. The specified nutritional state should be maintained by the thrust wheel, but it is used to compensate for the desire not to express.
4. If the drying drum is equipped with a drive device, a certain amount of power should be added in small amounts.