Analysis of the application advantages of PLC in asphalt mixing plants

Asphalt mixing stations, also known as asphalt concrete mixing stations, can produce asphalt mixtures, modified asphalt mixtures, and colored asphalt mixtures, which fully meet the needs of building highways, grade roads, municipal roads, airports, ports, etc. Changmeng Electric Power introduces the safety operating procedures of asphalt mixing plants below:
1. During the operation of the mixing equipment, in addition to ensuring that the equipment is in good condition, it should also be equipped with a mineral moisture content detector and a finished material tester, and the relevant data should be frequently tested for the operator to adjust the operation in time to keep the equipment in good condition.
2. In addition to affecting production capacity, the moisture content of mineral materials is also the main factor determining fuel consumption. Additional material sheds should be added.
3. Before operation, all working parts and devices of the mixing equipment should be fully checked to see if they are intact and normal. If there are any problems, they must be properly handled before operation, and it is forbidden to operate with illness.
4. The operation must be carried out strictly in accordance with the procedures and precautions specified in the instruction manual. After normal ignition, the dust collector should be monitored to ensure that the drying drum burns under negative pressure; after production starts, the hot material elevator and agitator should be monitored to see if they are working normally to coordinate the operation of other parts.

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 mixing plant is a very practical engineering machinery. Especially in the road construction process, it plays an irreplaceable role. Due to its importance, in addition to ensuring its own quality, the use and maintenance of the equipment must be carried out normally. Let’s learn about the daily maintenance requirements of asphalt mixing plants.

Asphalt mixing stations and equipment must implement secondary leakage protection measures. They can only be used after being plugged in and operated through the circuit breaker before use. During the trial operation, it is necessary to verify that the rotational speed of the mixing drum will be inappropriate.

The asphalt mixing plant is a complete set of equipment for mass production of asphalt concrete. The whole machine of the equipment consists of multiple systems, such as batching system, drying system, combustion system, powder supply system and dust prevention system. Each system is an important part of the asphalt mixing plant.
The working condition of the combustion system of the asphalt mixing plant has a great impact on the whole system, which is related to the economic efficiency of the whole system, temperature control accuracy and flue gas emission indicators. This article will briefly introduce how to judge the working condition of the combustion system of the asphalt mixing plant.
Generally speaking, due to the complexity of the detection equipment and methods, there are no conditions to achieve in the working process of most asphalt mixing plants. Therefore, it is more convenient to judge the working condition by a series of relatively intuitive factors such as the color, brightness and shape of the flame. This method is very simple and effective.

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℃.

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.

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:

The renovation of the combustion-supporting system of the asphalt mixing plant and the use of DC frequency conversion CNC machining technology are all renovations of the original system. In addition to the above renovation plans, with the existing equipment and personnel, what other measures can be taken in the application to reduce the operating costs of concrete mixing plants?
At present, China has no mandatory national industry standards for heavy residual oil, and the quality of fuel oil varies greatly. Even from the same dealer, the quality difference between batches is very large, and it contains more residues. Therefore, bridge inspection equipment should be installed on the construction site, and professional personnel should inspect various performance parameters of gasoline and diesel to strictly control quality.
When the burner is working, if the flame of the combustion aid is red and the smoke from the ash removal chimney is black, this is the manifestation of poor atomization of gasoline and diesel and insufficient combustion aid. At this time, the following measures should be taken to deal with it: properly adjust the distance between the nozzle and the vortex plate, generally push it inward to a suitable distance, the purpose is to prevent the atomized oil cone sprayed from the nozzle from spraying into the vortex plate; effectively adjust the ratio of gasoline and diesel to gas, so that the gasoline and diesel increase the mass conversion law slowly, or the gas increase the mass conversion law quickly; promptly remove the carbon deposits and coke around the nozzle to prevent the flame from deflecting; heavy residual oil contains more residues, which can easily cause serious damage to the high-pressure oil pump and increase the working pressure, affecting the actual effect of atomization and the shape of the flame, so the high-pressure oil pump must be repaired or replaced in time; install metal filter devices in front of the first and second high-pressure oil pumps, and clean them frequently to prevent the residues in the gasoline and diesel from blocking the nozzle.
The operators should be trained in professional skills on a regular basis to strengthen their job responsibilities and moral education, so that they can establish their respective job responsibilities, understand the importance of their positions, understand the content of their work, and improve their professional level. Skilled operators can properly control the temperature of the asphalt mixing plant mixture to avoid gasoline and diesel waste.
In order to improve the combustion-supporting effect and effectively reduce the operating costs of asphalt mixing stations, Sinoroader Group kindly reminds that the following issues should be noted when using the burner in the asphalt mixing station: To improve the maintenance of the burner, the burner nozzle should be cleaned of charred materials and carbon deposits on the ignition electrode regularly. The nozzle can be disassembled according to the atomization status; the air-oil ratio of the burner is generally not adjusted, and the fuel pump pressure can be adjusted according to the smoke status and the temperature of the asphalt mixture; the sulfur dioxide generated by the combustion of light fuel oil has a strong corrosion to the bag, so the bag should be maintained regularly and the air pressure changes in the bag should be paid close attention to; water deashing will produce more foam, causing the sand settling tank to flow out, so the sand settling tank should be cleaned in time, and a watering design should be carried out to settle the foam; when the steam pressure decreases or the gear oil pump noise increases, the gear oil pump must be replaced.
When the burner is started, the fuel oil circulation system should be completed through the valve, and then the burner control box should be opened to start the burner. If the electronic ignition of the fuel oil fails, you can change the inlet tee and use the diesel engine for ignition. After the ignition is successful for 2 minutes, you can convert it into fuel oil. In this way, even the light fuel oil of lower quality can ensure combustion.

[1]. Composition of intermittent asphalt mixing plant
The intermittent asphalt mixing plant mainly consists of cold material silo, cold material distribution system, cold material conveying system, combustion and drying system, ventilation and dust removal system, hot material elevator, vibrating screen, hot material silo, powder conveying system and asphalt conveying system. System, metering system, mixing cylinder, control system, finished material transportation and storage system, asphalt heating and insulation system, etc.
2. Discussing the phenomenon of warehouse cascading in asphalt concrete mixing plants
2.1 First, let’s introduce the structure and principle of vibrating screen. The main components include: RetentionRubber, SupportTube, vibrating screen drive system and supporting electrical components
The working principle is introduced as follows: hot aggregate is sent to the vibrating screen through the hot aggregate elevator, and the hot aggregate is vibrated and screened by the vibrating screen. Stones of different specifications enter their corresponding hot aggregate bins through the screen and cannot pass through the geotechnical work. The super-sized particles from the cloth screen enter the overflow bin and are sent out.

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.

Asphalt mixing stations are constructed according to a certain process, which can not only ensure the construction quality, but also ensure that the asphalt mixing station is not damaged. Although construction details are critical, the key skills of asphalt mixing station construction must be mastered.
Before the construction of the asphalt mixing plant, the top surface of the asphalt mixing station construction range should be removed, and the site elevation should be kept dry and flat to meet the design requirements. If the surface is too soft, the foundation should be reinforced to prevent the construction machinery from losing stability and ensure that the pile frame is vertical.
Then the on-site construction machinery should be inspected to ensure that the machinery is intact and assembled and tested under the premise of meeting the requirements. To ensure the verticality of the asphalt mixing plant, the deviation of the gantry guide and the mixing shaft from the verticality of the ground shall not exceed 1.0%. Asphalt mixer manufacturer.

In order to keep the asphalt mixing plant in a stable operating process, a series of adverse factors related to it must be excluded. What should be paid attention to in this process?
First of all, the selection of the delivery pump in the asphalt mixing plant must meet the requirements of asphalt pouring per unit time during construction, height, and horizontal distance requirements. At the same time, there must be a certain technical and production capacity reserve, and the balanced production capacity is preferably 1.2 to 1.5 times.
Secondly, the movement and hydraulic systems of the asphalt mixing plant must be normal, and there must be no abnormal sound and vibration to avoid large aggregates and lumps inside the equipment, otherwise it is easy to get stuck at the feed inlet of the mixing plant or be blocked due to arching. Another point is that when the asphalt mixing plant is in the same site, it is not suitable to use too many pumps and pumps from multiple manufacturers to avoid affecting its normal operation.

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.

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.

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.

The quality of the asphalt mixing plant will be a key factor affecting the quality of the project. After reviewing relevant materials related to the production and construction of asphalt concrete, we summarized some cases of failures in asphalt concrete mixing stations during construction and analyzed the reasons.
1. Unstable output and low production efficiency of asphalt mixing plants
(1) Improper proportioning. The mix ratio of asphalt concrete is divided into target mix ratio and production mix ratio. Among them, the target mix ratio controls the cold material transportation ratio of sand and gravel materials, and the production mix ratio is the mixing ratio of various types of sand and stone materials in the finished asphalt concrete materials specified in the design. The production mix ratio is determined by the laboratory, which directly determines the off-site grading standard of the finished asphalt concrete. The target mix ratio is set to further ensure the production mix ratio, and can be adjusted appropriately during production according to the actual situation. When the target mix ratio or the production mix ratio is not appropriate, the stones stored in each measurement of the asphalt mixing station will be disproportionate, with some overflowing and some other materials, unable to be weighed in time, and the mixing cylinder will be idling, resulting in reduced output.

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.

The actual operation steps of drying drum of asphalt mixing equipment: 1. Pay attention to routine inspection; 2. Proper operation steps; 3. Effective maintenance.
Drying drum is a cylindrical device specially used for heating and drying stones in asphalt mixing equipment. Proper application and maintenance of drying drum can maximize the performance of drying drum, increase its service life and reduce application cost. Let’s take a look at the actual operation steps below.
1. Pay attention to routine inspections
The asphalt mixing equipment drying drum has been tested and inspected before leaving the factory, but it will be subjected to vibration and vibration during transportation to the construction site. A comprehensive inspection should be carried out before use: check whether all anchor bolts are tightened; whether all key pins are properly driven; whether all drive devices are adjusted according to the manufacturer’s instructions; whether all pipe connections are appropriate and whether the three-way joints are reliable; whether the entire equipment is fully lubricated; start the motor and check whether all parts can rotate steadily in the correct rotation direction; whether the pressure gauge can work normally and whether the valve is adjusted to the correct working pressure; whether the burner ignition mechanism is available and whether the gate valve is open.
2. Correct operation steps
After the equipment is started, it is recommended to control the machine manually at the beginning, and then switch to the automatic control mode after achieving the required production volume and pouring temperature. The stone should be dried and have a stable moisture content as much as possible so that the stone can maintain a stable final temperature when passing through the drying drum. If the stones delivered to the drying drum change frequently and the moisture content changes each time, the burner should be adjusted frequently to compensate for these changes.
The stones directly from the crushed stone have a relatively constant moisture content, while the stones from the outdoor storage yard have a higher moisture content, and the moisture content of different piles varies greatly. Therefore, it is best for the stones to come from the same source.

During the asphalt mixing process, we generally use complete sets of asphalt mixing plant equipment to carry out mixing operations. What are the benefits of using complete sets of equipment? Let’s take a look.
1. High efficiency
Complete sets of equipment can help improve production efficiency and ensure production quality.
2. Ensure quality
When mixing asphalt, a ratio will be set. For asphalt liquid used in different occasions, its ratio control has strict requirements. Only by ensuring its mixing method and mixing time can we ensure whether the asphalt liquid meets the production requirements. One of the benefits of using complete sets of equipment in the mixing station is that the quality can be effectively controlled.
3. Can be sampled
After the asphalt mixing plant is mixed, the relevant quality inspection personnel can conduct sample inspections to ensure that the mixed asphalt liquid meets the use requirements.
Using complete sets of equipment in the asphalt mixing plant can more conveniently control the mixing time and the order of feeding, and then effectively sample inspection, so as to ensure that the quality meets the construction requirements.

In today’s road construction, the use of a large number of road construction machinery represents the entry into the era of highway mechanization. For users, the goal is to use road construction machinery reasonably and tap its potential as much as possible. However, road construction machinery requires various accessories to work together. Now let’s take the asphalt mixing plant as an example to see what commonly used accessories and equipment are available.
Asphalt mixing plant equipment is a relatively complex system, which includes many equipment, mainly nine parts, namely: bag dust removal, finished material temporary storage warehouse, grading machine, fast heating asphalt tank, asphalt barrel removal machine, asphalt recycled material crushing and screening system, coal block crusher, coal mill and dust removal equipment, etc.

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.

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.

The quality of asphalt mixture directly determines the quality of asphalt pavement engineering. This article discusses the key points of supervision of ordinary highway asphalt plants in order to better monitor the quality of asphalt mixture.

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 damage avoidance mechanism in asphalt mixing plant
1. Asphalt operators should undergo physical examination. Anyone suffering from conjunctivitis, skin disease or allergic reaction to asphalt should not engage in asphalt work.
2. Asphalt operators must apply protective ointment on exposed parts of their skin, and a first aid kit should be provided on the construction site.
3. The factory uniforms and protective equipment of asphalt operators are stored in a centralized manner and are prohibited from being worn home or entering collective dormitories.
4. The transfer of lumpy asphalt should usually be carried out at night and on cloudy days, especially during hot seasons. Small machinery should be used for loading and unloading, and it should not be lifted and transported directly by hand.

Road construction machinery is a large range, so let’s talk about one of it, which is the asphalt mixing plant. It is mainly used to produce asphalt, so it is very important among road construction machinery and equipment. An important part, if the quality of the finished product is not good, it will greatly affect the quality of the road. Therefore, below, the editor will use the form of question and answer to guide you to continue learning.

Determining the material is a necessary stage in the design process of asphalt mixing equipment, and it is also one of the most critical links, because the material will be directly related to the use effect and service life of the entire equipment. Generally, when we determine the machine material, we usually base it on the characteristics of the working medium, and the same is certainly true for asphalt mixing equipment.