Technical characteristics of plug valves in asphalt mixing plants

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 mixing plants are highly professional equipment with complex systems. It is inevitable that some failures will occur during use. So, what are the common hardware failures of asphalt mixing plants? Do you know?
(I) Because its system is relatively complex, when different components have problems, the problems caused may be different. If during the operation, it is found that the material addition of each silo is inaccurate, this problem may be due to the failure of the sensor of the asphalt mixing plant. At this time, the machine should be stopped for inspection and replaced with a new sensor if necessary. It may also be caused by the jamming of the scale bar. At this time, foreign objects should be removed in time.

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.

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.

The mixing speed of asphalt mixing plant equipment is indeed very fast, and the corresponding mixing power must be very high, but the specific amount must be measured in a certain way to determine the scope of use of asphalt mixing equipment. There are many methods to measure the mixing power of asphalt mixing equipment, but the relatively small errors are the motor counter-torque measurement method and the strain measurement method.
When the motor of the asphalt mixing equipment starts running, the electromagnetic moment acting on the motor rotor and the electromagnetic moment acting on the motor stator are equal, but their directions are opposite. Therefore, as long as the torque acting on the stator is measured, the torque on the rotor can be obtained, and the actual mixing torque is obtained after deducting the friction torque on the rotor bearing.
On the premise of knowing the torque and mixing speed, the mixing power of the asphalt mixing equipment can be calculated. This is the so-called motor counter-torque measurement method, which is relatively simple and suitable for smaller mixing systems.

There is also a reversing valve in the asphalt mixing plant, which generally does not cause problems, so I have not understood its solutions in detail before. But in actual use, we encountered this kind of failure. How should we deal with it?
The failure of the reversing valve of the asphalt mixing station is not complicated, that is, the reversing is not timely, gas leakage, electromagnetic pilot valve failure, etc. The corresponding causes and solutions are of course different. For the reversing valve to not change direction in time, it is generally caused by poor lubrication, the spring is stuck or damaged, oil dirt or impurities get stuck in the sliding part, etc. For this, it is necessary to check the status of the lubricator and the quality of the lubricating oil. Viscosity, if necessary, the lubricant or other parts can be replaced.
After long-term use, the reversing valve is prone to wear of the valve core sealing ring, damage to the valve stem and valve seat, resulting in gas leakage in the valve. At this time, the sealing ring, valve stem and valve seat should be replaced, or the reversing valve should be replaced directly. In order to reduce the failure rate of asphalt mixers, maintenance must be strengthened on a daily basis.

Asphalt mixing equipment is also divided into fixed and mobile types. There are still big differences between the two to a certain extent. Let’s take a look at the design of mobile asphalt mixing equipment. What advantages can bring to the equipment?

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.

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.

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.

The asphalt mixing plant is constructed according to a certain process, which can not only ensure the construction quality, but also ensure that the asphalt mixing plant is not damaged. Although the construction details are critical, the key skills of the asphalt mixing plant construction must be mastered.
Before the construction of the asphalt mixing plant, the top surface of the asphalt mixing plant construction range should be removed, and the dry and flat site elevation should be kept to meet the design requirements. If the ground surface is too soft, the foundation should be reinforced to prevent the construction machinery from becoming unstable and to ensure that the pile frame is vertical.

In the 21st century, with the booming development of modern engineering construction, complex integrated supporting equipment has been invested in large quantities. Its complex process and more independent operating components have relatively high requirements for the performance of its equipment control system. The application of PLC in asphalt mixing station realizes the control of the entire process of asphalt mixing station, which facilitates the construction of modern engineering construction. Therefore, this article discusses and analyzes the application of PLC in asphalt mixing station, which has certain economic value and practical significance.

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.

1: The site should be located on higher ground and away from residential areas and densely populated areas.
2: The venue should consider the transportation distance and choose a location with convenient transportation.
3: Determine the website construction plan according to the terrain

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.

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

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.

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:

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.

Asphalt mixing plant equipment is mainly composed of batching system, drying system, ignition system, hot material lifting, vibrating screen, hot material storage bin, weighing mixing system, asphalt supply system, granular material supply system, dust removal system, finished product hopper and automatic control system.
Components:
⑴ Grading machine
⑵ Vibrating screen
⑶ Belt vibrating feeder
⑷ Granular material belt conveyor
⑸ Drying mixing drum;
⑹ Coal powder burner
⑺ Dust removal equipment
⑻ Bucket elevator
⑼ Finished product hopper
⑽ Asphalt supply system;
⑾ Distribution station
⑿ Automatic control system.

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.

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.

The drive unit is one of the important components of the asphalt mixing plant, so whether it can be reliably operated must be highly valued to avoid adverse effects on the entire asphalt mixing plant. To ensure that the drive unit in the asphalt mixing plant is indeed complete and reliable, the following maintenance measures are essential.
The first thing to pay attention to is the universal rotating part of the drive unit of the asphalt mixing plant. This part has always been a fault-prone part. In order to reduce the occurrence of faults, grease should be added on time, and the wear should be checked frequently, and repaired and replaced in time. Users should also prepare the universal shaft assembly to avoid affecting the working process of the entire asphalt mixer.

Asphalt mixing plants are large-scale products with high professional and technical requirements, and are composed of multiple systems. Among them, asphalt tanks are also a very critical part. Whether it is manufacturing, debugging or installation, it needs to be operated according to the actual application needs of users.
In addition to the manufacturing, debugging and installation, which need to be operated by installers, the maintenance of asphalt tanks in asphalt mixing plants must also be managed by professionals. At the same time, they must strictly follow all safety rules to operate. Before operation, they must be proficient in the relevant requirements and based on the regulations and safety instructions for storing and handling hot asphalt.

Mechanism to avoid asphalt damage 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.

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.

Asphalt mixing plant is a relatively important complete set of equipment in people’s lives. There are many components of this equipment, such as grading machine, vibrating screen, belt feeder, powder conveyor, elevator and other parts. Plug valve is one of them, so what is the specific role of plug valve in asphalt mixing plant? This article will give a brief introduction.
The plug valve is first of all a closure or plunger-shaped rotary valve. Generally, it is necessary to rotate 90 degrees to make the channel opening on the valve plug the same as that on the valve body, or to split it to play the role of opening or closing. The shape of the plug valve in the asphalt mixing plant is generally cylindrical or conical.

Asphalt mixing equipment is equipment used to produce asphalt concrete in large quantities. Because this equipment is affected by various factors during the production process, some problems will inevitably occur after a period of use. Sinoroader Group The editor of the asphalt mixing equipment company of China Machinery Co., Ltd. will introduce to you the methods of rescuing damaged parts in asphalt mixing equipment.
Asphalt mixing equipment encounters different problems, and the solutions are also different. For example, one of the common problems of asphalt mixing equipment is that parts are worn out and damaged. The solution that needs to be done at this time is to start from the production of parts. Just start improving.