Home » Products » Bitumen Processing » Basic principles and process flow of asphalt mixing equipment

Basic principles and process flow of asphalt mixing equipment

Asphalt mixture mixing equipment is a factory-style complete set of equipment that mixes dry and heated aggregates of different particle sizes, fillers and asphalt according to the designed mix ratio at a specified temperature into a uniform mixture. It is widely used in high-grade highways and urban roads. , airports, docks, parking lots and other engineering construction. It is a key equipment for asphalt pavement construction, and its performance directly affects the quality of asphalt pavement.
Generally, there are two types of asphalt concrete mixing equipment: intermittent type and continuous type. The continuous process flow is simple and the equipment is simplified. As for the intermittent forced mixing equipment, due to the secondary screening of aggregates, various components are measured in batches, and forced stirring and mixing can reliably ensure gradation, and the measurement of powder and asphalt can also achieve very high accuracy; so the mixing equipment The asphalt mixture produced is of high quality and can meet various construction requirements.

Rated 4.8/5 based on 516 customer reviews
Share:
Content

Asphalt mixture mixing equipment is a factory-style complete set of equipment that mixes dry and heated aggregates of different particle sizes, fillers and asphalt according to the designed mix ratio at a specified temperature into a uniform mixture. It is widely used in high-grade highways and urban roads , airports, docks, parking lots and other engineering construction. It is a key equipment for asphalt pavement construction, and its performance directly affects the quality of asphalt pavement.
Generally, there are two types of asphalt concrete mixing equipment: intermittent type and continuous type. The continuous process flow is simple and the equipment is simplified. As for the intermittent forced mixing equipment, due to the secondary screening of aggregates, various components are measured in batches, and forced stirring and mixing can reliably ensure gradation, and the measurement of powder and asphalt can also achieve very high accuracy; so the mixing equipment The asphalt mixture produced is of high quality and can meet various construction requirements.
Since my country currently mainly uses forced intermittent asphalt mixing equipment, the following content is mainly based on Sany Heavy Industry’s LB series asphalt mixing equipment as a representative. 1. Mechanical system process flow
The main process characteristics of the intermittent asphalt mixture mixing equipment are: various ingredients are measured in batches, and are put into the mixer in a pre-set order for forced mixing. After the mixed finished materials are discharged, the next cycle is carried out to form A cycle of work that starts over and over again. The so-called intermittent type refers to the mode in which the dresser measures and stirs production in batches.
Use a loader to shovel sand and gravel materials of different specifications into the corresponding cold silos; after volume measurement of the belt feeder controlled by the frequency converter (the frequency converter parameters are preset according to the grading type, output and mix ratio), Material belt conveyor and feeding belt conveyor transport it to the drying drum.
The drying drum uses countercurrent heating to dry and heat the sand and gravel to a certain temperature (the control system automatically adjusts the flame size of the burner). Due to the rotation of the drum, the sand and gravel are repeatedly lifted and dropped by the blades in the drum, forming a material curtain. , which enhances the heat exchange effect, and with the help of the inclination of the drum, the sand and gravel materials continue to move forward while being heated; after coming out of the drum outlet, together with the coarse powder collected by the gravity dust collector, they are lifted up and unloaded by the hot aggregate elevator. into the hot aggregate screening machine.
The high-temperature dusty flue gas discharged from the drying drum first enters the gravity dust collector for preliminary purification through the first-level flue. The collected powder with a particle size of 0.075mm or more is sent to the entrance of the hot aggregate elevator by a screw conveyor; The dust and flue gas enter the bag dust collector, and the filtered flue gas is directly discharged into the atmosphere by the induced draft fan. The dust recovered from the bag dust collector is sent to the recycled powder supply system by a screw conveyor for storage.
The hot aggregate is screened into several specifications through a screening machine, and then flows into corresponding hot material storage silos for storage. According to the set ratio, aggregates of different specifications are put into the stone measurement bin in batches in order of small and then large for cumulative measurement; at the same time, the hot asphalt sent from the asphalt supply system and the powder sent from the powder supply system are separately Put it into the respective measuring device for measurement according to the set ratio. After weighing is completed, put it into the mixing pot according to the preset order for forced stirring. The mixed finished product materials are unloaded into the finished product lifting trolley, and then lifted by the winch and unloaded into the finished product silo for storage. You can also choose to unload them directly into the material transport dump truck.
The control system relies on the signals detected by each sensor to monitor important parameters such as material ratio, asphalt content, and mix temperature in real time to ensure that the quality of the mix produced can meet the user’s requirements. Throughout the process, the electronic control system is also equipped with interlocking protection devices to protect the equipment from unexpected mechanical accidents.
It should be noted that the volume measurement of cold aggregate passing through the belt feeder is pre-measurement, and the measurement of screened hot aggregate, powder and hot asphalt is measurement. Because of the secondary measurement, it can ensure the gradation of the mixture and the proportion of aggregate, powder and asphalt with relatively high precision. The current static metering accuracy for aggregates and powders does not exceed ±0.5%, and the static metering accuracy for asphalt does not exceed ±0.25%. Since it is intermittent mixing, it is also very convenient to change the mixture ratio, and the formula can be changed or replaced without stopping the machine.

Inquiry


    More Road Maintenance

    Emulsified modified asphalt equipment is classified according to the production process and can be divided into three types: intermittent emulsified modified asphalt equipment, semi-continuous emulsified modified asphalt equipment, and continuous emulsified modified asphalt equipment. During the production of emulsified modified asphalt equipment, demulsifier, acid, water, and latex modified materials are blended in a soap mixing tank, and then pumped into the asphalt into the colloid mill. After a can of soap is used up, the soap is redispensed, and then the production of the next can is completed.
    The emulsified modified asphalt equipment mentioned here includes hot water pumps and circulation pumps. This type of centrifugal water pump generally uses a pipeline centrifugal pump. There is a sewage outlet at the bottom of the pipeline centrifugal pump. Pay attention to the sewage outlet at the bottom of the emulsified modified asphalt equipment pump. The water in the water tank is released through the filter valve. Some emulsified modified asphalt equipment does not have a filter valve to save equipment costs, so it can only be emptied by loosening the flange bolts at the bottom. There are basically two methods of moisturizing emulsion pumps for emulsified modified asphalt equipment on the market, gear oil pumps or centrifugal water pumps. The gear oil pump can only drain the liquid in the pump through the connecting flange of the pipeline. The centrifugal water pump carries out sewage treatment through its own sewage outlet.
    When used in the production of emulsified modified asphalt equipment, depending on the modified material technology, the latex pipeline can be connected in front of the colloid mill or behind the colloid mill, or there may be no latex pipeline and it must be made manually. Add the required amount of latex into the soap jar.

    Water is one of the raw materials of the modified asphalt storage tank, and it is distributed in various components of the modified asphalt storage tank equipment. According to the components where water is distributed, the anti-cold measures are explained one by one. The water tank of the modified asphalt storage tank, the water inside the water tank is released through the filter valve. Some instruments of the modified asphalt storage tank do not have a filter valve to save the cost of the equipment. The modified asphalt storage tank can only be drained by loosening the flange bolts at the bottom. The water pump of the modified asphalt storage tank mentioned here includes a hot water pump and a circulating water pump. This type of water pump for the modified asphalt storage tank generally uses a pipeline centrifugal pump. There is a sewage outlet at the bottom of the pipeline centrifugal pump. The modified asphalt storage tank pays attention to the sewage treatment of the sewage outlet at the bottom of the pump. The modified asphalt storage tank emulsion tank generally uses a cone bottom. However, in order to better process the modified asphalt storage tank coefficient, the inlet and outlet are usually not placed at the bottom of the modified asphalt storage tank. Emulsion (mostly water) will remain at the bottom of the tank, and this part of the residual liquid in the modified asphalt storage tank must be discharged through the filter valve at the bottom. Emulsion pump for modified asphalt storage tank There are basically two types of emulsion pumps for modified asphalt storage tank equipment on the market, gear pumps or centrifugal water pumps. Gear pumps can only discharge the liquid inside the pump through the connection flange of the pipeline. The centrifugal water pump for modified asphalt storage tanks uses its own sewage outlet for sewage treatment. The first four items of modified asphalt storage tanks with basic knowledge are basically discharged, and the modified asphalt storage tanks will focus on the latter types. Modified asphalt storage tank colloid mill There will also be residual emulsion or water inside the modified asphalt storage tank colloid mill. The gap between the stator and rotor of the colloid mill is within 1mm. If there is a little residual water in the modified asphalt storage tank, it will cause the accident of frozen modified asphalt storage tank. The residue in the colloid mill can be treated by loosening the connection bolts of the finished product pipeline.

    We need to prepare a lot of work when using modified asphalt equipment. What kind of work do we need to prepare? Next, let me briefly introduce the relevant knowledge points.
    1. Heat transfer oil heats and insulates the modified asphalt equipment and nozzle. After spraying, the asphalt pump and nozzle do not need to be cleaned with diesel. Use high-pressure air to press the asphalt in the pipeline and spray pipe back to the tank, and then blow the nozzle; use heat transfer oil to keep warm, so that the pipeline and nozzle are smooth and unobstructed. 2. Various asphalts can be spread: high-viscosity asphalt, hot asphalt, emulsified asphalt, etc.; the spreading width can be freely adjusted, each nozzle can be controlled separately, and the maximum spraying width is up to 6m. Flexible handheld spray guns can be used to spray asphalt on corners. 3. Excellent thermal insulation performance, average cooling ≤1-2℃/h. 4. Convenient loading and unloading function. In addition to filling asphalt from the asphalt tank port, hot asphalt can be sucked out by itself, and external asphalt can also be pumped and transferred. 5. The modified asphalt equipment is evenly spread, and the nozzle design can be used for triple overlapping spraying.
    The above are the relevant knowledge points of modified asphalt equipment. I hope the above content can be helpful to everyone. Thank you for your viewing and support. More information will be sorted out for you later. Please pay attention to our website updates.

    In modern highway maintenance work, how to repair asphalt pavement quickly and effectively has become one of the key issues. As an advanced repair technology, cold patching technology is very popular because of its convenient construction and remarkable effects.
    What is the cold patching process?
    Cold patching process, as the name suggests, refers to a technical method for repairing asphalt pavement without heating. This process uses a specially proportioned cold-patch asphalt mixture. This material can maintain good fluidity and adhesion even at lower temperatures, thus ensuring the quality of the repair.
    Advantages of cold patching process
    Fast construction: Cold patching materials can be directly applied to damaged areas without preheating, and are immediately open to traffic, greatly shortening repair time.
    All-weather construction: Whether in hot summer or cold winter, cold patching materials can be effectively constructed and are not affected by the weather.
    Easy to operate: Thanks to its good working properties, even small damaged areas can be repaired easily.
    Environmentally friendly: The construction process reduces environmental pollution and is in line with the concept of green construction.
    Application scenarios
    The cold patching process is suitable for various types of pavement repair work, especially those places where traffic needs to be restored quickly, such as urban main roads, highway ramps, etc. In addition, the cold patching process is also an ideal choice for remote areas or situations where professional heating equipment is lacking.
    In short, the cold patching process has occupied a place in the field of rapid repair of asphalt pavement with its unique advantages and has become an indispensable part of modern highway maintenance.

    Asphalt spreader is an irreplaceable tool for highway maintenance. Asphalt spreader is an irreplaceable tool for highway maintenance. Highway maintenance is divided into four categories according to the nature of the project, scale, and technical complexity: minor repair, medium repair, major repair, and improvement. Specific classification:
    (1) Minor repair and maintenance project: preventive maintenance and repair of slightly damaged parts of the highway and all its engineering facilities to keep them in good condition. It is usually planned and carried out daily by the maintenance team within the annual minor repair and maintenance quota funds on a monthly (ten-day) basis.
    (2) Medium repair project: regular repair and reinforcement of general wear and tear and local damage of highway engineering facilities to restore them to their original state. It is usually planned and implemented by grassroots road maintenance agencies on an annual (seasonal) basis.
    (3) Major repair project: periodic comprehensive repair of major damage to highway facilities to fully restore them to the original design standards, or local improvements and individual additions within the original technical level to gradually improve the highway’s traffic capacity. It is usually organized and implemented by grassroots road maintenance agencies or with the help of their superior agencies according to the approved annual project budget.
    (4) Improvement projects are large projects that improve the technical level of roads and their engineering facilities in stages and sections due to their inability to meet traffic volume and load requirements, or significantly improve traffic capacity through improvements. It is usually organized and implemented or completed through bidding by regional road maintenance agencies or provincial road maintenance agencies according to the approved plan and design budget. As a manufacturer of asphalt spreaders, we welcome you to visit us.