The knowledge of cement foaming machine

(The knowledge of cement foaming machine)

Cement foaming machine is a kind of equipment that mixes foaming agent and cement slurry to prepare foam concrete. Its working principle is to introduce air into the foaming agent aqueous solution and form foam through high-speed mixing, foaming and other processes. Then, these foam are mixed with cement slurry to prepare foam concrete.

The knowledge of cement foaming machine

Cement foaming machine and cement foaming agent are technical systems that cooperates and cannot function independently. No one can do without each other. Between the two, it cannot be said who is the main or who is not the main, but their role is quite equivalent. Without the cement foaming agent, the cement foaming machine will not produce foam and will lose its value of existence.

Similarly, without a foaming machine, no matter how good the foaming agent is, it cannot become a foam, and its use will be lost. The cement foaming machine adopts intelligent control, integrating a hydraulic system, quantitative feeding system, mixing system, automatic foaming system, and digital control system. The produced foam cement bubbles are fine and uniform, and the density can be continuously adjusted according to needs. Customers highly praise its technical performance and stability. In recent years, with the development, large cement foaming machines, also known as foam light soil operation stations, can be used for filling at the bridge head and back of expressway; Soft roadbed replacement; Widening of highways, etc. Fast speed and large daily completion quantity.

 

Principle and four methods for introducing gas into the foaming machine

Regardless of the type of cement foaming machine, the basic principle of being able to foam is to introduce the air into the foaming agent solution. The changes in various models are due to the different ways in which gas is introduced, resulting in different effects.

There are two necessary elements for the formation of foam: the first one is the foaming agent solution, and the other one is air, both of which are indispensable. The liquid film bordering the gas will certainly not develop without a frothing agent service, and there will be no bubbles.

In the foaming formation system, the foaming agent solution is a dispersion medium, and the gas is a dispersion phase. Only when the gas is dispersed in the liquid can bubbles be formed, and then countless bubbles form foam. Along with the substantial factor of lathering agent performance, the intro of gas right into the frothing agent remedy is the various other essential components. A foaming machine must complete the introduction of it into the liquid. Different foaming generators have different methods of introducing gas. Overall, there are several methods for introducing gas into foaming machines.

 

1) Slowly rotating blades introduce gas

It is a technique of directly presenting gas into mortar (or concrete slurry) mixed with lathering agents. When the mixer blades push the slurry, air enters the slurry with the mixer blades. Furthermore, a big quantity of air is wrapped in the slurry when the slurry is turned, and a section of the air is brought into the slurry by cement and accumulations. The amount of the 3 is the complete amount of air entering the slurry. Among them, the air brought into the slurry by the mixing blades and the air wrapped in the slurry by the turning blades represent the majority.After the air gets in the slurry, a liquid having frothing representative surfactants borders the air, developing a double electron layer fluid movie at the interface in between the air and the fluid, and inevitably creating bubbles in the slurry in a liquid to air way.As a result of the slow-moving turning speed of the blades and the introduction of less gas in this method, the amount of bubbles created is tiny, resulting in bad frothing effect and reduced effectiveness.

2) High speed rotating blades introduce gas

It is a method of introducing gas into the foaming agent solution through high-speed rotating blades. The introduction of gas mainly relies on the force of rotating blades. The blades of this model generally require high-speed rotation, with a speed greater than 700 rpm, typically between 700 and 1400 rpm. The circumferential speed at the end of the impeller should be>20m/s to achieve satisfactory results. A certain high speed is necessary to expose the impeller to the liquid, come into contact with air, and introduce air. The speed can not be too low. Otherwise, the impeller will not be exposed to the liquid, and the air intake will be really reduced. The appropriate rotational speed should be such that the impeller is exposed during liquid rotation.

The basic principle of impeller bleed is as follows:

When the impeller rotates at high speed, it drives the foaming agent solution inside the foaming cylinder to rotate, forming a rolling circular flow and generating a large vortex. At this point, the gas-liquid two-phase particles located at the gas-liquid interface at the top of the foaming agent solution will accompany each other and rapidly spiral down to the bottom of the vortex, forming a turbulent zone at 2.5-5 cm from the edge of the impeller. In this region, gas-liquid two-phase particles are subjected to strong shear and impact effects from the impeller, dispersing into small dispersions, quickly achieving gas-liquid mixing, evenly dispersing the gas in the liquid, and achieving the introduction of gas. The efficiency of its introduction is related to various technical factors such as rotational speed, impeller diameter, distance between the impeller and the foam cylinder, and the shape of the impeller blades. It is not determined by a single rotational speed. High speed impellers all have an air entrainment effect, but their efficiency, effectiveness, and energy consumption are different.

 

3) Pressure introduce gas

This is the most widely used advanced air entraining foaming method at home and abroad in 2021. It is also a more scientific air entraining method and is the core technology of high-pressure and medium pressure foaming machines for foam concrete.

Both technologies stated above are slow-moving, irregular, and have huge bubble diameters, especially the irrepressible bubble diameter, which is entirely according to the randomness of the foaming device and can not guarantee the two most important technological indicators of tiny bubble size and consistent foam.

In order to effectively solve these problems, the method of pressure induced foaming has emerged. Whether from the foaming amount, foaming speed, foam diameter, foam evenness, etc., they have reached a new level and made great technical progress. Its primary principle is to make use of different devices that can produce air pressure to press air right into the liquid stage and attain uniform mixing of both stages. Under normal pressure, it is difficult for air to enter a fluid, yet under a certain stress, it comes to be simpler. This atmospheric pressure not only presses the gas into the fluid but also the liquid into the gas, which is, in fact, a dual phase synchronized application of stress. By doing this, the blending of both stages will certainly be quick, effective, and consistent, and the bubbles will be small, satisfying the technical demands of foam.

There are mainly two types of pressure equipment used in China: one is an air compressor and the other is a blower. The air compressor produces high pressure, while the blower produces medium to low pressure. Therefore, the foaming effect of the air compressor is better, while the foaming effect of the blower is slightly worse. Those that use an air compressor for foaming are called high-pressure foaming machines, while those that use a blower for foaming are called medium and low pressure foaming machines. The quality of air compressor foaming mainly controls its pressure and exhaust volume, while the blower foaming mainly controls its air pressure and air volume.

Due to the good foaming effect of air compressors, most foaming machines in China use air compressors. There are also many applications of blower foaming in China, but compared to high-pressure foaming, this foaming method is still relatively rare. The foam produced by high-pressure air foaming has a low water penetration rate, small bubble diameter, fine and uniform, and high quality. The foam produced by air blowing is slightly larger in bubble diameter, and its overall quality is inferior to high-pressure foaming.

4) High pressure jet introduces gas

This is a foaming method that was attempted from 2015 to 2021 but has not yet been widely used. Its basic principle is to use the strong dispersion force generated by the jet to realize the instantaneous large surface contact between the gas phase and the liquid phase so that they can be evenly mixed and form foam with liquid wrapped gas. This method does not show any more advantages than high-pressure air foaming, and further exploration and improvement are needed.

 

Four methods for foaming machine selection

There is a wide variety of foaming devices appearing in the marketplace, with a growing number of foaming devices of numerous brand names, shapes, and names every day. Moreover, new brands and names of foaming machines will continue to increase. With so many models, many people are at a loss when choosing, even looking at it with confusion, not knowing how to make a choice, to the extent that they may even choose the wrong model or choose a model that does not meet technical requirements. In order to facilitate the correct selection of the foaming machine, the selection method is introduced below.

1) Fully understand the foaming principle of the foaming machine

This is the most important question to clarify when choosing a foaming machine. The foaming principle of each type of foaming machine is not entirely the same. Still, roughly speaking, there are several types of principles we discussed in the second section of this chapter, and their basic principles are mostly within this range, which can be compared and referenced.

Understanding the foaming principle of a foaming machine is of great help in further understanding its technical characteristics and performance. Different foaming principles have different equipment structures and performances. By understanding its foaming principle, one can have an overall grasp of this foaming machine and understand the overall direction of selection. This can determine that you won't make a big mistake when choosing. For example, you know that a certain model has high-speed impeller air entrainment. According to the principle we introduced earlier, you can preliminarily know that the foam produced by this foaming machine cannot be uniform in size.

Many foaming machine manufacturers treat the foaming principle as a technical secret, keeping inspectors unaware and habitually letting them see through the fog. In fact, it is completely unnecessary to keep it confidential. The foaming principle is not equivalent to being the structural secret of the foaming machine. Many people have learned about the foaming principle during inspection, and it is impossible to understand its entire structure. Therefore, it is entirely possible and necessary for the buyer to understand the foaming principle of the foaming machine during inspection without affecting the confidentiality of the core technology. This is not only responsible for the buyer but also for their own reputation.

 

2) Identify the type of foaming machine

No matter how many brands and names there are, in the final analysis, there are only three types of foaming machines: low-speed stirring type, high-speed impeller type, high-pressure, and medium-low type introduced earlier. The performance differences between different types of foaming machines are quite significant. Understanding its model categories is crucial for gaining a deeper understanding of its performance. Knowing the type of foaming machine, even if the manufacturer does not introduce its technical features (advantages, disadvantages, and scope of application), you can still have a clear understanding and understand it 60 to 70%. It is very important for accurately selecting the model.

3) Master some basic technical criteria of the frothing device

Recognizing the version is a detailed understanding, not a particular understanding. On this basis, one is required to even more understand numerous important technical criteria of the foaming equipment to determine whether it is appropriates for one's own manufacturing needs.

Return. Its output is the quantity of foam created, which has to be somewhat greater than its very own foam needed by 20% to leave the area. The foam production should be calculated based upon the complying with restrictions, not the upper limit;

Installed ability. To determine the versatility of one's electrical circuit to total power consumption;

Tools size. To identify the height and location of the workshop;

Foam diameter array. Normally, contrasts need to be made based upon the demands of one's very own item for bubble dimension;

4) Carefully recognize the frothing high quality and confirm that the utmost product of the frothing equipment is foam based on the field test.

The foam quality is the standard to evaluate the performance of the gathering device, and recognizing various other elements likewise serves this objective. If the high quality of foam is poor, what is using the foaming machine? To evaluate the foaming quality of the foaming device, we need to focus on complying with three elements: foam excellence, foam uniformity, and foam blood loss. Whether the foaming device can fulfill the demands of these three elements ought to be validated and verified via trial procedure.

 

How to maintain the foaming machine?

Regular inspection: Regularly inspect all components of the cement foaming machine to ensure they are intact and undamaged.

Maintain cleanliness: Regularly clean the cement foaming machine to prevent dirt accumulation.

Lubrication: Regularly lubricate the cement foaming machine to reduce friction and wear.

Maintenance of hydraulic system: The hydraulic system is the core part of the cement foaming machine, and it is necessary to regularly check the cleanliness of the hydraulic oil and the working status of the hydraulic components. If necessary, replace the hydraulic oil and hydraulic components in a timely manner.

Adjusting and maintaining the mixing system: The mixing system is an important part of the cement foaming machine, and it is necessary to regularly check the wear of the mixing blades. If necessary, replace the worn blades in a timely manner. At the same time, adjust the balance of the mixing shaft to avoid vibration and noise during the mixing process.

Check the air circuit system: The air circuit system is an auxiliary part of the cement foaming machine, and it is necessary to regularly check the sealing of the air circuit and the stability of the air pressure. If necessary, timely repair leaks and adjust the air pressure.

Maintenance of electrical system: The electrical system is the control part of the cement foaming machine. It is required to regularly check the working condition of electrical elements and the insulation of wires. If necessary, replace damaged electrical components and wires in a timely manner.

Keep records: After each maintenance, relevant maintenance data and problem descriptions should be recorded in a timely manner for future reference and troubleshooting.

 

Supplier

TRUNNANO is a supplier of CLC concrete with over 12 years experience in nano-building energy conservation and nanotechnology development. It accepts payment via Credit Card, T/T, West Union and Paypal. Trunnano will ship the goods to customers overseas through FedEx, DHL, by air, or by sea. If you are looking for high-quality concrete additives, please feel free to contact us and send an inquiry. (sales@cabr-concrete.com).

(The knowledge of cement foaming machine)