Foam generator for foam concrete: an overview of production

The foam generator is necessary for the production of the so-called building “cellular” type of concrete: various modern types of building materials are produced from it for the needs of private and industrial construction. Such materials as foam silicate, foamed gypsum, foam concrete, as well as well-known polystyrene foam concrete are used throughout the construction industry.

Many craftsmen make foam generator for foam concrete with their own hands, and if the goal is volumetric production, then it is advisable to purchase a factory one.

The composition of the materials under consideration includes various polymer additives, but basically their materials consist of concrete, but not ordinary concrete, but foamed by a special method using foam generators.

As you know, currently produced materials from cellular concrete have enhanced performance characteristics. To the predominant physico-technical characteristics of cellular concrete can be safely attributed to noise and heat insulation.

These concretes have increased resistance to water absorption and perfectly tolerate low temperature conditions.

The highly dispersed air-concrete foam formed by the foam generating installations allows the formation of a material with an air mass content of up to 80%.

These indicators give cellular concrete all the properties described above. In addition, it should be noted another advantage of these concretes, namely, low weight, which allows to significantly save time and effort during the construction of buildings.

It should be noted that the quality of the concrete forced by foam generators directly depends on the equipment itself, its correct settings, and on compliance with the technology of the entire process during production.

Foam generators are designed for the production of cellular concrete, and how effectively they perform their direct functions, depends on the final profit from the sale of the original manufactured product.

On a note! Single-stage cavitation mixers do not provide such an effect as good foam heater devices, which allow a lot to reduce the density of cellular concrete, without losing the strength characteristics. And thus help to reduce the cost of the original product and reduce the cost of production of foam-gas and polystyrene foam concrete.

The use of the foam generator makes it possible to position:

• gypsum,
• cement-sand,
• cement,
• lime-cement mixtures -

to the required content in the composition of the air mass, allowing to form at the exit of the production line products of the required quality.

Moreover, the process of porisation can be adjusted completely arbitrarily by adjusting and adjusting the equipment, thereby achieving the necessary quality characteristics of the material.

Methods for the production of foam concrete

Single-stage production

This scheme provides for the production without the use of foam generating installations; all mixing processes take place in special bar mixers in an upright position. With this method, the process of mixing and foaming occurs by adding to the mixing neck a special component - a foam converter.

The entire initial mass in a bar mixer is mixed at sufficient revolutions of the shaft at about 200–500 rpm. It should be noted that this method of production is most likely not the most technologically advanced.

Two-stage production

Just in this way a foam generator is used. The process itself takes place according to the scheme of horizontal mixing and foaming. Note that the speed of the shaft with this method is much lower - up to about 50 rpm. despite the fact that the quality of the original product is higher.

The structure formation of the entire mixture in horizontal mixers allows the foam generator to make better adjustments to the process of porisation of ingredients. Entering into the mixture exactly the amount of foaming agent, which is required for a particular material, it is possible at the output of the production line to obtain a material of desired density.

A good foam generator allows you to create a fine and fairly dense foam. The optimal size of air bubbles is about 0.1–0.4 mm. On a single-stage mixer there is almost impossible to get such a high-tech foam as in a two-stage system.

On a note! Technological foam generator can easily save the foaming agent. Average consumption is about 0.4–0.7 l / m3. The recommended average foaming agent consumption should not exceed 0.6–1.6 l / 1 cubic meter. produced cellular concrete. With a large amount of foaming agent, the period of hardening and setting of the mixed, porous mass significantly increases. Also, the strength and shrinkage characteristics of the finished product can be significantly reduced.

Characteristics of foam generator installations

The following types of foam generators are currently produced:

• Reversible cyclically operated foam generating sets (irrelevant today due to its non-manufacturability).
• Continuous Operation Devices (more advanced devices relevant today and find their practical application everywhere).

Purpose of installations for the porisation of cellular concrete

• Installations for the porisation of concrete perform their direct function - they generate an air phase in the mixture until the whole mass is homogeneous.
• The installation for the porisation of concrete must meet the following requirements and provide:
• Uninterrupted supply of foam mass directly to all types of mixing parts of the system.
• It is desirable that the device be adapted to all types of both domestic and foreign frothers.
• The device should work through the volume of foam at an average speed of at least 300–500 l / min. or about 6–9 l / sec.
• The performance of the equipment should be determined and strictly correspond to the required production capacity, it is desirable to choose devices with a margin of productivity. For example, per 1 m3 of foam concrete material with density characteristics of about 800–900 kg / cu. m. require an average of about 400-500 l / foam mass.

The average time for obtaining such a volume of foam starts from 1–5 minutes. and depends on the power of the foam generator. The amount of frother required to obtain 500 l / foam is about 20 l. Based on the average calculation, the appropriate type of foam generator is selected.

Foamer DIY

As for the self-made generator, to build it, you must have the appropriate knowledge and skills.

To build a homemade device will need:

• raw materials;
• detailed instructions;
• drawings and detail diagrams;
• as well as special equipment for boring, grinding and fitting of individual units of the unit.

Otherwise, if the calculation is incorrect, the equipment will work inefficiently or will not function at all.

To the note: The cutting of reinforced concrete with diamond circles, as well as diamond drilling of holes in concrete is carried out with the help of special equipment with nozzles having high-strength surface spraying. As soon as the spraying abrades during operation of the nozzle, it is re-sprayed with a special method or replaced with a new nozzle.

If you have the necessary engineering knowledge in this field, raw materials and machines for metal boring, then all that remains is to find the appropriate device diagrams and proceed to its production.

In any case, if you plan to use the device on an ongoing basis with increased load, it is more expedient to purchase a factory perfect assembly of the model of the device. In the future, all the costs of purchasing the device will pay off at times.

And given that the manufacturer gives a guarantee for the failure-free operation of the device during a certain time period, then all the risks associated with its acquisition are practically reduced to zero.

You can see how the homemade foam generator works in the video in this article.