Electric concrete mixers: device, principle of operation,

Mechanization of construction and the use of machine labor allowed a person to achieve the results that modern civilization can boast of. In order to keep up with the general trend, we want to review the main characteristics of concrete mixing machines and find out what the electrical circuit of the concrete mixer is, what is its design and basic properties.

Concrete Mixers

Purpose

Virtually any modern construction does not do without the use of dry building mixtures from which materials such as concrete, masonry mortar, mortar for screed floors, plaster, etc. are prepared. To prepare these materials, they need to be shut with water in the correct proportion and mix thoroughly.

The quality and characteristics of the finished solution, whether it be concrete, plaster or masonry, directly depends on the efficiency of mixing the components of the building mixture. Concrete with medium and coarse aggregates depends most significantly on the proper distribution of ingredients during mixing, which is why the device is called a concrete mixer.

In addition, it is concreting that requires significant amounts of material, especially when building a foundation and pouring floor screeds.

Note! When concreting massive structures, such as foundations, work should be done in one go so that the structure is monolithic. This condition requires a certain speed of work, and hence the constant availability of ready-made concrete.

To provide the right amount of material prepared with your own hands and a shovel, you need a few people who will only be busy preparing and mixing concrete. If we calculate how much the work of these people will cost as a result, it can be concluded that the use of manual labor is simply unprofitable.

If you plan to work independently or with the help of one or two utility workers, then without a concrete mixer you simply cannot cope with concreting physically, since you will constantly have to be distracted by the preparation of a new portion of concrete. As a result, you will not have time to fill the entire volume in one shift and break the work technology.

In practice, work is most often carried out in parallel, and the mortar is constantly needed for various needs: concreting, brick laying, construction of screeds and reinforced belts, and plaster. Seasonality of work also does not allow to stretch construction activities, and therefore, without mechanization and the use of machines, your construction will last for many years.

Note! Concrete mixers are used to prepare mortars from dry mixes, water, and fillers required for the main activities and processes of modern construction: concreting, brick laying, plastering, finishing and others. The use of electric cars greatly simplifies, reduces the cost and speeds up construction.

Device and Variations

In order not to be mistaken when choosing and buying an instrument, one should understand its structure and principle of operation.

This is quite simple, because the machine consists of only six main nodes:

1. Support frame. This is the supporting structure to which the remaining nodes are attached. As a rule, it is made of steel and has a chassis to move the machine around the area;
2. Mixing drum. This is the tank in which the solution is mixed. Depending on the design of the machine, it can be movable or fixed, in the second case it has moving blades for mixing, it is made of steel or cast iron;
3. Electric motor for concrete mixer - this is a single-phase asynchronous electric machine operating on 50 Hz alternating current from a voltage source of 230 V. There are also more powerful three-phase electric motors for concrete mixers, but they are installed on professional equipment operating from 380 V network. The power of an ordinary household machine usually does not exceed 1 kW ;
4. The electrical circuit for starting and shutting down the unit, which consists of a push-button switch, capacitors and capacitors (depending on the motor connection scheme), sometimes there is a protective automatic. Electrical equipment must be reliably protected from ingress of debris, dust, water and other undesirable substances with a special casing, the conductors and contacts must be effectively isolated and hidden in the terminal blocks;
5. Mechanics to transfer torque from the motor shaft to the drum. There are gear and flange gear, the first is considered more efficient, but also more expensive. Often used chain or belt drive from the shaft to the rotating gear wheel;
6. The mechanism of tipping and fixing the drum with a movable head plate. It serves to unload the finished concrete, facilitates care and work.

By the principle of mixing devices are forced and gravitational type. The first type involves a stationary drum and rotating on the shaft of the blade, which mix the contents of the drum.

Gravity machines are equipped with a rotating drum with fixed blades welded to its inner wall. The mixture is captured by the blades and rises with the turn of the drum, and then it falls down under the action of gravity, while mixing.

For general construction needs, gravity machines are used, since they allow working with all types of mortars, including heavy concrete on coarse aggregates. In addition, they are more economical.

An important characteristic of a concrete mixer is the volume of its drum. There are models with a volume of 46 to 300 liters or more. For the repair of an apartment or house, the construction of small outbuildings, other activities of this magnitude, an aggregate of 50 to 100 liters is enough.

  Note! If you have a capital construction of a house, a summer house or a large garage, then you need to purchase a car for 100 - 150 liters. To ensure the work of a brigade of 5 or more people, it is better to look for a model with 200 liters or more.

Model selection criteria

So, we figured out the device and the varieties; now we can discuss the criteria for choosing a particular model when purchasing. As we found out earlier, we need a gravitational stirrer, that is, equipped with a rotating drum with fixed blades.

Next, you should determine the volume and capacity of the unit, since these indicators are interrelated. As a rule, the manufacturer finds the most optimal volume / power ratio, but of the two options with an equal volume, you should choose the one that is more powerful, since its resource will be higher.

We have already spoken about the choice of volume: 50-100 liters for the needs of repairs and small-scale construction, 100-150 liters for capital construction with a small brigade, 200 or more liters for capital construction with 5 or more people.

  Note! Particular attention should be paid to the quality of the materials used. The thickness of the steel on the walls of the drum should not be less than 1 mm, better - if it is 2 or more millimeters. There are models with thick-walled cast iron drums, they serve longer.

The frame should also be as strong as possible and consist of good steel of sufficient thickness. Pay attention to the quality of paint and anti-corrosion coatings. If the frame is equipped with a chassis, they must have a brake mechanism and be solid, because the tool is quite heavy.

  Note! The electrical part of the machine must be assembled in accordance with the norms of SNiP adopted for electrical work. A good car is distinguished by high-quality double insulation, reliable contact connection, the presence of closed terminal blocks and the use of copper conductors.

The electrical part must be securely covered with a protective cover that protects the circuit from moisture, water, dust, dirt and debris. In addition, such a casing prevents the operator from contacting the device's energized components.

  Note! Give preference to models with a minimum amount of plastic and thin-walled parts, in terms of construction strength and reliability - determining quality indicators.

If you look at how much an electric concrete mixer costs 46 liters, you can roughly imagine the volume of the minimum investment. As a rule, the amount starts from 5-6 thousand rubles and increases with the volume and capacity of the unit.

Making concrete is not cutting reinforced concrete with diamond circles and not diamond drilling holes in concrete, where tools are often rented because of its quality and cost, here rent is unrealistic because of the low resource of machines.

Conclusion

The use of an electric concrete mixer greatly simplifies, speeds up and reduces the cost of construction. In some cases, with large amounts of work, it is practically impossible to do without this unit.

The video in this article demonstrates the work of an electric mixer for concrete.