The main problem with the operation of the concrete mixer is the selection of the correct proportions of the concrete mix. Today, there are many recipes for how to prepare the solution with your own hands, but it must be understood that there is no universal recipe. This is due to the fact that different concrete must be used for different purposes. But the components with which the solution is prepared are permanent. These are sand, water, cement and crushed stone. In some cases, special additives are used.
Kneading cement in a concrete mixer is much easier and faster than manually.
Preparation of the solution
The brand of concrete solution produced depends on the cement mix to be used and in what proportions it will be added. In most cases, used cement brand M400 or M500. For example, in order to obtain a high-quality concrete mortar using cement grade M400, 2 gravel measures, 8 gravel measures, 4 sand measures and 1 water measure should be put.
Table of proportions of the components of a concrete solution.
This ratio of ingredients is optimal and allows you to get at the exit of concrete having the mark M250. If the same ratio of initial elements will be applied with the 500th cement, then concrete mix M350 will be obtained.
When mixing the solution in a concrete mixer should pay attention to its loading. In no case should not be allowed to overload in the mixer. The permissible amount of load is determined by the capacity of the drum, which will necessarily be indicated in the technical passport of the unit. Overloading will not allow high-quality kneading of the solution in the mixer, moreover, it will work at peak loads, which can lead to failure of the electric motor or breakage of the drive shaft.
All ingredients must be added in strict sequence:
- Crushed stone
In this case, the solution should be stirred until a homogeneous mixture. This extends to its color and consistency. When these parameters are normal, the solution is ready for use.Back to table of contents
Some features when working with a mixer
Table of cement consumption.
When working with concrete mixers, there are several basic rules that will make their work more productive and efficient. Moreover, compliance with these rules will help to increase the life of the equipment.
The first and most important rule is the presence of a flat horizontal surface on which a concrete mixer will be installed. Before you start downloading all the components, you must install the unit exactly. To achieve this, you can use the wooden inserts under the legs of the agitator. The presence of even a small angle during installation can lead to poor-quality concrete. Moreover, the concrete mixer will soon fail. It is especially important to follow this rule when using machines with a forced action.
The second rule, but no less important, is to respect the mixing time. In the case when the forced action apparatus is used, its operation time will be 2-3 minutes. In gravity units, it will be 5-6 minutes. If the time is increased, it will evaporate the required amount of water, which will cause a decrease in the elasticity of the mixture. It should be remembered that the filling of all components into the drum and the unloading of the finished composition should be carried out only when it rotates.
The proportions of cement M-400 and M-500.
Testing the readiness of concrete is carried out by taking a small sample of it. To do this, cast it in a trough or on an iron sheet. After that, with the help of a shovel shovel, notches are made on the mixture obtained. If these notches fall off, the concrete can be considered ready. Otherwise, you need to send the sample back into the mixer and bring the composition to readiness.
In preparing the concrete composition, it is necessary to take into account the fact that a certain amount of it will stick on the blades and the surface of the drum. This will lead to a decrease in the yield of the finished solution. Therefore, making the first batch, it is necessary to increase the amount of the original ingredients by 10%. To reduce the adhesion of the mixture, the blades can be treated with waste oil. It will perform a layer between the concrete and the parts of the unit.
After completion of the work should always be washing the apparatus. To do this, pour into the drum 2-3 buckets of water and mix it. Thus, the water will wash all the dirt that has remained on the internal elements of the apparatus. If such a process is neglected, then all the original elements will harden and then they will have to be chipped off. This is a very time-consuming process, the more it can lead to equipment damage.
Compliance with all these rules will allow not only to understand how to prepare the solution, but also how to do it qualitatively. Moreover, it will help to properly operate the mixer, which will increase its service life and improve the quality of the resulting composition.