Nowadays, the quality of foamed concrete products is low, one of the reasons is that many people are lack of professional technical guidance and some wrong ideas.Concrete foaming agentis the key material in foamed concrete.
Misunderstanding 1: the smaller the pore size of the foam, the higher the strength of the foam concrete.
In terms of the same density and the same ratio, the small aperture undoubtedly reduces the density of bubble wall, and the foam concrete product bubble wall is the strength source, the higher the density, the higher the strength.According to our numerous experiments, the apparent strength is obviously higher by increasing the aperture size.Here, there is a point to be noted that the higher the strength is, the better the rigidity is, but the toughness is not as good as the small aperture foamed concrete.Another fact is that the strength of chemical foam is high, and the pore size of chemical foam is generally larger than that of physical foam, which is one of the reasons for the high strength.
Misunderstanding 2: Concrete foaming agent in the air stable bubble time long, in the slurry stability is good, the quality is reliable.
This is actually a mistake, for the same type of concrete foaming agent basically follow this rule, and different types of concrete foaming agent is not necessarily.At present on market foaming agent for concrete can say variety is various, use such method to detect its stability is not scientific.At present, there are mainly two kinds of testing the stability of foaming agent for concrete: one is to measure the stability of the foam by the half-elimination time in the air;The other is the foam in the air for a certain amount of time to discharge water.Either method measures stability in the air, and in fact the air stability of concrete foaming agent is not the same as the stability of slurry at all.The stability of foaming agent for concrete is significant only in slurry.In fact, some foaming agent for concrete that are very stable in air are not necessarily stable in slurry.Some foaming agent for concrete in the air can be as long as several days without breaking the bubble, but in the slurry performance is very general, and can not be stable production of low-density concrete foam products.
On the contrary, some foaming agent for concrete with poor stability in the air are extremely stable in the slurry and can easily produce low-density foamed concrete products. The reason why this is the case is mainly due to the different environment. In the air, there are two kinds of interfacial materials, while in the slurry, there are three kinds of interfacial materials.
In fact, the stability in the air is mainly to see the solid content, solid content of high stability is relatively good, and the solid content should not be the index to measure the performance of foaming agent for concrete.For cement blowing agent, we should pursue the stability in slurry.
Misunderstanding 3: Concrete foaming agent determines the size of foam aperture.
Often have a customer ask concrete foaming agent bubble small?When I ask him "why do you need a concrete foaming agent with tiny foam?" most people fall back on the first myth.In fact, the size of the aperture is mainly related to the foaming machine, a good cement foaming machine can produce a small aperture foam.With the same concrete foaming agent, the smaller the pore size, the more stable the foam.That is, pore size is small precisely in order to make up for concrete foaming agent stability is not good enough defects.In other words, if the foam pore size is large, the foam stability can be good enough, no bubbles, no combined bubbles, concrete foaming agent stability is good.Of course, the size of the foam is not said to have nothing to do with concrete foaming agent, cement foaming agent stability requirements are not high in the field, you can choose the stability is not too ideal foaming agent, but can form a combined bubble, combined bubble nature than not combined bubble.
Misunderstanding four: compound cement blowing agent is good blowing agent.
As a result of the ambiguous to compound concrete foaming agent definition, a lot of manufacturer propagandize compound concrete foaming agent and did not follow the principle that mix, and it is simple and optional mix and become, such compound cement blowing agent how is good blowing agent?The reason for such publicity, the reason is that the real compound concrete foaming agent is really superior to a single component of cement blowing agent performance, and some people say compound cement blowing agent for the fourth generation of Concrete foaming agent, so that everyone has followed suit.
Misunderstanding five: Concrete foaming agent stability, foaming force is high.
Concrete foaming agent stability and foaming power is contradictory, want to have good foaming power, the same situation, you must sacrifice its stability, on the contrary, good stability, you have to sacrifice its foaming power.Have manufacturers to publicize their foaming agent foaming force, stability is better, basically belong to false propaganda.Concrete foaming agent should have different model.There is good stability, there is a high foaming force, there is a more balanced foaming force and stability is not outstanding.
So, should be based on different application fields, choose the appropriate concrete foaming agent, such as roof insulation on the selection of foaming force Concrete foaming agent, because roof insulation pouring height is low, the stability of concrete foaming agent is relatively low.In a word, concrete foaming agent is easy to bubble, but also easy to break the bubble (poor stability), difficult to bubble, the foam is not easy to break the bubble (good stability).
There are still many mistakes of concrete foaming agent, I hope this article can bring some benefits to you, get out of the mistakes as soon as possible, grow together, let the whole industry into a healthy and orderly development, let the foam concrete really become a good material of building energy conservation.