Some preparations for cement foaming agents before use
2019-04-02 17:01:08
First of all, carefully understand the use of cement foaming agents, fully understand the type of cement foaming agent, different types of foaming agents have different foaming power, foam stability is not the same, so there are limitations in the use process.
Secondly, carefully grasp the technical indicators of cement foaming agents, and measure the quality of foaming agents mainly include foaming power, foam toughness and bleeding volume. The foaming power reflects the foaming ability of the foaming liquid, and can be expressed by the foaming height and the foaming multiple. The higher the foaming height and the larger the foaming ratio, the stronger the foaming power of the foaming agent. Foam toughness is the characteristic that the foam does not break in the air for a specified period of time. The longer the half-time is, the smaller the subsidence time per unit time is, indicating that the foam has better toughness. The amount of bleeding refers to the volume of the aqueous foaming agent produced after the foam is destroyed. The foaming agent used for foaming products generally requires a foaming multiple of more than 20 times, a foaming settling distance of no more than 10 mm in 1 hour, and a bleeding volume of not more than 80 ml in 1 hour. Therefore, mastering the technical indicators of foaming agents can correctly select the use of cement foaming agents.
Finally, we must carefully understand the use of cement foaming agents. The foaming agents on the market generally have a large concentration. When used, they need to be diluted with a certain proportion of water to form a foaming liquid, and then foamed into foam. The concentration of the foaming liquid is closely related to the foaming effect. If the concentration is too high or too low, the foaming effect will be affected, and only a suitable concentration will result in a high quality foam.
Here we reminds everyone that when working, you should not be impatient: the foaming speed should be appropriate, too fast and too slow will affect the quality of the concrete; the generated hydrogen bubble diameter is small and evenly dispersed. In particular, the cement slurry is poured into the mold under the full volume state, and the dispersion is uniform to ensure the quality of the mold; the gas generation must not affect the condensation and solidification of the cement. If the cement is delayed, it will cause the cement strength to drop or the cement to condense abnormally.
