The foam quality of the foam device of the polyurethane foam machine is the only criterion to judge the performance of the foam system, that is, the foam fineness, foam uniformity and foam bleeding water. Whether the foaming machine can meet the requirements in these three aspects should be confirmed through the test machine.

The foam produced must be fine and dense, and the size of foam has a great impact on the quality of foam solidified soil, mainly including the following points.

1. The smaller the bubble diameter, the higher the strength of foamed concrete; The larger the bubble diameter, the lower the strength of foamed concrete. The bubble diameter is inversely proportional to the strength.

2. The larger the foam is, the more connected holes are, the higher the water absorption rate is, and the worse the pressure resistance is. It is easier to burst and connect when the slurry is squeezed by the slurry before coagulation.

3. The larger the bubble, the worse the pouring stability

4. The larger the bubble, the worse the insulation of foam concrete. The experimental results show that the insulation effect of small foam is better than big foam.

According to the above principle, foam used in foamed concrete must be fine to ensure the quality of concrete. Therefore, the bubble diameter of the foam produced by the foaming mechanism must be less than 1mm, and between 0.5-1cm is the best. If it is too small, it can not only affect the yield but also improve the strength. The test shows that the hole above 1mm in the concrete is the harmful hole, so the bubble LMM below must be controlled. Except for special technical requirements, of course. And the foam must be uniform. The more uneven the foam size, the easier the pouring collapse. In addition, the larger the foam loss, the more waste foaming agent. Because, the size of uneven foam is most likely to burst. The more uniform the foam, the more stable the foam.