What about casting coating without film

If the die is not hung, it means poor coating and hanging. The reasons for poor coating and hanging should be found out from many aspects:

① The additives of the coating have poor coating property, which is easy to be accepted;

② The same additives, such as coarse aggregate mesh, must have poor coating property;

③ The same additive and the same aggregate, too dilute concentration will inevitably lead to poor coating;

④ With the same aggregate number and different aggregate proportion, it is inevitable that the coating property of aggregate ratio is poor;

⑤ The coating should be used in agitated state or flow dynamic state, and the long-term static state is necessarily worse than the flow or agitation state;

⑥ The coating with long-standing fermentation deterioration or dehydration stratification must have poor coating hanging property.

Therefore, when the coating hanging performance is not ideal, first investigate the reasons and then make countermeasures, don’t muddle down the conclusion, and then muddle up the adjustment to go, it may be worse.

In terms of aggregate proportion, many people neglect or have one-sided understanding, such as Baozhu sand, whose proportion is 4-4.2g/cm3, while the proportion of quartz powder is only 2.2-2.4g/cm3. Obviously, if Baozhu sand powder accounts for 100% of the aggregate powder, the result must be quite poor coating, so the proportion of Baozhu sand is generally not more than 35% in the preparation of coating.

There is a misunderstanding not to fall into, that is, the understanding of baumead. Baume degree = 144.3-144.3/d, where D is the density of paint slurry, different aggregate powder or the same aggregate powder with different mesh, its water adaptability is completely different, so it is inevitable to get different Baume degree values, so each factory has its own Baume degree, without uniform parameters, do not follow suit, let alone mislead.

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