How to prevent glass mildew?(second)

Mildew identification and inspection methods:

Visualizing is the most simple and feasible method:

In the concentrated light, the glass placed in the reflected light and transmitted light to observe the glass surface has no spots and fog. If there is a cloth or water can not get rid of spots and fog, indicating that the glass has been moldy. If concentrated light, the eyes can see a few spots and mist is slightly mildew, a lot of spots and mild fog is mild mold. If spots and fogs were observed to be severely moldy by naked eye without exposure to a concentrated beam of light.

In natural light, by spray wet method can also check out severe mold.

How to prevent glass mildew?

Mildew and glass surface characteristics of their own, but also with the float glass packaging measures taken before the mold, packaging, sealing, storage and transportation conditions are closely related. When the float glass molding, annealing, are generally taken online packaging, this time the temperature of the glass is about 50 ~ 100 ℃. Packed glass must be inventory, transport to the user after the time is sometimes very long. If you encounter high temperature, high humidity season, storage and improper, into a box of glass will appear moldy.

Mildew appear on the air surface of the float glass because of the mechanism of the glass surface of the tin glass itself defects, the original film packaging and transport storage process, mold the process at room temperature or slightly higher than room temperature conditions.

The glass surface has the following characteristics:

① during the annealing process, alkaline ions move to the glass surface;

② surface and O2, SO2, H2O and HCL reaction;

③ surface strength is low, prone to Griffith cracks;

④ easy on the glass surface Ion exchange;

⑤ on the surface of the glassy Sio2 can be hydrolyzed, the Si-O bond breakage;

⑥ surface components easy to evaporate and decomposition;

⑦ surface easy crystallization;

⑧ surface with Run temperature and so on.

The defects on glass surface:

① the existence of a glass surface porous or void:

Mainly due to the formation of the volatile surface composition, due to the volatilization of alkali formation in the surface positioning, scanning electron microscopy, float glass surface than the lower surface (tin surface) have more bulge and depression.

② the existence of cracks in the glass surface:

These cracks are not mechanical damage, but rather with the internal structure: the surface strength is low, prone to crack.

③ mildew storage and transportation process:

Silicate glass mildew phenomenon occurs mainly in the packaging of the storage or transport process, which is packaging, storage and transportation.

Packaging can be in the hot state, cold state of packing with paper or anti-mildew powder,

① usually stored in a well ventilated warehouse;

② do not allow the glass box directly on the warehouse in the wet ground;

③ Do not store the glass outdoors and in direct sunlight.