How Much Do You Know About LOW-E Glass

A good piece of glass makes every ray of sunshine warmer. LOW-E insulating glass, because of its extraordinary characteristics are used by many high-end buildings, including the White House, Burj Al Arab hotel and other world buildings.

Since 1978, interqane in the United States has successfully applied "LOW-E" glass to buildings. It has been praised repeatedly, and many architects believe that the superiority of "LOW-E" is beyond question.

Since 1990, the use of "LOW-E" in the United States has been increasing at a rate of 5% per year. Nowadays, energy-saving glass doors and Windows have received more and more attention, from high-end buildings to door and window companies, and then to many owners who attach importance to the quality of life, the energy-saving effect of doors and Windows has become an important factor in evaluating its advantages and disadvantages.

What is LOW-E glass?

LOW-E glass is low-Emissivity glass, which is coated on the glass surface, and is formed when the emissivity E of the glass is reduced from 0.84 to below 0.15.

What are the characteristics of LOW-E glass?

① High infrared reflectivity, can directly reflect far infrared thermal radiation.

② The surface emissivity E is low, and the ability to absorb external energy is small, so that the heat energy re-radiated is less.

(3) The shading coefficient Sc has a wide range, and the transmission amount of solar energy can be controlled according to needs to meet the needs of different regions.

Why does LOW-E film reflect heat?

LOW-E film layer is plated with silver layer, silver can reflect more than 98% of the far infrared thermal radiation out, so as to reflect the heat directly like a mirror reflects light. The shading factor Sc of LOW-E can range from 0.2 to 0.7, so that the direct solar radiation energy entering the room can be regulated as needed.

What are the main types of mature coated glass processes?

There are two main types: online coating, vacuum magnetron sputtering coating (also known as off-line coating).

The in-line coated glass is manufactured in the float glass production line, and this kind of glass has a single variety, poor thermal reflection and low manufacturing cost. Its advantage is that it can be processed by hot bending.

The off-line coated glass has various varieties, excellent thermal reflection performance and obvious energy-saving characteristics. Its disadvantage is not hot bending processing.

Can LOW-E glass be used in a single piece?

LOW-E glass manufactured by vacuum magnetron sputtering process can not be used in a single piece, and can only be used by synthetic insulating glass or laminated glass. But its emissivity E is much lower than 0.15 and can be as low as 0.01.

LOW-E glass manufactured by the online coating process can be used in a single piece, but its emissivity E=0.28, strictly speaking, can not be called LOW-E glass (scientifically, objects with emissivity E≤0.15 are called low-radiation objects).

How does LOW-E glass work in summer and winter?

In winter, the indoor temperature is higher than the outdoor, far-infrared thermal radiation mainly comes from the room, LOW-E glass can reflect it back to the room to keep the heat inside. For part of the solar radiation from the outside, LOW-E glass can still allow it to enter the room, and this part of the energy is absorbed by the indoor object and converted into far-infrared thermal radiation and left in the room.

In summer, the outdoor temperature is higher than the indoor, far-infrared thermal radiation is mainly from outside the city, LOW-E glass can reflect it out to prevent heat from entering the room. For outdoor solar radiation, low-E glass with LOW shading coefficient can be selected to limit its entry into the room, thereby reducing certain costs (air conditioning costs).

What is the role of filling argon in LOW-E insulating glass?

Argon is an inert gas, and its heat transfer is worse than air, so it can reduce the U value of insulating glass and increase the heat insulation of insulating glass. For LOW-E insulating glass, argon also has the role of protecting LOW-E film.

How much UV can LOW-E glass attenuate?

LOW-E glass can reduce UV rays by 25% compared to ordinary single transparent glass. LOW-E glass reduces UV rays by 14% compared to heat-reflecting coated glass.

On which surface of the insulating glass is the LOW-E film suitable?

The insulating glass has 4 faces, which are 1#, 2#, 3# and 4# surfaces from the outdoor to the city. In areas where heating demand exceeds cold demand (northern regions), the LOW-E film layer should be on the 3rd # surface. Conversely, in areas where the cooling demand exceeds the heating demand (the southern region), the LOW-E film layer should be located on the 2nd # surface.

How long does the LOW-E film last?

The duration of the coating layer is the same as the duration of the sealing of the insulating glass space layer.

How to determine whether there is LOW-E film plated on insulating glass?

It can be monitored and judged according to the following steps:

A. Observe the four images that appear inside the glass (in other words, there are four flames and four objects).

B, put the match or bright part in front of the window (whether you are in the city or outdoors), if the LOW-E glass, there is an image of the color is different from the other three images, if the color of the four images is the same, it can be determined that there is no LOW-E glass.

Is there anything users need to do to maintain LOW-E glass products?

No need! Because the LOW-E film layer is sealed in the middle of insulating glass or laminated glass, there is no need to maintain, just keep the glass surface clean.