14 min read

With the increasing emphasis on energy conservation and environmental protection by governments and societies around the world, the application of insulating glass for doors, windows, and curtain walls is no longer restricted by regions. Because glass occupies an important position in the energy saving of building doors, windows, and curtain walls, the heat insulation and energy-saving issues related to insulating glass have also attracted the attention of producers and users. For the doors, windows, and curtain walls of high-rise buildings, the way for insulating glass to prevent condensation is to use a rigid warm edge system that not only has the function of heat preservation and heat insulation but also has a certain mechanical strength.  

Keywords: U value, glue injection, curtain wall, insulating glass, Warm Light system, compressive performance, sealing performance, Canada, the United States, experiment

How to improve the service life of insulating glass?

The edge area of the insulating glass is the lowest temperature area in the entire glass system. This is mainly because the edge area (periphery) of the insulating glass is the place where condensation begins to form. In some places where we live, the winter temperature in the northern hemisphere can drop to minus 30°C or more. In these places, people usually choose a triple-glazed door and window system or a double-glazed door and window system. Such systems are generally cumbersome. In some high-rise buildings in the northern hemisphere, we usually use some other thermal insulation methods to ensure the non-condensing properties of the glass system.

But with the long-term application of insulating glass, we have found that many factors affect the working life of the insulating glass. These materials must be tested for water vapor transmission, argon retention, grid strip sticking, UV resistance, and exhaust performance of functional materials in closed cells.

In areas with large temperature differences between winter and summer and serious energy waste, the percentage of energy lost through the glass to the total loss is increasing year by year. Our commonly used insulating glass has been greatly improved in terms of sound insulation and heat insulation compared with ordinary single-layer glass. However, because ordinary aluminum spacers are still used between each layer of glass, some heat can pass through and the thermal conductivity is very high. The high transmission of aluminum spacers has also made it difficult to reduce the thermal conductivity of insulating glass. When the designers of glue-injection thermal insulation technology saw this problem, a very creative idea emerged spontaneously. It is possible to overcome this difficulty if the aluminum spacer of the insulating glass is also designed as a heat-breaking cold bridge system by using the glue-injection heat-breaking technology. After a long time of design and practice, a historically significant technology was born and obtained a US patent at the same time. This is an important branch of glue injection thermal insulation technology—WARM-LIGHT thermal insulation aluminum strip technology. This is a new technology that is completely different from the soft warm edge system currently appearing on the market.

Figure 1 Azon Warm-Light thermal insulation aluminum strip 1

Figure 1 Azon Warm-Light thermal insulation aluminum strip 1

The main points of WARM-LIGHT thermal insulation technology from the following aspects:

1. Warm-Light thermal insulation system can effectively prevent condensation on doors and windows

We can use the principle of glue injection and thermal insulation and different design methods to complete the manufacture of Warm-Light thermal insulation aluminum partition.

To illustrate the performance characteristics of this kind of spacers, we used a computer simulation program to set up experimental models of Warm-light aluminum spacers, ordinary aluminum spacers, and stainless steel spacers. We found that the temperature of ordinary aluminum spacers at the junction of aluminum door and window profiles and glass is -0.1℃, stainless steel spacers are 0.4℃, and Warm-light is 5.3℃. Similarly, we do the same experiment in the wooden window system. For the temperature at the junction of the window material and the glass, the aluminum spacer is -0.1℃, and the stainless steel spacer is 0.4℃. At the same point, the temperature of Warm-light It is 5.3°C. We can also experiment with these three types of insulating glass spacers: within a space distance of less than 25.4mm, the temperature of the edge area of the insulating glass can change from 11°C to 0°C. The following figure represents the use of these three types. The temperature change is experienced by the surface of the glass during the interval. 

Note: 25.4mm is the distance calculated from the contact point of the door and window profile and the glass, extending to the top of the glass.

Figure 2 The insulating glass aluminum spacer strip 1

Anti-condensation coefficient (CFR) is a parameter that measures the anti-condensation ability of door and window systems. From the following experimental results, we can see that the Warm-light heat-insulating aluminum spacer is 120% more than stainless steel. The U value is reduced to 0.19W/m^2*C

Figure 2 The anti-condensation coefficient spacer strip 1

Figure 3 U profile system spacer strip 1

Figure 3 U profile system spacer strip 1

2. How does the Warm-light thermal insulation system make the U value of aluminum windows reach 0.44  

According to the regulations of the state of Massachusetts, the U value of residential houses must be lower than 0.44 when replacing doors and windows. This may be more difficult for some window types. So, can we help manufacturers of building doors and windows meet the 0.44U value requirement? Although this goal is somewhat difficult to achieve, it is possible to achieve it if the Warm-Light system is used.

At present, the thermal insulation performance of European and American door and window systems are mainly based on a ratio, namely the U value. The U value is a measure of the heat transfer performance of doors and windows. The lower the U value, the less heat is lost. Of course, there are several other key values for door and window products: such as shading coefficient-used to measure the shielding performance of doors and windows to sunlight; air leakage-used to measure the airtightness of door and window products. So, how does Yasong Technology make aluminum windows reach a U value of 0.44? To achieve this, we must comprehensively use other door and window insulation methods. Its configuration conditions are the use of glue-injected heat-insulating aluminum door and window profiles, inert gas-filled hollow glass (the glass is Low-E glass and the configuration of Warm-light hollow heat-insulating aluminum partitions), good sealing treatment, and correct Hardware installation. If we can achieve this, the U value of aluminum windows can be reduced to 0.44 or even lower.

3. Warm-light thermal insulation system has good mechanical properties

Many thermal insulation aluminum partitions are positioned for commercial or civilian use. Warm-Light⑩ is well applied in the civilian market. What is surprising is that its performance diversity allows it to perform well in the commercial field. Warm-Light⑩ is the only technology that can improve the overall structural performance of doors and windows. Yasong has tested Warm-Light⑩ and ordinary aluminum partitions used in general commercial buildings. The structural requirements and wind pressure of commercial buildings and the structural stability of the entire doors and windows must be considered. They must withstand inspection while maintaining the structural integrity of the building. Inheriting the excellent mechanical properties of AZON polyurethane thermal insulation adhesive and the traditional aluminum channel design, the AZON WARM-LIGHT hard edge warming system has good mechanical properties and is the only one that can be applied to high-rise building door and window curtain wall systems. Insulating glass warm edge system.

(A) Deformation analysis of insulating glass aluminum spacer arm bending experiment                             

Figure 4 the AZON WARM-LIGHT insulating glass hard edge warming system 1

Figure 4 the AZON WARM-LIGHT insulating glass hard edge warming system 1

Figure 5 The deformation analysis of insulating glass spacer 1

Figure 5 The deformation analysis of insulating glass spacer 1

(B) Analysis of the compressive performance of insulating glass aluminum spacers

Figure 6 The analysis of compressive performance of insulating glass spacer 1

Figure 6 The analysis of compressive performance of insulating glass spacer 1

Because this hollow aluminum partition has good heat insulation, compression resistance, and sealing performance, in mainland China, several glass manufacturing companies have used Warm-light in curtain wall projects in the northeast region, and it has demonstrated good performance. The result. In addition, the airport project can make full use of its high sound-absorbing performance, and the museum is using three-layered glass with two layers of Warm-light to prevent mold on old documents or artworks. At the same time, we can see that in hurricane-prone areas, Warm-light is becoming a heat-insulating aluminum partition for insulating glass that can effectively resist wind and water pressure.

Performance experiment of Warm-Light

Since the advent of insulating glass, considerable progress has been made in improving the performance of the final doors and windows. The low-emissivity film, inert gas, and insulating glass spacers are several important areas that are relatively concentrated. Among them, the hollow glass aluminum spacer is mainly used to improve the edge temperature of the glass.

Ordinary aluminum spacers are only more durable. With the use of insulating glass for a long time, many factors can affect the life of the insulating glass, especially water vapor transmission, argon retention, grid strip sticking, UV resistance, and functional materials in closed cells. Of exhaust. After the latest industry testing, it is proved that the Warm-light insulation aluminum partitions of Asong are still performing well even in damp and other outdoor conditions. In North America, many glass and door and window manufacturers send their products to laboratories and testing centers in the United States and Canada for testing. The following are some of the main experimental methods and some experimental results.

ASTM E773 E774

The American Society for Testing and Materials (ASTM) has established a unified standard size, the number of units, testing time, and performance requirements for insulating glass. ASTM E773 is a standard for testing the durability of sealing strips. ASTM E774 divides insulating glass into three types based on the durability-tested under various climatic conditions. When the numbers of the various cycles come out, remove the frosting point to obtain the specimen. Specimens will be divided into three categories, Class C, Class CB, and Class CBA, with the last one being the highest grade. Every insulating glass manufacturer will do product testing. Warm-light has been tested in various installation modes and successfully obtained the CBA level.


ASTM E773 standard test
The initial dew point of the unit under testC LevelCB LevelCBA Level

Smoke test*RH**WC*RH**WC*RH**WC
FFFFFFF
1<-90-79<-90-83-81-85-70
2<-90-80-75-80-76-84-86
3<-90-76-75-71-80-78-83
4<-90-83-83-86-76-81-84
5<-90-79-84-85-84-83-83
6<-90-68-87-70-81-80-78
7<-90Pass the smoke test
8<-90Pass the smoke test
9<-90
10<-90
Requirements: no smoke<-30<-30<-30<-30<-30<-30
Note: IGCC prototype machine P-1249 passed ASTM E773 test method CBA level
GH: After the tested unit is exposed to 95% humidity
WC: The tested unit accepts continuous weather requirements test

Frost point test

This test is to detect when the temperature of the outer surface of the glass reaches the frost or condensation on the inner surface. When hollow glass is at minus 23 degrees, if frost or condensation has not formed after 3 minutes, it will pass the test. The Canadian Insulating Glass Association (IGMAC) and the Sealed Insulating Glass Association (SIGMA) have respectively established standard testing temperatures.

Canadian smoke detection

Insulating glass manufacturers must ensure that the work area is clean when assembling the insulating glass, and use collar parts that will not cause air leakage and smoke in the hollow part. The most stringent procedure for smoke detection is CAN/CGSB12.8. Two 355.6 mm × 504 mm hollow glass windows are installed in an experiment box, which is equipped with an ultraviolet lamp and a small circulating fan to keep the temperature at 60 degrees.

They were placed in this environment for seven days and then placed in a special observation box. Observe whether there is smoke or other residues on the inner surface.

Dallas smoke test

AZON's quality control procedures require continuous random testing. A screening test with interrelated results has been designed to increase the frequency of the test and reduce the difficulty of the test. Originally, this test was used to estimate the UV resistance of printed panes. The sediment at the bottom of the retest cup can be used to estimate the quality of the spacer.

Water vapor transmission rate  

In the production of insulating glass, the test sealant is to maintain good airtightness. It is important to have a sealed unit that can prevent the permeation of water vapor. The water vapor transmission rate (MVT) test is to detect the water vapor transmission rate of the sealant. Water vapor must not enter the hollow part.

Table II

Water vapor transmission rate test result
LaboratoryDetroit Test LabCourtaulds Aerospace
Test methodsASTM E-96ASTM E-398
Test temperature (℃)2338
Test humidity50%100%
Test period(Days)231
Gain (g)0.0983.46
Area (square feet)0.19610.78
Thickness of the tested part (inch)0.1550.0695
Partial water pressure (mmHg)10.550
Water vapor transmission rate(G*inch/square foot*day)0.0340.0223

Argon storage capacity  

Keeping argon leakage is as important as preventing water vapor from entering the hollow part of the insulating glass. The Canadian Insulating Glass Association (IGMAC) and the Sealed Insulating Glass Association (SIGMA) are looking for the most effective way to test the argon storage capacity. Because argon is heavier than air, evacuating the air between two layers of glass and then filling this inert gas has proven to be an effective way to improve the performance of insulating glass. But argon is invisible, so when an insulating glass unit is filled with argon, there is a question that will be raised, that is, "How long is the shelf life of argon?" The Canadian Insulating Glass Association (IGMAC) is taking measures To measure the gas in the hollow glass.

The test results of Warm-Light are shown in Table 3.

Table 3 A Test results under high humidity
Gas composition %

NitrogenOxygenArgon Gas
Test unit numberForwardRearForwardRearForwardRearRemark
1311129586
2478121940Loose stopper
336119592
426119692
526129691
624119694
7410229387
827129690
Table 3 B The results of various weather cycle tests
Gas composition %

NitrogenOxygenArgon Gas
Test unit numberForwardRearForwardRearForwardRearRemark
925119694
102-1-96Test is rupture
1137129691
1227129691
1325119694
142571159627Loose stopper
15229189662Loose stopper
1636229591

Result: The gas concentration before and after the test is shown in Table 3

Affinity of sealant 

ASTM C794-80 is an adhesion test, SIGMA73-8-26 is a sealant affinity test. They are used to test the affinity of the sealant and spacers used in the production of insulating glass.

The Warm-Light spacer has been tested for affinity with several sealant systems. The test results show that it has a good affinity and adheres well to any of the tested sealants.

Infrared thermography test

The temperature test results are obtained by using ultraviolet light to display and record thermal performance. The hollow glass is mounted on a 152.4 mm fixed frame and placed in an environmentally friendly room. The outside temperature is kept at minus 20°C and the wind speed is 12 km/h. The temperature inside is kept at 20°C.

An infrared camera is used to record the temperature changes on the inner surface of the glass from the edge of the heat insulation strip to the center of the glass. A thermocouple mounted on the glass is used to change the reading of the camera.

The results show that, compared with the insulating glass equipped with ordinary aluminum spacers, the insulating glass equipped with Warm-Light can improve the thermal performance by 2.8°C to 5.0°C.

Processing technology and characteristics of use:

For producers, Warm-Light⑩:

◇Easy to install decorative strip

◇No need to invest in any new equipment

◇No need to change production and processing methods

◇Applicable to various adhesives

◇It can be mechanically connected or bent into any shape required

◇No deformation under extreme temperature conditions or exposed to the sun

For door and window buyers, Warm-Light⑩:

◇Can effectively reduce condensation

◇It can increase the edge temperature of the glass surface

◇The K value of the entire door and window system can be reduced

◇It is the most characteristic spacer on the market

◇No deformation


Insulating glass can be produced and processed by Jinan LIJIANG Glass plate-pressed air-filled insulating glass production line, and Warm-Light hard warm-edge spacers can be bent by Jinan LIJIANG Glass Spacer Bar Bending Machine.


For more information about Jinan LIJIANG Glass insulating glass processing equipment and insulating glass processing accessories, please click here to learn more. 

Comments
* The email will not be published on the website.