JC/T 1079-2008Vacuum glazing (English PDF)

7.9 Thermal insulation performance

The sample is a 1000mmx1000mm flat vacuum glazing which is made of the same

materials and same thickness with the products and under the same process conditions.

The measurement shall meet the requirements of GB/T8484.The measurement can be

conducted in accordance with the requirements of Annex A as well.

When conducting type test or arbitration test, GB/T 8484 shall be complied with for the

measurement.

7.10 Radiation resistance

7.10.1 Specimens are two 510mm x 360mm flat vacuum glazing samples made of the

same materials, thickness and technical conditions of products.

7.10.2 The requirements for the instrument and equipment for test, the conditions and the

steps shall be consistent with the requirements of Article 6.5 of GB/T 11944-2002, but the

UV irradiation time shall be 200 h. The K value of each sample shall be measured before

and after irradiation. The rate of change of K is the percentage OF the absolute value of the

difference of K before and after the irradiation AND the K before the irradiation.

7.11 Durability of climate cycle

7.11.1 Specimens are two 510mm x 360mm flat vacuum glazing samples made with the

same materials, thickness and technical conditions of products.

7.11.2 Testing according to the requirements of Article 5.6 of GB/T 11944-2002, the value

K of each sample shall be measured before and after the test. The change rate of K value is

the percentage OF absolute value of difference K before and after the experiment AND the

K value before the experiment.

7.12 Durability of high temperature and humidity

7.12.1 The samples are two 510mmx360mm flat vacuum glazing which are made of the

same materials and same thickness with the products and under the same process

conditions.

7.12.2 Testing according to the requirements of Article 6.6 of GB/T 11944-2002, the value

K of each sample shall be measured before and after the test. The change rate of K value is

the percentage OF absolute value of difference K before and after the experiment AND the

K value before the experiment.

7.13 Sound-insulated performance

Measuring head and isolating ring are all made of high thermal conductivity materials copper

and aluminum. The measuring error of instrument shall be less than ± 5%.

A.5 Test procedures

A.5.1 Thermal conductivity measurement of vacuum glazing, Cmeasure

A.5.1.1 Firstly put thermal conductivity measuring board of vacuum glazing at top of

standard board. And then put vacuum glazing sample between cold plate and the measuring

head. The distance of measuring head from the specimen edge shall be greater than 50

mm.

A.5.1.2 Set the temperature of cold plate as 10°C. Set the temperature of hot plate as 40°C.

Heat the measuring head to make it reach to specified value. The temperature of cold plate,

hot plate and measuring head shall be stabilized within ±0.01°C.

A.5.1.3 After the instrument is stable, record instrument thermal conductivity value, that is,

Cmeasure and temperature Tmeasure of measuring head.

A.5.2 Radiant heat conductivity measurement of vacuum glazing, Cradiation

A.5.2.1 Replace the vacuum glazing thermal conductivity measuring plate with vacuum

glazing radiant thermal conductivity measuring plate. And repeat the steps of A.5.1.1 and

A.5.1.2.

A.5.2.2 After the instrument is stable, record instrument thermal conductivity value, that is,

Cradiation.

A.5.3 Data processing

A.5.3.1 Correction of the actual measured values

Actual measuring value of vacuum glazing thermal conductivity shall be revised according to

formula (A.2). And it will get revised vacuum glazing thermal conductivity value C'measure.

C'measure = (Cmeasure – Cradiation) + Cradiation (272/[(Tmeasure + Tcold)/2 + 273])3... (A.2)

Where.

Cmeasure - Measured value of thermal conductivity of vacuum glazing, in the units of

W/(m2-K);

Cradiation - The unit of radiant thermal conductivity measuring value of vacuum glazing, in

the unit of W/ (m2-K);

C'measure - The unit of revised thermal conductivity measuring value of vacuum glazing,

in the units of W/ (m2-K);

Annex B

(Informative)

Structural diagram of vacuum glazing