Steady state U-value tester for insulating glass

1、 ZKU800 typeSteady state U-value tester for insulating glassOverview:

The ZKU800 steady-state U-value tester for insulated glass is developed based on the method of GB/T22476 "Calculation and Determination of Steady State U-value (Heat Transfer Coefficient) of Insulated Glass" - Measurement of Steady State U-value of Insulated Glass by Protective Hot Plate Method. It is applied to various production enterprises of insulated glass materials, relevant quality inspection departments, units, universities, research institutes and other scientific research units and institutions.

2、 Testing items:

Used to measure the steady-state U value of insulated glass.

3、 Principle:

Under steady-state conditions, a one-dimensional constant heat flux similar to that existing in an infinite flat plate bounded by two parallel uniformly heated plates is established in a uniform plate-shaped specimen with parallel surfaces in the central measurement area of the protective hot plate device.

4、 According to the standard:

GB/T10294 "Determination of steady-state thermal resistance and related characteristics of insulation materials"

GB/T22476 "Calculation and determination of steady-state U-value (heat transfer system) for insulating glass"

5、 ZKU800 typeSteady state U-value tester for insulating glassTechnical parameters:

1. Test piece size: 800mm × 800mm × H (10-120) mm;

2. Measurement range of heat transfer coefficient: (0.25-4.5) W/(m2 • K);

3. Measurement accuracy of heat transfer coefficient: ± 3%;

4. Repeatability of heat transfer coefficient measurement: ± 1%;

5. Cold plate temperature measurement range: (-5-50) ℃;

6. Hot plate temperature measurement range: (10-80) ℃;

7. Temperature measurement value of heat transfer coefficient measuring instrument: cold plate set temperature: 2.5 ℃; Hot plate equipment

Fixed temperature: 17.5 ℃;

8. Temperature resolution: 0.01 ℃;

9. Laboratory temperature: (23 ± 2) ℃;

10. Laboratory humidity: (40-60)% RH;

11. Power supply voltage: 220V, 5kw;

12. Number of specimens: 2 identical specimens;

13. Laboratory environment requirements:

Power supply voltage: 220V, three-phase five wire system;

Laboratory temperature: (23 ± 2) ℃;

Laboratory humidity: (40-60)% RH; ：

The main unit of the experimental equipment occupies a space of 1580mm × 1200mm × 2300mm.

6、 Test device structure:

Adopting the double specimen protection hot plate method (GB10294, GB/T22476), it consists of a microcomputer automatic control system, a metering heating unit, a cold plate unit, a protection unit, an external protection unit, a measurement system, a compression system, a refrigeration mechanism, etc.

1. Microcomputer automatic control system:

The computer output signal is controlled by I/O and D/A conversion to control the corresponding execution components, achieving functions such as temperature control, calculation, temperature acquisition, printing test reports, and displaying process curves. The human-machine dialogue window displays the temperature values of each surface and has a self diagnostic function.

2. Measurement heating unit:

Using a board with excellent thermal conductivity as the heating panel, due to its high thermal conductivity, the temperature of the heating panel surface is more uniform and the thermal inertia is small, which makes the measurement results more accurate.

3. Cold plate unit:

Using a constant temperature water tank to control the temperature of two cold plates, the temperature of the cold plates can be set and automatically controlled by a microcomputer, which is beneficial for controlling the temperature difference on both sides to become the same.

4. Protective unit:

Using the same panel material as the metering heating unit, the temperature difference on both sides is precisely controlled to reduce testing errors.

5. External protective unit:

Using a protective cover made of cork as the outer protective unit makes the experimental environment conditions more stable and beneficial for improving testing accuracy.

6. Measurement system:

Using the more stable Dallas 18B20 digital temperature sensor and high-precision DC power sensor, the data acquisition results are more accurate.

7. Compression system:

Using pneumatic technology, the test piece is automatically compressed by a cylinder without the need for manual adjustment of compression force, making the clamping of the test piece very convenient.

8. Refrigeration mechanism:

It can quickly reduce the temperature of the cold plate and detect the average temperature of the specimen below room temperature, making the detection range larger and not affected by environmental temperature.