GB/T 39548-2020Determination of retention rate on thermal resistance of vacuum insulation panels(VIP) in hygrothermal conditions (English PDF)

1 Scope

This standard specifies the method for measuring the retention of thermal resistance of vacuum insulation panels under specified temperature and humidity conditions:

This standard applies to the evaluation of long-term durability of vacuum insulation panels, and other materials can also be referred to:

2 Normative references

The following documents are indispensable for the application of this document: For dated reference documents, only the dated version applies to this article

Pieces: For undated references, the latest version (including all amendments) applies to this document:

GB/T 4132 Thermal insulation materials and related terms

GB/T 10294 Determination of steady-state thermal resistance and related characteristics of thermal insulation materials: Protective hot plate method

GB/T 10295 Determination of steady-state thermal resistance and related characteristics of thermal insulation materials by calorimeter method

GB/T 37608 vacuum insulation board

3 Terms and definitions

The following terms and definitions defined in GB/T 4132 and GB/T 37608 apply to this document:

3:1

Thermal resistance retention rate retentionrateonthermalresistance

Under the specified temperature and humidity conditions, the sample is processed for a certain period of time, and the ratio of the thermal resistance of the central area after processing to that before processing:

4 Equipment

4:1 Temperature and humidity control box: temperature fluctuation is not more than ±2°C; relative humidity fluctuation is not more than ±3%:

4:2 Thermal conductivity tester: meet the requirements of GB/T 10294 or GB/T 10295:

4:3 Environmental chamber: The temperature fluctuation is not more than ±2°C:

5 Sample

5:1 Sample requirements

The sample should be a complete vacuum insulation panel: The sample size is the original size of the sample:

5:2 State adjustment

The sample should be placed for no less than 72h under the conditions of temperature (23±2)°C and relative humidity (50±5)%:

6 Test procedure

6:1 Thermal resistance test in the central area before treatment

Use a thermal conductivity tester to test the thermal resistance of the central area of the sample before processing, take three significant figures, and record the thickness of the sample: If the sample […]