ОСНОВНЫЕ ПОЛОЖЕНИЯ

INSULATING GLASSUNITSFORBUILDING

Method of Determination of Resistance to Atmospheric Effects and Estimation of Life Circle

1 Field of Application

This standard applies to glazing units for construction (hereinafter, glazing) and sets forth a method of the determination of their resistance to atmospheric effects and estimation of life circle by changes in the physical and mechanical parameters under the effect of cyclic loads. The method set forth herein can only be used for the determination of glazing resistance to weakly corrosive chemical media and their compatibility with materials used in glazing manufacture.

The method can be used for qualification, typical, certification, periodical and other types of tests.

4 Principle of the Method

4.1 The principle of the method is the measurement of the typical parameters of glazing exposed to cyclically alternating positive and negative temperatures, moisture, ultraviolet radiation and weakly corrosive chemical media (solutions), the total effect of which imitates critical loads that may occur during the use of glazing.

4.2 The parameters characterizing the resistance of glazing to atmospheric effects and estimation of their life circle are: dew point temperature (hereinafter, dew point), desiccant efficiency and glazing tightness.

5 Equipment

Installation (set of equipment) that provides for the establishment, adjustment and maintaining of the required test conditions:

- ultraviolet radiation in the 280-400 nm wavelength range with intensities of 60±2 and 80±2 W/m2 at 50±2°C temperature in the "black panel" thermometer chamber as measured during equipment setup;

- watering of the test samples;

- exposure to positive temperatures up to 90°C with measurement accuracy of within 2°C at relative air humidity of 95±5%;

- exposure to negative temperatures down to -70°C with measurement accuracy of within 2°C;

- exposure to liquid (or gaseous) weakly corrosive medium at 20±3°C.

The equipment (including cassettes or other sample claming devices) shall not affect the test results. The distance between the samples with one another and samples with chamber walls shall be at least the double sample thickness.

The following equipment is used for the measurements:

- photographic intensity meter that provides for 280-400 nm UV intensity measurement with measurement accuracy of within 15%;

- liquid thermometers with the -100 to +100 measurement ranges and measurement accuracy of within 0.5°C;

- general purpose laboratory balance with measurement accuracy of within 0.1 g;

- slide gage according to GOST 166;

- ruler according to GOST 427;

- dew point monitoring device equipped according to GOST 24866;

- glass, porcelain, plastic or enameled steel container for filling with water (chemical solutions) and placement of the glazing sample in accordance with the requirements of GOST 24866;

- clock with a measurement accuracy of within 10 sec/day.

The test specification documents are developed depending on the plant (set of equipment) used to provide a measurement accuracy within the limits as specified herein.

The test equipment and devices shall conform to the requirements of noramtive documentation (hereinafter, ND) and pass testing in duly approved procedures.

6 Test Preparation Procedure

6.1 The test mode is set before the tests.

Tests are made in one of the modes as specified in Table 1.

Table 1. Cyclic Test Modes, h

Mode Number / Dipping into a Saline Solution / Ultraviolet Irradiation / Dipping into an Alkaline Solution / Freezing / Dipping into Acid Solution / Heating / Cycle Duration
I / 0.3 / 1.0 / 0.3 / 3.0 / 0.3 / 17.0 / 22.0
II / 0.3 / 0.5 / 0.3 / 3.5 / 0.3 / 17.0 / 22.0
IIIM / 0.3 / 0.5 / 0.3 / 4.5 / 0.3 / 16.0 / 22.0
IV / According to Appendix A
Notes
1. Freezing temperature:
mode I: -30°C;
mode II: -30°C and -50°C each sixth test cycle;
mode IIIM: -40°C and -60°C each sixth test cycle.
2. Heating temperature for all modes: 70-2 °C at relative air humidity of 90-100%
3. The saline solution is 3% water NaCl solution.
The alkaline solution is 3% water NaHCO3 solution.
The acid solution is 3% water H2SO4 solution.
The test solution temperature is 20±3 °C.
4. Exposure to moisture by dipping into the container can be replaced by watering of the glazing with an appropriate solution.
5. The ultraviolet radiation intensity is 60±2 W/m2 at 50±2 °C. For glazing that is mainly used for fenestration structures, the ultraviolet radiation intensity is 80±2 W/m2 at 50±2 °C.
For glazing that is intended for fenestration structures without sealant protection from UV, additional 22 h long UV testing at 80±2 W/m2 is made after each 12 cycles.
6. The time intervals between each loading within a test cycle shall not exceed 20 minutes at 21±4 °C.
7. The time of temperature growth and decline incases of sample heating and freezing, respectively, shall be included into the time intervals as specified in the table and total to not more than 40 min. The temperature rate shall not exceed 3°C/min.

Mode I testing is used for multiple glass units intended for installation in climatic regions where the average January monthly temperature is not lower than -10°C (the test temperature is -30°C).

Mode II testing is used for multiple glass units intended for installation in climatic regions where the average January monthly temperature is from -10°C to -20°C (the test temperatures are -30°C and -50°C).

Mode IIIM testing is used for frostproof multiple glass units intended for installation in climatic regions where the average January monthly temperature is below -20°C (the test temperatures are -30°C and -60°C).

Mode IV testing (Appendix A) is mainly used for assessing the quality of multiple glass units intended for export.

In some cases upon necessity (e.g. under specific service conditions of multiple glass units) and upon agreement with the customer it is allowed to modify the testing procedure as per this standard. The modifications shall be reflected in the specially developed test schedule and the executive (laboratory) documentation (including log books and test reports).

6.2. Sampling

The samples are taken from a lot of multiple glass units that has passed acceptance testing at the manufacturer's premises in accordance with the GOST 24866 or other glazing manufacture ND. The tests shall be made not earlier than two weeks following glazing manufacture.

For testing, at least six samples of each type of multiple glass units shall be taken, sized at least (350x350)±2 mm. Sampling shall be documented in a report duly executed in accordance with the approved sampling procedure.

The glazing samples shall be held unpacked in the laboratory at 22±3°C and relative air humidity of 55±5% for at least three days. During this period the samples shall be duly protected from direct sunlight.

Before the tests all the samples shall be checked for ND requirements to appearance, marking, sealant application correctness, nominal dimension tolerance and lack of cracks and mechanical damage. If at least one sample does not conform to the ND requirements, all the samples shall be replaced. The results of this checking shall be shown in the executive (laboratory) documentation.

6.3. Test Equipment Preparation Procedure

The operation mode of the test equipment is set in accordance with the planned test mode and the equipment operation instructions.

The ultraviolet radiation intensity is monitored with the photographic intensity meter before the onset of the test and then every 20 h.

7 Testing Procedure

7.1 The testing procedure is as follows:

- preliminary sample testing;

- testing in cyclic modes as per Table 1 (modes I, II, IIIM and IV);

- final testing.

7.2 Preliminary testing is made to determine the following parameters:

- air-tightness in the water filled container (six samples);

- dew point (six samples);

- desiccant efficiency (three samples; destructive testing).

The test methods are according to GOST 24866 (air-tightness testing according to Appendix B; sample exposure time 24±1 h).

In case each sample gives satisfactory test results for each of the parameters, three samples after nondestructive testing (for air-tightness and dew point) are forwarded for cyclic mode testing. If at least one of the samples shows deviation from the ND requirements, all the samples shall be discontinued from the tests and replaced. Preliminary testing results for each sample and for each parameter shall be shown in the executive (laboratory) documentation.

7.3 After the end of each test cycle (for mode IV, after each 8 cycles), the samples are visually checked for the presence of cracks, water penetration marks and appearance defects. If at least one of the samples shows deviation from the ND requirements, all the samples shall be discontinued from the tests, and the results are considered unsatisfactory.

7.4 After each 12 test cycles (for mode IV, after the first part of tests), the samples are visually checked for quality and tested for dew point. If at least one of the samples shows deviation from the RD requirements, the tests shall be stopped.

7.5 After the end of the test schedule, the samples are visually checked for quality and tested for dew point and desiccant efficiency. The dew point and desiccant efficiency tests are made not earlier than in 8 hours after the end of climatic cycling.

8 Estimation of Results

8.1 Multiple glass units are considered having passed atmospheric effect resistance testing, if all the samples after the full test schedule have dew point and desiccant efficiency parameters in accordance with the ND requirements.

8.2 The life circle of the multiple glass units is assessed by the number of climatic testing cycles, each cycle being considered equal to 7 conventional use years. If tests were stopped during a 12-cycle range, the life circle of the samples is determined by interpolation.

For example, if one of the test samples lost air-tightness at the 19th cycle of climatic testing, the tests are interrupted, and the other multiple glass unit samples are checked for normal dew point, desiccant efficiency and appearance. If the result of these checks is satisfactory, the life circle of the multiple glass units is calculated as (18/12)x7 = 10.5 conventional use years.

8.3 The satisfactory result of teh full test cycle for multiple glass units is considered evidence of their conformity to the requirements regarding frost resistance, weakly corrosive media resistance and compatibility with materials used for manufacture.

8.4 The life circle of multiple glass units tested in mode IV is not subject to quantitive estimate.

9 Result Presentation

The test results shall be presented in the form of a test report showing the following data:

- name, legal address and accreditation certificate number of the testing center (laboratory) that performed testing;

- name and legal address of the testing customer;

- name and legal address of the test product manufacturer;

- name of the test product and the regulatory document that describes its quality requirements;

- descriptions of tested product samples (size, design, desiccant and sealant types etc.);

- date the samples were received by the testing center (laboratory);

- sample registration number at the testing center (laboratory);

- test results in tabulated form and multiple glass units life circle estimates;

- sample testing date;

- signatures of the testing center (laboratory) director and the testing person;

- stamp of the testing center (laboratory).

Mode IV Testing Procedure

The testing procedure consists of two parts:

- the first part includes 56 thermal testing cycles at temperatures from -18±2 to +53±1 °C at recommended relative air humidity  95% with temperature rate of 14±2 °C/h during 12 hours;

56 thermal testing cycles 12 hours each (4 weeks)

1174±4 hours of constant temperature (7 weeks)

Relative air humidity  95%

Figure A.1 Mode IV Multiple Glass Units Testing Chart

Relative air humidity

Air temperature

Figure A.2 Chart of on Testing Cycle (First Part of Mode IV) Testing

- the first part includes exposing the samples to a constant temperature of 58±1 °C and relative air humidity  95% during 7 weeks.

If two parts of the test are made in different chambers, a 2-4 h interval is allowed for transferring the samples between the chambers.

1