Thermal shock test chamber>, also known as high and low temperature shock chamber>, is used to test the material structure or composite material, which can withstand the continuous environment of extremely high and extremely low temperature at a glance Environmental testers are widely used in environmental testing of materials or products (or semi-finished products) in metal, plastic, rubber, electronics and other industries.
Heat and Cold Shock Test Chamber>CautionMeasures for correct use:
1. When conducting environmental tests, you must be familiar with the required test pattern performance, test conditions, test procedures, and test techniques. It is necessary to be familiar with the technical performance of the test equipment used and the construction of the equipment, especially the operation and performance of the controller. Also, carefully read the operation and use manual of the tester to avoid damage to the test pattern caused by the abnormal operation of the tester caused by operation error and the test data is wrong.
2. Appropriate selection of test equipment. In order to ensure that the test is carried out normally, appropriate test equipment should be selected according to the different conditions of the test specimens, and a reasonable relationship between the test specimens and the effective volume of the test chamber should be maintained. For the test of the heat test sample, its volume should not exceed one tenth of the usable volume of the test chamber. For non-heatable test samples, its volume should not exceed one fifth of the usable volume of the test chamber. For example, when a 21 color TV is performing a temperature storage test, a test box with one cubic volume meet the requirements, but when it is ont, they can not meet the requirements. It should be replaced with a larger test Because the TV needs to dissipate heat during operation.
3. Place the test pattern correctly. The position of the test sample should be more than 10cm away from the wall of the thermal shock test chamber, and multiple samples should be placed on the same plane as much as possible. The sample placement should not block the air outlet and return air outlet, and a certain distance should be reserved for the temperature and humidity sensor. To ensure the correct test temperature.
4. For the environmental test that requires medium to be added in the test, it should be added correctly according to the test requirements. For example, there are specific requirements for water in the damp heat test box, and the resistance of the water in the test box should not be lower than 500 ohms. The general tap water resistivity is 10--100 ohms.m, the specific resistance of distilled water is 100--10000 ohms.m, and the specific resistance of deionized water is 10000-100000 ohm.m, so distilled water or deionized water should be used for moist heat test water, and be sure to use fresh water, because water is easily affected by carbon dioxide after contact with air and dust is polluted.Water has its owncapable of dissolving many substances. After a long time, the specific resistance decreases. Now there is a kind of pure water on the market. Economical and convenient, its resistivity is equivalent to that of distilled water.
5 Use of Hot and Cold Shock Test Chamber> The wet ball gauze (wet ball paper) used in the cold and heat shock test chamber requirements, can by no gauze should be substituted since the relative humidity reading is the difference between the root spacing and the temperature and humidity. In fact, it is also related to the local air pressure and wind speed at that time. The wet bulb temperaturebe refers to the amount of water absorbed by the gauze and the amount of water that evaporates from the surface. That depends on the situation. These are directly related to the quality of the gauze, so the weather dictates that the wet ball gauze must be a special wet ball gauze woven from flax It is difficult to ensure the accuracy of the wet bulb thermometer, that is, humidity. Correctly. In addition, the placement of the wet ball gauze is also clearly regulated. The gauze length: 100mm, tightly wrapped the sensor probe, the probe is 25-30mm away from the humidity cup, and the gauze is immersed in the cup to ensure the correctness of device control and humidity.