The thermal shock test chamber, also known as the "high and low temperature shock test chamber" or "temperature shock test chamber", is a common environmental testing equipment in laboratories and production units. It is used in the metal, plastic, rubber, electronics and other industries to test the degree to which materials can withstand continuous extremely high and low temperatures in an instant, so as to detect chemical changes or physical damage caused by thermal expansion and contraction of the sample in the shortest time. Let's see how to choose it and what are the requirements for installation?
How to choose
The thermal shock test chamber needs to simulate the sudden change of hot and cold temperature during the test, and has strict requirements on product quality and selection. Only products with excellent quality and matching functional performance can better serve the high and low temperature shock test. So what are the skills and selection requirements when we choose the thermal shock test chamber?
1. Test chamber size selection
Choose the appropriate inner box size of the hot and cold shock test chamber according to the size of your own product. On the market, the conventional capacity of hot and cold shock test chambers is 50L, 80L, 100L, 150L, 225L, 408L, 800L, 1000L, etc. We should choose the capacity based on long-term testing needs. For example: now we need to make a plastic product with a volume of 200*300*400mm, and the company may develop a new product with a volume of about 350*450*550mm in the future. Then we will choose a hot and cold shock test chamber with a capacity of 150L based on the size to be made in the future.
2. Temperature shock range selection
According to the relevant test standards of your own product materials (national standard / European and American standard), select the appropriate temperature shock range of the hot and cold shock test chamber, generally -40+150; -55+150; -70+150. Of course, you can also choose different shock ranges for different products.
3. Two-box vs. three-box selection
How to choose? The two-box shock only has the highest temperature and the lowest temperature shock, while the three-box shock has a normal temperature transition in the middle. This means that there is no normal temperature transition for the product, which is more destructive and has more stringent requirements on the product.
4. Air cooling or water cooling selection
Water cooling and air cooling each have their own advantages, and choosing which one is better depends on your specific needs. In short, air cooling is affordable, simple in structure, and easy to install, which is more suitable for daily needs; while water cooling has good heat dissipation effect, low noise, and long life, which is more suitable for high-performance scenarios.
5. Safety and reliability
The various protections, warning measures and safety interlocking devices of the hot and cold shock test chamber should be complete and reliable to ensure the safety of the test personnel, the tested products and the thermal shock chamber test equipment itself. Environmental test equipment must have the characteristics of safe operation, convenient operation, reliable use and long working life.
6. High or low repeatability
A thermal shock chamber environmental test equipment may be used for multiple tests of the same type of product, and a tested engineering product may also be tested in different environmental test equipment. The stress level (such as thermal stress, vibration stress, electrical stress, etc.) of the thermal shock chamber test product is consistent with the requirements of the same test specification.
In short, when purchasing a thermal shock test chamber, you need to consider many factors and make a choice based on your needs and budget.
Installation Requirements
Thermal shock test chambers are essential testing equipment for aviation, automobile, home appliance, scientific research and other units. They are suitable for safety performance testing of electronic components, reliability testing, product screening testing, etc. In order for the high and low temperature test chamber/thermal shock test chamber to fully play its role and achieve the best state during operation, there are certain requirements for the installation of the equipment. What are they specifically?
1. Installation site requirements:
The environment of the thermal shock test chamber has a direct impact on its efficiency. The installation location should consider the heat dissipation efficiency of the machine and easy inspection and maintenance.
- Set it on a flat and vibration-free ground (please check with a level);
- The ambient temperature should be maintained between 10-25 so that the machine can achieve the best stable operation;
- There should be at least 60 cm distance between the test chamber and the wall and any other machine;
- The thermal shock test chamber should be away from heat sources and flammable and explosive substances;
- The equipment should not be exposed to direct sunlight and maintain indoor air circulation;
- Please avoid setting it in places with antibodies and dust;
- The power supply line and water supply and drainage pipelines should be shortened as much as possible.
2. Installation matters of power distribution works:
- Do not connect the ground wire to the oil or gas pipe;
- Please ground the rear ground terminal. The ground wire must be properly constructed. According to the technical standards for electrical equipment, the third type of grounding project, the grounding resistance should be kept below 50 ohms;
- Pay attention to the power capacity. Do not use one power supply for multiple machines at the same time to avoid voltage drop, affecting machine performance, or even causing malfunction and shutdown;
- If you connect the ground wire to the water pipe, the water pipe must be a metal pipe that is connected to the ground (and all metal pipes can be effectively grounded).
3. Installation precautions
- Please use a dedicated switch for the power switch, and do not use the same plug as other electrical machinery. Do not place the soft wire on the floor or in a humid place to avoid being stepped on or leaking electricity. A coupling transformer should be installed in places where the power voltage is too low to increase the voltage to the rated value, so that the compressor motor will not burn out due to the low voltage and cannot be started.
- There should be a good ventilation space behind the hot and cold shock test box to allow the condenser to play a heat dissipation effect. Avoid direct sunlight and stay away from heating elements such as stoves to avoid affecting the freezing effect. During the test, the operating door cannot be opened for a long time to avoid water mist in the box.
- The internal and external materials of the hot and cold shock test box are made of high-grade stainless steel, but places with running water and humidity can easily cause adverse effects on the machine parts and electronic control center and reduce efficiency, which should be avoided as much as possible.
- The test box cannot be installed upside down, and must be placed horizontally on the floor to make the operating door of the temperature test box easy to open and reduce the noise during mechanical operation.
- The inside of the warm and hot shock test box should be kept clean at all times. When cleaning the outer box, you can apply a little varnish and wipe it with a soft dry cloth. If it is too dirty, use a neutral detergent and clean water to clean it. The back or walls are easily covered with dust, and the heat dissipation of the condenser should always be paid attention to.
