April 20, 2022
5. Components of an environmental test chamber
The first consideration when choosing an environmental test chamber is choosing one that will last for a long time, which can be ensured by having a good understanding of the chamber's internals. Since different types of chambers perform different functions, there may be variations in the types of features and structures. All test chambers shall have certain basic components to meet specified requirements..
5.1. Internal workspace: Internal partitions should be welded to reduce the risk of leaks. Nail baffles do not completely seal and will leak heat and moisture.
5.2. Doors: Doors should have gaskets. The best and most common form is the silicone form because silicone can withstand changes in humidity and temperature, which is important when carbon dioxide and nitrogen are used.
5.3. Exterior: The outer body of the chamber shall be welded with cold rolled heavy gauge steel as the steel retains its shape and is highly durable. To increase the life and durability of the cavities, it is recommended to apply a powder coating to protect against rust and corrosion.
5.4. Machine components: Depending on the application of the chamber, different types of equipment such as heaters, coolers, condensers, evaporators, controllers, sensors and other modules are used depending on the application. depending on the type of medium produced. Heaters, compressors, refrigeration units, dryers and other equipment must comply with regulations established by the International Organization for Standardization (ISO) as well as by national regulatory bodies.
5.5. Insulation: The interior and exterior partitions of the chamber vary by application but shall be insulated. Insulation must have a very low K-factor such as fiberglass or mineral wool and be fireproof, non-corrosive and meet health and safety standards.
5.6. Sensors and displays: Older test chambers had a simple on and off switch. All recent models have digital monitoring sensors and data loggers. The digital controller allows for manually creating setpoints and making adjustments, helping to correct errors and interruptions. The sensor should be thermistor sensor for best accuracy.
5.7. Computer interface: The computer interface allows the Mbyte data transfer rate. Pie chart recording provides the ability to collect real-time data and documents related to the test process and is directly connected to the controller.
5.8. Safety features: Each test chamber shall have a set of safety features including high temperature safety controls, thermomechanical fuses, high temperature limiters, noise reduction systems and alternative power supplies. position.
6. Types of environmental test chambers
There is a wide range of test chambers designed to meet specific environmental requirements. The most common types of test chambers are humidity and temperature, which can be separate or combined. Some other chamber types are altitude, climate, cryogenic, Halt and Hass, pressure, remote control, spray, vacuum and stability.
Below are the types of environmental test chambers:
- Agree test chamber
- Altitude test chamber
- Climate test chamber
- Cold chamber
- Dry chamber
- Environmental test chamber
- HALT & HASS . test chamber
- Humidity chamber
- Pressure chamber
- Salt spray chamber
- Stabilization chamber
- Temperature chamber
- Thermal shock chamber
- Vacuum chamber
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6.1. Agree test chamber
The Agree test chamber is a combination of temperature and humidity conditions with vibration conditions. They create rapid changes in temperature, humidity. Along with that is a shock test to measure the response of the product when it is transported or moved to determine if the product can withstand the transport.
6.2. Altitude test chamber
The aircraft industry uses altimeter chambers to train pilots and provide them with an experience of hypoxia or hypoxia. These chambers improve training sessions as no protective gear is required and eliminate the need to take the practitioner to a height, which saves on training costs. Altimeter chambers, pressure relief chambers, can generate pressure and gas conditions at different heights to determine adjustments and changes to product design.
6.3. Climate test chamber
Climate chambers create different climatic conditions to see the effects on the product. Climatic chambers create conditions such as thermal shock, extreme temperatures, altitude, humidity, radiation, corrosion, and many more. Test pieces can be small enough to sit on a counter or large enough to walk in and use video to observe the test specimen during testing.
6.4. Cryogenic Chambers
As the name implies, cryogenic chambers create conditions with extremely low temperatures. Using liquid nitrogen or helium, a typical cryogenic chamber can reach temperatures as low as -238°F or -150°C. The use of a cryogenic chamber is time-consuming and expensive because the temperature must be lowered very much. slow to avoid the product experiencing heat shock.
6.5. Dry Rooms
A dry chamber, sometimes called a desiccant dry chamber or a type of environmental test chamber. Inside the dry chambers, the humidity does not exceed dew point 14, or the humidity falls below 1% relative humidity. They are insulated, sealed and leak-proof. Because they are hermetically sealed, they always maintain not only low humidity but also good particulate filtration. Dry chambers are most commonly used in: medical device manufacturing, lithium battery manufacturing, automotive composite manufacturing, and pharmaceutical manufacturing and packaging.
6.6. Environmental chamber
Environmental chambers, also commonly known as environmental test chambers and sometimes referred to as climate chambers, are test chambers that assess the quality and reliability of a product. To do so, the chambers reproduce certain environmental conditions in an enclosed space, where they monitor and evaluate the long-term impact of these conditions on the product inside. Common environmental conditions that chambers simulate include normal and extreme pressure, altitude, temperature and humidity. By subjecting products and equipment to extreme environmental conditions and changes, manufacturers are able to capture and correct weaknesses and flaws before they reach the markets they have intended. choose.
6.7. Environmental Testing
Environmental testing is the measurement of equipment performance under specified environmental conditions. The chambers fully simulate temperature and humidity test conditions. Some cavities even cause corrosion through salt spray into the cavity. Environmental test chamber includes salt spray test chamber, high and low temperature test chamber, constant temperature and humidity test chamber, UV aging test chamber, xenon lamp aging test chamber, test chamber ozone aging and ovens. The main function of the environmental test chamber is to see how the product behaves when operating in different environments.
6.8. HALT and HASS Testing Chambers
HALT and HASS testing is performed to identify design weaknesses, improve product reliability, and reduce lifecycle costs. During HALT testing, a product is emphasized beyond its design parameters to identify weaknesses and flaws in the design phase. It is often repeated many times and the product is exposed to a variety of environments. HASS testing is performed during the production phase to identify manufacturing method flaws using the same stress tests used during HALT testing.
6.9. Humidity Chambers
The humidity chamber creates humid conditions to determine the product that is subject to corrosion, warping, biological growth and the potential for cracking. The data obtained from the tests allows designers to develop reliable and cost-effective solutions. Can produce a wide range of wet conditions from 10% to 100%.
6.10. Pressure Chambers
The pressure chambers test the product under different peak pressures and can withstand high and low pressure conditions. Chamber operation must be carefully monitored to avoid fire and malfunction. They can simulate static and variable pressures at high altitudes and pressures at different ocean depths. Atmospheric pressure in the chamber can be up to 60,000 psi or reduced to create a vacuum.
6.11. Salt spray chamber
The salt spray chamber, known as the salt mist test, tests a sample's resistance to corrosion. The test item is placed in the test chamber and subjected to highly corrosive solutions applied by means of a pressure nozzle. The purpose of the test is to provide data on the durability of the surface or coating of the product. The longer the product is used without corrosion, the more durable it is. Regardless of the severity of the salt spray test, test results cannot be used to predict a product's response to the actual environment.
6.12. Stability Chambers
Stability chambers provide a stable, controlled environment where all variables are held constant as others are modified to test specific effects. They are primarily used to test temperature and humidity ranges but can do shelf life testing.
6.13. Temperature chamber
The temperature chamber is the most common type of environmental test chamber. They generate different temperatures to simulate the types of temperatures the product will encounter, and measure and evaluate the product's response to different temperatures. A temperature chamber can also be used to store products that require a stable environment.
6.14. Thermal shock chamber
The thermal chamber is a form of the temperature chamber. Their purpose is to simulate conditions with sudden or drastic changes in temperature and to measure the amount of stress and tension those conditions place on a product. Liquid or air is used to generate the temperature variances. Test objects can be immersed in a non-toxic, non-flammable and low-viscosity liquid or placed between compartments to induce temperature changes. The three-zone method brings the item to room temperature between tests. The type of method depends on the test sample.
6.15. Vacuum chamber
The vacuum chamber removes air and pressure from a sealed chamber to assess the effects of the vacuum on the material. Product testing in a vacuum is a requirement of regulations related to the aerospace and defense industries. Spacecraft engineers use vacuum testing for the spacecraft's electronics, circuits, lenses, filters, and structural materials. The vacuum chamber is also used to remove air bubbles from the plastic pellets that are about to be introduced into the mold.