May 18, 2022
Introduction
This article contains everything you need to know about vacuum chambers.
- What is a vacuum chamber?
- Types of vacuum chambers
- Industries that use vacuum chambers
- Tests and operations performed in vacuum chambers
1. What is a Vacuum Chamber?
A vacuum chamber removes air and pressure from a confined enclosure to test the effects of a vacuum on parts, materials, components, and assemblies. It can also be used to test the performance of applications for manufacturing operations. They are designed to withstand the type of pressure that is created by a vacuum and are capable of simulating environmental conditions where a vacuum may exist.
In the space and aerospace industries, vacuum testing is essential to determine a component‘s ability to withstand the pressure and vacuum of space. Other industries use vacuum testing to determine the stability of packaging that may be required to travel by air to different locations in the world.
In industrial applications, there is a need for high altitude testing, drying, and offgassing in controlled and replicable vacuum conditions and environments. These types of tests assist in establishing the quality and durability of a product.
2. Types of Vacuum Chambers
Vacuum chambers are designed to fit the needs of the industries they serve. This type of chamber can be benchtop for the testing of small parts or for use by small manufacturers. Other varieties can be the size of a room to test large aircraft parts and instruments for use in outer space.
As an offshoot of environmental chambers, vacuum chamber testing can be part of the processes available on a chamber designed to perform a wide range of tests from climatic conditions to the effects of high altitude. Though there are standard vacuum chambers, they can also be specially designed to fit a predetermined set of criteria.
Vacuum chambers are made in a variety of shapes and sizes. Standard vacuum chamber types are classified as box, spherical, cylindrical, D-shaped, and bell jar.
2.1. Box Vacuum Chambers
There are two types of cuboidal vacuum chambers, rectangular chambers and cubic or cuboidal chambers. The rectangular version of the vacuum chamber is designed for extreme vacuum (UHV), which can reach pressures as low as 100 nanopascals. The box-shaped vacuum chambers are capable of performing the full spectrum of vacuum testing, degassing, atmospheric testing, film deposition, and outer space simulation. Each type of box-shaped vacuum chamber has to be thick-walled with bracing to be able to withstand extreme pressure conditions.
2.2. Spherical Vacuum Chambers
Spherical chambers are used for surface testing, laser deposition, and UHV testing. The spherical shape allows for the adjustment of concentration from one point on the sample to multiple points. Spherical chambers are equipped with multiple ports to allow for several access entry points
2.3. Cylindrical Vacuum Chambers
The cylindrical vacuum chamber can be vertical or horizontal. The shape of the chamber is a determining factor in the chamber approach, where horizontal chambers can be accessed by openings at either end, while vertical chambers can be approached in a variety of ways, including lifting the chamber off its base. Cylinder chamber used for degassing or helium leak testing with an inner diameter of 100 to 2000 mm.
2.4. Bell Jar Vacuum Chambers
The bell jar vacuum chamber is similar to the cylindrical vacuum chamber with a welded dome top. They can be made from metal or Pyrex depending on the test type and product criteria. They come in a variety of sizes incorporating pads and feed collars. The bell jar vacuum chamber is used for high temperature applications. The Pyrex bell jar vacuum chamber is a transparent vacuum chamber mounted on a metal base plate.
3. Industries that Use Vacuum Chambers
A vacuum is a low-pressure space where all matter has been removed that could affect the test or production process. Using vacuum pumps, vacuum manufacturing industries test their products for leaks, durability and stability. Like the environmental chamber, the vacuum chamber provides valuable data and insight into a product's ability to make adjustments to improve product quality. Testing laboratories have been a huge step forward for the industry. They tell a company the parameters and limitations of their product, the information that is passed on to users and customers.
Manufacturing
The vacuum chamber is an essential tool in manufacturing. It provides data to ensure product safety and highlights any potential product flaws. Types of testing include leak determination or resistance to environmental conditions that may contain a vacuum.
One of the most damaging substances in the manufacturing process is moisture. By subjecting the product under production to a vacuum, moisture as well as microscopic air bubbles are eliminated. Another use of the vacuum chamber is the application of protective films, coatings and finishes.
Aerospace
The aerospace industry makes the most of vacuum chambers due to the nature of the environment their products are subjected to. Every aspect and part of an aerospace product must be inspected and retested to ensure safety and performance. This includes bolts, panels, switches, electrical components, fibrous materials, seat cushions, latches and door handles.
Agencies that oversee the production of materials used for spacecraft and aircraft have strict and strict requirements for the quality of the materials used. The vacuum chamber allows researchers to simulate adverse conditions and environments to determine the quality and limitations of ingredients.
The image below is a large vacuum chamber for testing parts and products for the aerospace industry. It is 7 meters high and 12 meters long with a temperature range of -180°C to 100°C.
Food and Beverage
One of the main concerns of the food industry is waste resulting from spoilage or poor environmental control. Food products that must be maintained at a specific temperature must be tested to determine their limits for quality assurance. In addition to helping to set boundaries for food products, vacuum chambers can also remove excess moisture and harmful gases from products that may contain contaminants. Cold storage is an important part of food transportation. The vacuum chamber aids in accelerating the cooling, freezing and drying processes to preserve the cell integrity, taste, color and appearance of the product. The food and beverage industry is heavily regulated by many agencies and organizations to ensure the safety of the public, which makes vacuum processing an important aspect of food production.
Biopharmaceutical Industry
The biopharmaceutical industry is one of the most closely watched due to the nature of the products. During production and development, precise decisions must be made regarding many aspects of the product, including shelf life, point of failure and susceptibility to environmental factors. Vacuum chambers are used in the biopharmaceutical industry for drying, degassing, sterilization, refrigeration, distillation and crystallization of drugs. They are also used to preserve specimens for research in an unpolluted environment as well as to aid in the creation of new drugs.
Solar Energy
The PV manufacturing process uses vacuum deposition chambers, a method for depositing a layer of substance, in the fabrication of solar absorber layers. In most cases, the process uses multiple cavities to move the substrate from one point to another. Moving the substrate from one chamber to another uses specialized conveying systems for high volume product production. The vacuum in each chamber should be at 10 to 9 mbar, which should be maintained for a long time. The PV panel manufacturing process uses larger and more powerful vacuum chambers.
Chemical
Vacuum chamber technology is a necessary part of chemical production for processes such as distillation, polycondensation, degassing and polyurethane production. The vacuum process for chemicals must maintain a constant pressure to avoid damage to the final product, which would render it useless.
The vacuum range for these chambers is from 1 to 10 mbar. The vacuum chamber reduces the heat load of the material, which is especially necessary for temperature-sensitive materials. The use of vacuum chambers in chemical production is a method of ensuring high quality and performance.