
How Anderson Dahlen Maintains the Integrity of Custom Vacuum Chambers
Posted on: September 28, 2017
Here at Anderson Dahlen, we take immense pride in the quality construction of our pressure vessels, vacuum chambers, and other create custom vacuum chambers with a ten-foot diameter, or even larger, while still including a variety of flanges, ports, doors, and other features as needed. Of course, the more features that are added to a vacuum chamber, the harder it can be to maintain true seals. We’re sometimes asked how it is we guarantee the integrity of our custom vacuum chambers. The answer is quite simple: quality fabrication and helium leak testing. 
How Helium Leak Testing Ensures the Integrity of Our Vacuum Chambers
Helium is the method of choice for testing custom vacuum chambers for several reasons:
- Helium is found only in trace quantities in the atmosphere, making it relatively easy to detect even from tiny leaks.
- Helium is lighter than air, further increasing the ease of detection.
- Helium is still currently widely-available and inexpensive to obtain.
- Helium (in these small quantities) is non-toxic, non-corrosive, and otherwise presents no significant danger to technicians or machinery.
So, the process for testing for leaks in a custom vacuum chamber is relatively simple.
In these tests, the helium detector is placed within the chamber, which is then pumped down to a vacuum. Helium is sprayed around the welds and seals. If any is seeping into the chamber, the detector lets us know.
We can also conduct the opposite test, to verify for leaks from the chamber. The chamber is fully emptied, outgassed, and cleaned to ensure it’s free of contamination. Then it’s filled with helium. A medium-strength mass spectrometer tuned to helium is then passed around the vessel, checking all welds and seams, for any evidence of higher-than-normal helium levels.
We can also provide an RGA test, which samples the environment inside the chamber under vacuum and gives specific qualitative data as to the partial pressures and total pressure inside.
These processes are what allow us to reliably create vacuum chambers capable of standing up to the rigors of space research and other scientific work, even custom work such as the very large vacuum chamber we recently completed for the University of Colorado.
Turn to Anderson Dahlen For the Best Vacuum Chambers and Custom Pressure Vessels
For over seventy years we have produced the best in custom equipment, pressure vessels, and vacuum chambers for scientific and industrial use around the country. Contact Anderson Dahlen today to discuss your specific project needs.