A QBS is controlling the pressure of nitrogen for this high pressure leak testing application. A command signal is given to the QBS by a controller to go to the desired pressure. The part under test is submerged, thus bubbles will appear if there is a leak in the part.
The QBS series pressure controller is capable of controlling pressures from Vacuum to 500 PSI (35 Bar) with an accuracy of ±0.5%. The QBS can also be used to pilot volume boosters when more than 1 SCFM is required in the application. A second loop can be added when piloting volume boosters to improve repeatability and accuracy throughout the process.
While the pressure control in this application is very tight, the “water bath” technique is much less accurate and requires human decision making to determine if a leak is present. This technique is certainly acceptable and still widely used for many leak test applications, however, Proportion-Air can help with automating and improving this test.