Uson has published a new application note titled Sealed Component testing. The application note describes how to leak test componets which have no openings or ports to attach to your leak tester.

In the sealed component test the test piece is placed inside a chamber constructed in such a way that its volume is only slightly greater than that of the test piece. Tip :A single chamber can be used to test different sized and shaped components through the use of volume reducing infills or filler blocks.


A metered volume of air is dumped into the chamber which is connected to the leak tester. If the test component is leak-tight, the change in pressure is due to the dead volume, and will therefore be minimal and will pass the test. If the test component has a large leak, the resultant drop in pressure is larger and therefore will fail the test.

The new application note provides complete details of the test including diagrams and it may be downloaded by joining Uson's free Literature Club at