The aluminum casting shell of high-voltage SF6 switchgear often forms blisters due to casting defects, and the leak hole structure is complicated and difficult to clean. Once it leaks, it is difficult to find the leak point using conventional methods. This system adopts helium mass spectrometry leak detection technology to perform integral leak detection on the cast shell. It has many advantages such as high detection accuracy, fast tempo, and good reliability, which effectively guarantees product quality.