Helium Mass SpectrometerLeakDetector (Helium Mass SpectrometerLeakDetector) is a gas industry term, using helium or hydrogen as a leak indication gas, and using a gas analyzer to detect helium and leak detection mass spectrometer. Helium gas has low background noise, low molecular weight and low viscosity coefficient, so it is easy to pass through the leak hole and diffusion. In addition, helium is an inert gas that does not corrode equipment, so helium is often used as a leak indication gas. This gas is sprayed into a container that is connected to a gas analyzer (adjusted to react only to helium). If there is a leak in the container, the analyzer will react, so as to know where the leak is and the size of the leakage.

Helium mass spectrometry leak detection technology is an indispensable technology in the field of vacuum leak detection, because of high leak detection efficiency, simple and easy to operate, sensitive instrument response, high precision, not easily affected by other gases, has been widely used in resistance furnace leak detection. Helium mass spectrum leak detector is a gas tightness detection instrument based on the principle of mass spectrometry, which uses helium as leak indication system. The mass spectrum chamber is composed of ion source, analyzer, collector, cold cathode ionization gauge, extraction system and electrical part. The electrons emitted by the filament in the mass spectrum room oscillate back and forth in the room and collide with the gas in the room and helium gas entering the room through the leak hole to ionize them into positive ions. These helium ions enter the magnetic field under the action of the accelerating electric field and are deflected by the Lorentz force to form a circular arc orbit. By changing the acceleration voltage, ions of different masses can be detected through the magnetic field and the receiving gap to the receiving pole. Helium injection method and helium absorption method are the two most commonly used methods of helium mass spectrometry leak detector in resistance furnace leak detection.