Abstract: Leakage is one of the most frequent failures of high-pressure heater in nuclear power plants. As an important part of CI, high -pressure heater plays a key role in determining the smooth and stable operation of the equipment. This paper mainly introduces the application of helium leak detection and vacuum differential pressure leak detection in heat transfer pipe and seal welding of high-pressure heater, which can largely improve the efficiency of testing and repairing.

Key words: high-pressure heater, helium leak detection, vacuum differential leak detector