The leak detection system of ultrasonic detector is different from the specific gas sensor, which is limited by the specific gas it is designed to sense, but detects by sound.
Any gas passing through the leak hole will generate eddy current and have ultrasonic wave band, so that the leak detection system of the ultrasonic detector can sense any kind of gas leakage.
When scanning with the leak detection system of ultrasonic flaw detector, you can hear the missing sound from the earphone or see the change of digital signal. The closer you get to the leak point, the more obvious it is. If the site environment is noisy, rubber pipes can be used to reduce the receiving area and shield the antagonistic ultrasonic waves.
Strain gauges are also commonly called resistance strain gauges. Wire strain gauge, foil strain gauge, semiconductor strain gauge, etc. The strain gauge whose resistance changes with deformation is attached to the surface of the specimen in the specified direction, and the resistance of the strain gauge changes with the surface strain of the specimen. People use a highly sensitive galvanometer to measure the change of resistance. The change of strain value is deduced from this. Strain gauges are widely used to test the mechanical properties of materials, such as measuring the tensile modulus of materials, which is obtained by calculating the applied load and the strain measured by strain gauges attached to the surface of specimens.