Dichtheitsprüfung
Leak testing
Leak testing is at home in many different industries, from the automotive sector to thermal or medical technologies, and is a crucial part of the quality control. Leak tightness is the decisive factor and criterion for a large number of products. We are concentrating on our core competencies in helium and ultrasonic leak testing.
Helium leak test
The helium leak test is a fast and process-reliable semi or fully automatic test method that can be used for reliably detection and localization of even very small leaks. And that both in the laboratory and in large-volume series production.
Ultrasonic leak test
The universally applicable ultrasonic leak test is the new dimension of gas bubble detection in the water bath. This is an objective, worker-independent, semi or fully automatic leak test method for industrial series production. A particular advantage is that the leakage points can also be automatically localized very precisely.
Leak testing systems for series production
Various sensors are used for leak testing in series production. An extremely important point is that in leak testing procedures, it is not uncommon to mention the detection limit of the sensor but not the detection limit or detectable leakage rate of a leak testing system or device. The determination of the leakage rate of a leak testing system always depends on the respective application and test object. There are several methods in the field of leak testing. Which leak test method is the right one always depends on the type of application. The following overview shows the most frequently used sensors and their detection limits.
Procedure
Helium vacuum
Helium atmosphere
Ultrasonic
Sensor
Mass spectrometry
e.g. Wise TechnologyTM
Ultrasonic probe
What is measured / detected?
Current 10 – 15 A.
2 ⋅ 10–10 A
Air bubble < 0,1 mm Ø
Detection limit
10–12 mbar ⋅ l/s
10–6 mbar ⋅ l/s
10–8 mbar ⋅ l/s
(Idealized examination in a laboratory measuring unit)
Procedure
Sensor
Helium vacuum
Mass spectrometry
Helium atmosphere
e.g. Wise TechnologyTM
Ultrasonic
Ultrasonic probe
Procedure
What is measured / detected?
Helium vacuum
Current 10 – 15 A.
Helium atmosphere
2 ⋅ 10-10 A
Ultrasonic
Air bubble < 0,1 mm Ø
Procedure
Detection limit
Helium vacuum
10–12 mbar ⋅ l/s
Helium atmosphere
10–6 mbar ⋅ l/s
Ultrasonic
10–8 mbar ⋅ l/s
(Idealized examination in a laboratory measuring unit)
Procedure
Sensor
Hydrogen
Semiconductor sensor
Pressure difference
Pressure sensor
Worker examination
Eye
Procedure
What is measured / detected?
Hydrogen
Electricity
Pressure difference
1 – 0,1 Pa
Worker examination
Air bubble 1 mm Ø
Procedure
Detection limit
Hydrogen
10–6 mbar ⋅ l/s
Pressure difference
10-4 mbar ⋅ l/s at 1 Pa, 0,1 l volume and 10s
Worker examination
2,6 x 10–5 mbar ⋅ l/s in 20s
Procedure
Helium vacuum
Helium atmosphere
Ultrasonic
Sensor
Mass spectrometry
e.g. Wise TechnologyTM
Ultrasonic probe
What is measured / detected?
Current 10 – 15 A.
2 ⋅ 10-10 A
Air bubble < 0,1 mm Ø
Detection limit
10–12 mbar ⋅ l/s
10–6 mbar ⋅ l/s
10–8 mbar ⋅ l/s
(Idealized examination in a laboratory measuring unit)
Procedure
Hydrogen
Pressure difference
Worker examination
Sensor
Semiconductor sensor
Pressure sensor
Eye
What is measured / detected?
Electricity
1 – 0,1 Pa
Air bubble 1 mm Ø
Detection limit
10–6 mbar ⋅ l/s
10-4 mbar ⋅ l/s at 1 Pa, 0,1 l volume and 10s
2,6 ⋅ 10–5 mbar ⋅ l/s in 20s
Procedure
Hydrogen
Pressure difference
Worker examination
Sensor
Semiconductor sensor
Pressure sensor
Eye
What is measured / detected?
Electricity
1 – 0,1 Pa
Air bubble 1 mm Ø
Detection limit
10–6 mbar ⋅ l/s
10-4 mbar ⋅ l/s at 1 Pa, 0,1 l volume and 10s
2,6 ⋅ 10–5 mbar ⋅ l/s in 20s
