Mass flow:

The mass flow method fills the part to be tested from a prefilled reference volume (ReVo). After a balancing phase, the balance flow caused by a possible leak between the connected volumes is determined at the end of the measurement time.

Differential pressure method:

With the differential pressure process, either the pressure drop or the pressure rise can be measured. The part to be tested is filled with compressed air or it is evacuated. At the end of the filling process, the test chamber is separated from the filling unit and the pressure change in the sample that occurs during the measurement time is measured. If the part to be tested is leaking, the pressure will decrease over time in the sample. In the case of vacuum tests, the leaking part is detected by a pressure in the sample that increases with time.

Volume flow:

If workpieces are to be tested for a defined flow rate, the volume flow rate is used. Typically, the flow rate method is used for tubing, pipes (fuel pipes) and valves (e.g., ball seat valves); the flow rates are usually relatively high.

Back pressure and/or blockage test:

Here, the back pressure is measured on workpieces. By means of this measurement, you can check whether a borehole has been drilled with the correct diameter or whether a channel in a casting that cannot be seen optically has a constriction.

Pressure rise:

The workpiece to be tested is filled with compressed air by another leak test module (differential pressure or mass flow) and a measurement is carried out from the inside to the outside. After the measurement, the workpiece remains filled and is not vented (measurement 1). The pressure rise module then fills the surrounding space to a higher pressure. A possible leakage is detected over the course of time by an increasing pressure in the workpiece (measurement 2); the test direction this time is from the outside to the inside.