User manual

Bio-inert Quaternary Pump User Manual 103
Test Functions and Calibration
8
Leak Rate Test
Initially, the pressure is increased to about 100 bar below the target pressure,
which has been set for the test.
Then piston 1 is brought to its rear position. An increasing flow is delivered by
piston 1. In case of a leak, the pressure will drop initially as long as the flow
rate delivered by the piston is lower than the leak rate. As soon as the flow
rate of the piston exceeds the leak rate, the measured pressure will increase
again. Therefore the minimum pressure of that curve segment corresponds to
the flow and leak rate at that time and the leak rate is measured. Compare to
the description of the system pressure test “System Pressure Test” on page 97.
Subsequently, piston 2 is moved to its rear position, then piston 2 delivers and
the measurement is done as described for piston 1.