TRIAD Technologies, Inc.

Leak and Flow Testing

Leak testing equipment is a type of nondestructive testing equipment used to measure the escape of liquids, vacuum or gases from sealed components or systems. Some configurations require a separate leak detector or sensor as an input. They are often equipped with various other components such as pumps, calibrators, gauges and cases.

In the mass flow method, any pressure change measured by a pressure sensor is compensated for by inputting air into the test part. The amount of air that enters is measured by a flow sensor, directly determining the leak rate of the part. Leakage flow is directed across a heating element. The temperature change across a temperature transducer bridge results in an output voltage proportional to mass flow. Another method is the mass spectrometer method. This process involves the pressurizing of the test object with a helium mixture inside an airtight pressure chamber. The air is then evacuated from the chamber, creating a pressure gradient between the internal volume of the part and the vacuum. The helium molecules move out of the part through any leakage. A mass spectrometer then samples the air inside the chamber and measures the partial pressure of helium. The pressure differential or decay method involves the initial inflation of the test object and the establishment of a reference pressure. After a designated amount of time, the pressure is measured again and the initial and final measurements are compared. The change in pressure can be used to calculate the leak rate given the internal volume of the device. Pressure decay is able to detect minute changes in pressure.

Leak and Flow Testers