The Pioneer of Modern Leak Testing

Air Flow – Mass Flow Leak Testing

(Chinese Translation)

What is Air Flow or Mass Flow Leak Testing?

Mass flow or air flow testing uses flow measurement devices to calculate leak rates based upon the rate of air flow through the device. This technique is suitable for small and large volumes and is often applied to test kitchen appliances, gas meters, exhaust systems and other products where gas or air is required to flow through the item.

As a leak testing technique, mass flow measurement is very useful for detecting small leaks in large volumes. When selecting a mass flow tester it is important to select the correct flow meter range to ensure that the desired amount of sensitivity is achievable. Uson’s leak test application engineering group are available to help you with this.

How does a Mass Flow – Air Flow Leak Test Work?

The product is attached and the test is started. Air moves into the inlet port and the precision micro-thermistor (T1) measures the temperature of the inlet air.

The flow sensor’s heater (H) increases the temperature of the moving air far above room temperature as measured with the sensor T3.  

Outgoing air temperature is measured at the next precision micro-thermistor, T2.

A temperature difference of T2 minus T1 is proportional to the ability of the air mass to transfer heat. The read out is in mass flow units, such as SCCM.

Mass Flow Air Flow Test Diagram
Mass Flow – Air Flow Test Diagram

Which Uson Leak Testers Can Perform Mass Flow and Air Flow Leak Tests?

Optima vT – A versatile and customizable leak tester with up to two channels and eight sensor inputs that supports pressure decay, differential pressure, mass flow and other common tests

Qualitek – Fast, sensitive and accurate pressure decay, differential pressure and mass flow leak testers

Sprint – Small foot print single or multi channel pressure decay and flow testers

Vector – Uson’s most powerful and configurable leak and flow tester, fully customizable pneumatics, up to ten independent test channels supporting a wide variety of input sensors

Uson Innovative Systems (UIS) – Custom made manual, semi automatic and fully automatic leak test systems and fixtures

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