The Pioneer of Modern Leak Testing

Force Decay Leak Test

What is a Force Decay Leak Test?

The Force Decay leak test is used to test the seal integrity of a flexible or semi-rigid package that contains a headspace. It is well suited to test non-porous package material such as films, foils or laminates. The test package is placed in a vacuum chamber between two plates, one of which is connected to a force sensor. The chamber is evacuated at the start of the test and the flexible package will expand until the package reaches an equilibrium state with the internally applied pressure. Over a measured time, the force applied to the sensor will remain constant indicating a good seal or the force will decrease, indicating a leak in the package seal.

How is a Force Decay test performed?

First, the test package is placed in chamber and the chamber is evacuated to a set pressure. Next, the flexible package expands putting pressure on the force sensor. A timed step checks for decay in the force being exerted on the force sensor. No decrease in the force on the sensor indicates good package integrity and is a pass rating. A measured decrease in force indicates a leak or test failure.

Force Decay Test Pneumatic Diagram
Force Decay Test Pneumatic Diagram

Which Uson leak testers perform Force Decay 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

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