Force Decay Leak Test
The force decay leak test is a non-destructive leak test method to identify leaks or weak seals in non-porous sealed flexible packaging. It is a deterministic method that gives quantitative and repeatable test results.
Force sensor technology is often used to test the integrity of medical device and pharmaceutical packaging including induction sealed bottles, medical pouches, sachets and bags, and flexible packs in the food & beverage industry.
How does Force Decay leak testing work?
A flexible package is placed within a tool set which comprises of a strain gauge load cell, which in turn is housed within a vacuum test chamber.
Vacuum is applied to the test chamber and under this vacuum the flexible package will expand and generate an expansive force in response to the vacuum.
The strain gauge load cell measures the expansive force over time to determine if the package has a gross leak, micron leak or has no leaks.
- If there is a gross leak, no expansive force is measured.
- If there is a micron leak, an expansive force is initially measured but will start to reduce over time as the pack lets air escape into the vacuum chamber.
- If the pack is good it will expand under vacuum and remain inflated and in turn generate a constant force measurement over time.
To ensure the integrity of the pack is not affected or does not burst, a force reaction/restraining plate is used to prevent full expansion.
What type of containers can be tested using force decay?
Force decay leak testing is ideal to test seal integrity of flexible packaging that contain solid or dry product.
As the principle of the test is based on applying force to expand the package, pack material needs to be flexible. Packaging such as pouches, sachets, bags, stick packs and lidded trays made of foils, films or laminates are ideal to be tested using the force decay method.