Packaging – burst testing
How we test seal strength in retort pouches and lidded trays – a test used by the packaging manufacturers and food and drink producers for quality control and troubleshooting. 2.02 mins
Burst testing is used to determine seal strength and a pack's ability to withstand transportation and handling. It's particularly used for retort pouches and tray and lidding applications. We would expect clients that produce retort pouches or plastics to use this test, along with manufacturers of ready meals and retort processed foods.
The pack to be tested is placed between restraining plates. The needles from the compressed air line are inserted into the pack via septum. Compressed air is uniformly injected into the pack and this is recorded, as is the time taken for the pack to inflate.
As the pack inflates, the force acting on the upper and lower body of the pack are balanced by the reaction force exerted on the plates. The plates are there to maintain a constant angle. And without these, the pack would take a pillow shape and the seals would peel from the inside.
The pack bursts and this indicates if there are any defects or weak areas in the seal, or just gives a reading of the strength of the seal. The pressure is recorded at the point at which the pack bursts.