Process Validation for Induction Sealing
It is an all time recommendation to have process validation for induction sealing to safeguard the sealing performance due to many variables that could easily change the performance of an induction machine.
A slight change in the induction machine sealing power setting, product conveyor speed, guide rail settings, sealing head angle or sealing head height can all have significant influence on the amount of energy the induction seal will receive; resulting in failed seals.
Visual Inspections: Induction Sealing Process Validation
Even the most competent and capable operators on your production shifts have to rely on opening product to make visual inspections and perhaps a very good memory of how warm the cap should feel immediately after passing through the sealing head.
Manual validation is more anecdotal than value based “validation” of your induction sealing process and machine set-up. The LinePatrolman™ range provides you with that numerical and repeatable process validation measures. The measure is a calibrated reading to record the energy that would be transferred to products passing through the machine.
Some Things to Look for in a Good Seal:
- Correct Settings – An experienced operator would know to look for a concentric heat pattern in the foil; by holding the foil to a light source at the correct angle he would see a smaller circle where material has not been affected by heat. This means the seal has heated from the outside inwards in an even pattern; hence an even seal.
- Overheating – there are a number of factors to show if there has been overheating including – visual discolouration of one or more layers of the induction foil, bubbling or creasing, a flattening of the bottle neck, melting of a backing resealing foam (when present).
- Uneven heat sealing –The foil can look well sealed but an uneven heat seal can result in areas of the seal being too firmly “welded” or very lightly welded making the seal likely to fail with a little pressure on the side walls of the bottle/container.