White Paper

Understanding Ultrasound Technology To Inspect Pouch Seals

Source: PTI Packaging and Inspection Systems

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Application Note: Understanding Ultrasound Technology To Inspect Pouch Seals
Product Sheet: Seal-Scan™ — Seal Integrity Testing
PowerPoint Presentation: Seal-Scan™ 525 Defect Gallery

A pouch seal is a structural element that joins flat film material, and a component designed to close a pouch airtight. Traditional test methods e.g. peel strength or burst, can measure the joint strength of the seal, using destructive methods. However, this type of testing is often unreliable. A strong seal is not necessarily an airtight one, and the flow of gas or liquid through the seal (leak) is just one type of seal defect. As such, there is a fundamental challenge to any leak testing method, whether it is a fish tank-bubble, vacuum deferential, or helium test: none of these methods detect non-leaking seal defects.

No physical theory conclusively links the transparency or reflectivity of pouch material to seal quality. Yet, visual inspection methods e.g. human vision (ambient light) or machine vision (IR, UV, laser), are still widely used. The assumption is that defects are visible (at least if transparent material is used to make a pouch). Point of fact is that vision based inspection is inherently unreliable as it fails to recognize invisible defects and falsely rejects properly sealed pouches that exhibit cosmetic irregularities.

Click Here To Download:
Application Note: Understanding Ultrasound Technology To Inspect Pouch Seals
Product Sheet: Seal-Scan™ — Seal Integrity Testing
PowerPoint Presentation: Seal-Scan™ 525 Defect Gallery

PTI Packaging and Inspection Systems