FP - Seal Defects (Compressed)

Classification 

  • A major defect if:
    1. There is visual evidence of seal overheating, such as bubbles or exposed foil
    2. There is less than 3 mm (3/32-inch) of continuous good seal (non-delamination)
  • Is considered a minor defect if:
    1. There is some visual evidence of seal overheating, such as bubbles or exposed foil
    2. There is more than 3 mm (3/32-inch) of continuous good seal

Identification 

A compressed seal is any separation of the laminated plies in the seal area. The material bond strength is questionable in the area of the defect.

Causes 

  1. The sealing bar settings were not correct during sealing (i.e. excessive temperature, pressure and/or dwell time).
  2. Material bond strength is inadequate.