SYMPTOM POSSIBLE CAUSE
No Seal • Wrong material selection
for heat seal application
• Insufficient application torque
& Pressure
• Product Contamination on the container land
• Capping Problem
• Induction unit malfunction
• Induction unit set-up faults
Partial Seal • Insufficient application torque & pressure across land
area
•
Dimensional Mismatch between closure and container
• Product/ Moisture on container land seal
• Insufficient energy setting on induction unit
• Incorrect head coil position not uniform
• Capping problem
•
Off centre liner alignment
• Uneven Container land area
High Removal Torque • Excessive application torque
• Material back bonding closure
• Incomplete wax absorption / wax burning
• Excessive energy setting, holding time causing melting
• Oversize cut edge
Low Removal Torque • Insufficient
application torque
• Container finish melts down
• Dimensional conflict between closure and container
•
Excessive dwell time within induction field
Incomplete Wax Absorption • Insufficient energy
setting
• Insufficient dwell time within induction field
• Incorrect head coil position
• Product fills temperature
• Hot melt adhesive failure
• Product in contact with foil
• Coil too narrow for closure
diameter & undersized foil
Foil Corrosion • Wrong material for application
• Excessive energy setting
• Excessive dwell time within induction field
• Product on container land area
Back Bonding to Closure • Excessive energy setting
• Incorrect backing for application
• Melt point conflict between back and closure
Induction Sealing Process Flow:
Examples of Induction
Sealing wads:
For HDPE containers
For ALL containers
Liner Selection Criteria
Critical Induction Heat
Seal Parameters
