How to use the Optimal Sealing Head for Your Dispensing Cap

Not all caps are created equal—and neither are induction sealing heads. In this video, Enercon’s Jessica Toellner demonstrates why selecting the correct sealing head for your cap style is essential to achieving a consistent, high-quality seal.

The Challenge: Sealing a Dispensing Cap with a Flat Sealing Head

We’re working with a dispensing style cap, which has a taller profile than a standard flat cap. The key difference? The liner sits significantly lower inside the cap, creating more vertical distance between the top of the cap and the sealing surface.

We attempted to seal this dispensing cap using a standard flat sealing head, keeping all other settings constant. After allowing the liner to cool, we inspected the seal.

The Result? No seal. The flat sealing head simply couldn’t deliver enough focused energy to heat the liner effectively. This was because the induction field wasn’t able to reach the liner due to the added height and recessed placement of the liner.

The Solution: Deep Tunnel Sealing Head

This is where application-specific tooling becomes essential. For tall dispensing caps Enercon offers a Deep Tunnel Sealing Head—engineered to direct the induction field deeper into the cap, closer to the liner’s location. For this sealing head you want to align the foil liner in the cap with the labels on the sealing head. We then attempted to seal the same dispensing cap with the Deep Tunnel Sealing Head under identical line conditions.

The Results: A Strong, Reliable Seal

After the liner cooled, we inspected the new seal:

• Complete adhesion across the land area.
• No signs of underheating or misalignment.
• A clear success—demonstrating the importance of matching your sealing head to your cap geometry.

Key Takeaways

• Use a Flat Sealing Head for standard flat caps with liners near the cap’s surface.
• Use a Deep Tunnel Sealing Head for tall caps (like Yorker or sports caps) where the liner is recessed inside the cap.
• Always confirm proper alignment for the sealing head you are using as guided by the labels on the sealing head

Need Help Selecting the Right Sealing Head?

At Enercon, we specialize in helping optimize induction sealing operations for maximum performance and energy efficiency. Whether you’re working with unique cap designs or troubleshooting seal issues, our team is here to support you and help you Achieve a Perfect Seal™

Watch the full video to see the sealing comparison in action.