Answers to the most common questions and doubts about induction sealing.

What is induction sealing?

Induction sealing is a method for hermetically sealing containers by means of heat microwaves, that is, without contact. A threaded mouth container, a plastic stopper and a suitable liner for the induction of that plastic container are required, in addition to an induction sealing machine.

How is induction sealing performed?

The induction sealing method is very simple: the liner must be placed inside the stopper with the metal face up. Then the container is closed and induction sealed. If the thread and cap fitting is good and the the material has been correctly chosen, the liner will be sealed to the container mouth.

How can a glass container be induction sealed?

The three key elements for a successful glass container induction sealing are the following:

1) The kind of glass. It is not true that all glass containers can be induction sealed. There are certain glass containers with a specific composition that makes induction sealing impossible. It is important to know the composition of our glass: our manufacturer will provide it.

2) The lid or stopper. Usually, stoppers for glass containers are metallic and metal or aluminium is incompatible with induction sealing. The stopper for a good induction sealing must be made of plastic and must make secure contact with the container mouth.

3)  Not all induction materials can seal glass. A material suitable for sealing glass must be chosen. CSP has a wide variety of materials to induction seal glass.

What are the problems for a good induction sealing?

If the induction material is suitable, it is most likely that the problem is the thread-stopper fitting. Even if it is a plastic stopper, it is likely that it is not intended for induction sealing and does not meet one of the essential requirements for a good induction sealing: the contact with the container mouth. If the stopper, with its bottom, does not make contact with the container mouth, the liner will not have the necessary pressure to be sealed.