Plastic tube sealing: If you are a manufacturer looking to introduce a new product range that needs to be packaged in a plastic tube, then you need to decide which type of seal you will need for your plastic tube to keep the product contained safely, kept in perfect condition, and looks presentable for your end customer.
MSD plastic tube filling machines come in a range to meet your needs, so whether you want hot-jaw sealing, ultrasonic sealing, hot-air sealing or impulse sealing, we can help!
Your choice of plastic tube sealing option will also depend on the type of plastic material you are using to make your tubes and if they are made of pure plastic or they contain a combination of plastic and metal for extra strength and durability.
Some plastic tube sealing machines are specifically designed to work with plastic-only tubes, so make sure you choose the right machine to suit your needs.
Let’s take a closer look at your tube sealing options and their advantages and disadvantages.
This is a sealing option that is suitable for plastic-only tubes and works with a system where heated metal jaws clamp the end of the plastic tube together and apply heat to allow the plastic to melt together creating an airtight seal.
Hot jaw plastic tube sealing is considered to be less effective than high-frequency sealing but is fine for most products dispensed by a tube.
The main advantages of using this method of tube sealing are that the seal is flat and looks very neat. As it is only the contacted areas of the tube that are heated, the overall structure of the tube remains perfect and the integrity of the tube filling remains stable and unaltered by the process.
This method of tube sealing is by far the safest choice if you are using aluminium laminated tubes for your product.
The sealing process involves creating an eddy current in the aluminium layer of the tube. The current acts to heat up the aluminium layer, which then will cause the plastic tube layers to heat up too.
Once the tube reaches the correct temperature to melt the plastic element of the tube, sealing clamps are closed over the end of the tube allowing the melted plastic to mesh together. The end of the tube is then cooled forming a tight seal.
The main disadvantages of high-frequency plastic tube filling are that your inner tube filling may be negatively affected due to the heat created by the current flowing throughout the tube.
For those wanting a very presentable tube seal, there can be a risk over over-melting of the tube end that doesn’t give a smooth appearance.
This is a sealing solution that is suitable for both plastic-only and aluminium laminated tubes. The process works by heating the internal plastic and melting it through high-frequency friction force emanating from the ultrasonic horn.
Once the plastic has melted, clams will close the tube ends and cool the plastic to form the seal.
The main advantage of using this method is that only the contact areas of the tube are heated. This means that the integrity of your tube filling product is kept stable and unchanged.
The process gives a nice flat seal and over-melting is tightly controlled. This type of seal is more effective and reliable. It is especially good for tubes with oily fillings as the high-frequency oscillation action will drive away oils from the seal, giving a more effective seal.
One of the most popular choices for plastic tube sealing is the hot air sealing method. This is suitable for plastic-only and aluminium laminated tubes.
This process involved heating the inner seal area of the tube using hot air. The tube end is then pressed tightly together and cooled to form the seal.
The only disadvantage of this method is that there is a small degree of hot airflow going into the tube that can raise the inner temperature of the tube filling. So this isn’t a good choice if you are manufacturing heat-sensitive or biochemical products.
If you need more information, do not hesitate to contact our friendly and experienced team at MSD to discuss your plastic tube sealing needs. We are here to help!