Principle of tube welding:

The high frequency ultrasonic vibration can generate instant thermal energy to make it possible to weld the contact surfaces of PE plastic tubes or plastic laminated tubes, so as to achieve the tube sealing purpose.

Advantages:

• Only local heating at the tube end sealing position and the filler inside of the tube will not change its physical and chemical properties during the high temperature tube sealing process.
• The tube sealing surface is very smooth and free from any overflow of the plastic material.
• Any oily, greasy and impurity contamination can be removed during the high frequency ultrasonic welding process. Therefore, a clean and neat tube sealing effect can be achieved.

Principle of tube welding:

Use a small electric heater to contact with the sealing portion of the plastic tube for rapid heating so as to melt the contact parts.

Advantages:

• The thermal energy will not be transmitted to the filler, and the filler inside of the tube will not change its physical and chemical properties during the high temperature tube sealing process.
• The tube sealing surface is very smooth and free from any overflow of the plastic material.

Principle of tube welding:

Use high temperature to blow the hot air inside the tube opening, then use a pliers to seal the tube end.

Disadvantages:

• During the heating process, the hot air flow will be sucked off by the negative pressure, but still certain heat will enter into the tube, thus it will change the temperature of the filler inside the tube, even the property of the filler inside will be damaged.
• The tube sealer shall be supplied with cooling water to cool down the hot air nozzle, therefore, it will be inconvenient to move the tube sealer.
• Nowadays, for packing biochemical products and for packing high quality products, almost no manufacturer in Japan, Europe and USA is using the hot air sealing method.

Principle of tube welding:

Use an electric heater to heat up a metal plate. As soon as the metal plate is heated up to become red color, put the metal plate close to a plastic tube (approx. 1~2 mm). By means of the radiation heat transfer, part of the plastic tube end will be melted, then use a pliers to seal the tube end. This is a traditional tube sealing method.

Disadvantages:

• The filler inside the tube is very easy to get damaged due to the rapid increase of high temperature;
• Easy to get a plastic overflow at the joint of the tube seal, causing a bad appearance of the welded product.