WHAT IS ULTRASONIC TECHNOLOGY
It is a sophisticated welding method, which allows joining two different parts in one single part without using chemical reagents or glues.
The ultrasounds work molecularly with the polymers of the thermoplastic material. It is necessary to have a small percentage of these polymers to obtain a perfect result out of this technology.
The direct consequence is that it is possible to use ultrasonic welding in a wide range of application fields.
HOW ULTRASOUNDS WORK
Some key elements are necessary to weld perfectly the two parts: at the very first step, the high-frequency and low-amplitudevibrations play the major role, generating heat, which is going to melt the plastic component on its interface.
These frequencies, undetectable for the human hear, are called ultrasounds.
The placement of the parts during the welding process can be manual or automatic, according to the application; one of the two parts lays on a static fixture, while the correspondent part is exposed to the sinusoidal ultrasonic vibration, which is perpendicular compared to the contact area.
The friction obtained from the vibrations causes heat, which will change the structure of the plastic polymers of the two parts, mixing them together.
Once the polymers are cold, their new structure is stable: in this way, the weld is created.
New systems are available, offering the possibility to set the welding time, the amplitude ad, most important thing, the amount of energy delivered in the contact area of the two parts, from a computer.
In this way, it is possible to obtain an optimal welding.
Normally, an energy generator, a converter, a booster and a sonotrode(or horn) compose an ultrasonic machine.
Ultrasonic generators can reach frequencies up to 20 kHz.
The converter, which contains piezoelectric ceramics, transforms the electrical frequencies in a mechanical movement.
The mechanical movement reaches first the booster, which literally increases the amplitude of the movement (amplitude of the vibration) and finally the sonotrode.
Being in direct contact with the material, the sonotrode allows the vibrations to reach the two parts to be welded.
Like every machine tool, according to the kind of application, also ultrasonic equipment can be a source of noise.
Every ultrasonic welder branded Sonic Italia are designed to pass the threshold of human hearing (1700-1800 Hz).
The big penetration of the plastic material in every technological sector (automotive and components industry, white goods industry, electrical industry, medical industry, military industry) has created a big variety of applications.
Different measures of protection must be prepared and applied in case of machines generating noise:
- Earmuff (individual protection, local noise)
- Protection applied on the welding tool (local noise)
- Sound proof cabin (collective protection, high level of noise)
The machines branded Sonic Italia do not generate any kind of radiation.
The noise caused by the machine is due to a mechanical-acoustical effect of resonance of the air, which generates sound waves. (Law. 89/392 att. 1 step 1.5 parag. F)
In any case, according to the statistics, only 15-20% of the applications cause an high-level noise.
Sonic Italia can provide technical advice end, if necessary, collaborate study of soundproofing, thanks to its net of suppliers and high-qualified technicians.