Using high-power ultrasonic generator and high-power transducer, titanium alloy horn, the sealing effect is stable, and the trimming surface is smooth and does not scratch. Stable and reliable performance and long life. The ultrasonic mold is oxidized by electroplating, which is more durable and has a more beautiful appearance.
Applicable to: plastic hoses for various materials such as toothpaste, cosmetics, oil, food, industrial supplies, etc.
Q: What’s the ultrasonic welding system include?
Ultrasonic generator, transducer and horn.
Ultrasonic plastic welding machine with high power, the generator signal adopts phase-locked frequency automatic tracking circuit, so that the output frequency of the generator is basically consistent with the resonant frequency of the transducer.
(1)The generator used in the ultrasonic plastic welding machine with power above 500W adopts a self-excited power oscillator and also has a certain frequency tracking capability.
The acoustic system for an ultrasonic plastic welding machine consists of three parts: 1 drive part 2 fixed part 3 working part. In the above three components, the drive is the core, generally using a longitudinally vibrating transducer clamped by a bolt, wherein the half-wavelength longitudinal vibrator and the quarter-wavelength longitudinal vibrator, the half-wavelength longitudinal vibrating and the half-wavelength concentrator The connections form a full-wavelength plastic welding transducer, and the quarter-wavelength longitudinal vibrator is connected to a quarter-wave concentrator to form a half-wavelength transducer.
(3) Tool head
Different tool heads are required for different welding objects. Whether it is near-field welding or transmission welding, only a half-wavelength tool head can achieve the maximum amplitude of the welding end face. The tool head has two types with amplitude amplification and no amplitude amplification. The tool head of the acoustic system for plastic welding machine is usually made of aluminum alloy. The end face is plated with hard alloy. When the power is high, it is also made of titanium alloy material. The fatigue strength of the material is more than double that of aluminum alloy.
Effect of plastic humidity on ultrasonic welding：
Humidity Defect: Humidity defects are generally formed during the process of making streaks or loose plastic parts. Humidity defects attenuate useful energy during welding, so that the sealing position seeps and lengthens the welding time, so the plastic parts with high humidity should be dried before welding. deal with. Such as polyoxymethylene.
Release agent and impurities have a certain influence on ultrasonic welding
Although ultrasonic waves can shake off solvents, impurities, etc. on the machined surface, they should be removed as much as possible for sealing or high strength. In some cases, it is necessary to clean the plastic parts first.
The ultrasonic welding strength of recycled plastics is relatively poor, and the adaptability to ultrasonic welding is also poor. Therefore, if recycled plastics are used, various design dimensions should be considered as appropriate.
The shelf life of the plastic also affects the welding effect:
After the plastic parts are injection-molded, they are usually placed for at least 24 hours before welding to eliminate the stress and deformation of the plastic parts. Plastic parts that are molded from amorphous plastics may not meet this requirement.
For both composite films, there is an optimum weld pressure value. The heat sealing strength of the welded joint begins to increase rapidly with the increase of the welding pressure. When the pressure exceeds 150 N, the heat sealing strength of the joint rapidly decreases as the welding pressure increases. Because the lower welding pressure can not make the contact surface tightly combined, there is a large area of air. Under the action of ultrasonic waves for a certain period of time, most of the ultrasonic vibration is lost in the air, the interface friction is not sufficiently heated, and the formed fusion area is not. Uniform, the joint heat sealing strength is not high. When the welding pressure reaches a certain value, it can be considered that the interface is tightly combined and the interface temperature rises rapidly. The pressure is favorable for the diffusion of the polymer chain, and the welded joint region forms a dense structure, and the heat sealing strength also increases within a certain range. However, the welding pressure is too high, the extrusion flow of the molten polymer is accelerated, the polymer chains are arranged laterally along the welding surface, and the edge thermal stress concentration is intensified, causing brittle fracture of the welding edge. In addition, the welding pressure is increased, and the edge of the metal horn is liable to cause damage to the film, resulting in a sudden decrease in the heat sealing strength.