Requirements of ultrasonic welding for integral plastic parts

Requirements for plastic parts by ultrasonic welding include:

1. Structure of plastic parts

Plastic parts must have a certain rigidity and sufficient wall thickness. Too thin wall thickness has a certain risk. It needs to be pressurized during ultrasonic welding. Generally, the air pressure is 2-6kgf/cm2. Therefore, the plastic parts must not be deformed under pressure.

2. Material of plastic parts

Ultrasonic welding also has certain requirements for the materials of the two plastic parts and the positioning of the two plastic parts.

3. Sharp corner if the stress of an injection molded part is very concentrated, such as sharp corner, it will break and melt under the action of ultrasonic wave. In this case, R angle can be added at the sharp angle.

4. Ultrasonic welding is the required welding line

The design of the welding line is related to the firmness and aesthetics of the plastic parts after welding

5. Design of contact surface of welding head for plastic parts injection molded parts can be designed into any shape, but ultrasonic welding head can not be made at will. The shape and length may affect the frequency, amplitude and other parameters of the welding head. The design of welding head needs a reference plane, that is, the reference frequency plane determined according to its working frequency.

6. The thin and curved transfer structure in the plastic part is in the shape of the plastic part contacted by the welding head. If there is a thin and curved structure and it needs to be used to transfer ultrasonic energy to the transmission chamber, especially for semi crystalline materials, it is difficult to transfer ultrasonic vibration to the processing surface. This design should be avoided as far as possible.