What is Vibration welding technology

Vibration welding is based on ultrasonic principle, is more suitable for big size product welding. As the restriciton of ultrasonic welding which can’t do big dimension welding. Vibration welding adopts high frequency vibration to weld two plastic components together.

Working flow:

1.Put the components waiting for welding to fixture/jig/mold , and install the fixture to the vibration welding machine.

2.After mold installation, technical engineer adjust the welding parameters according to welding requirements and material . Such as vibration frequency , time, vibration direction and so on.

3.Confirm the parameters setted, put the 2 parts to upper and lower mold separately.

4.Press double start button, the safety door closed, vibration welding machine start working, when temperature up to melting point and also the function of pression, the 2 plastic parts can melted together.

5.Welding time is about 15s, but also decided by product. upper /left/lower/right mold open, at the same time, safety door open.

6.Operator get out the welded compoent, vibration welding cycle finished.

Specific points: vibration use the principle of friction melting, vibrate one of 2 pressed plastic parts, the other do alternating motion , the displacement can up to 1.8mm or 4mm, the distance is called amplitude, the friction frequency is 100Hz or 240Hz, so friction heat caused.

In this process, one of two parts are welded, put on the platform of machine with pressure fixed clamp, and the other parts are placed on the driven plate driven fixture, generally speaking, the lifting platform is perpendicular to the vibrating head make lifting movement, can let two parts contact, powered by a hydraulic cylinder, hydraulic system pressure control, the two parts must be by the lifting platform pressure clamping force pressure together, in the process of welding and keep the whole, the clamping force of continuous function on the two plastic parts, under the compression state vibration head at the same time, after a few seconds or more than ten seconds, the plastic welding friction heat production, and welding,This time is called “welding time”, after which the molten plastic is cooled and cured for a short time under pressure, this time is called “holding time”, and finally the vibrating head stops vibrating, the lifting platform descends and returns to its original position.

In this process, one component is clamped on fixed fixture, the other component is clamped on driving fixture. Normally, lifting plate do lifting motion which can make 2 parts weld together, the power is supplied by hydraulic cylinder, the pressure is controlled by hydraulic system. The 2 parts must clamped by pressure of lifting plate , during welding and fixing process, clamping force will always on the 2 parts.

October 29, 2020