ultrasonic welding of plastic mouldings Advice : inserting, spot welding, staking & swaging

Ultrasonic welding is a fast, clean and efficient method of assembling plastic mouldings.  Based upon your mouldings and needs, different ultrasonic welding methods can be used to join plastic to plastic and plastic to metal - replacing or eliminating the need for solvents, adhesives or mechanical fasteners.

 

Below is an overview of each ultrasonic welding method. To gain the most from this advice, it should be used in conjunction with our ultrasonic welding guide which lists the most common unfilled grades of plastic available & their suitability for each of the ultrasonic welding methods - ultrasonic inserting • spot welding • staking • swaging / forming.

 

METHOD	BEFORE	AFTER
Inserting - Ultrasonic embedding of metal components like inserts into preformed holes in the plastic moulding. Ultrasonic inserting produces high strength welds with no stress build up at high speed and enables reduced plastic moulding cycles.
Spot Welding Ultrasonic spot welding produces high strength welds and is particularly good for large parts and those with complicated geometry or hard to reach joining surfaces.
Staking Ultrasonic staking produces welds with good appearance at high speed and is good for tight assemblies.
Swaging / Forming Ultrasonic swaging / forming produces welds with good appearance and reduced stress build up at high speed and can be used to overcome material memory.
Welding - Ultrasonic assembly using a vibrating metal tool (horn) at 90° to stationery plastic mouldings which vibrate. When combined with pressure, friction heats & melts the plastic mouldings which solidify at the contact point once the vibrations stop, thus creating the weld. Ultrasonic welding produces very high strength welds at high speed. With suitable plastic moulding and joint design, air tight seals are possible.

For more advice on plastic mouldings view our ultrasonic welding materials & plastic material selection guides