Plastic to Metal Bonding

This photograph shows the ball end of a metal hook being induction heated just before it is inserted into the plastic body of a coat hanger.Typically, the heating time is less than one second.  Heating the ball or serrated end of the hook prevents splitting of the plastic body.  Additionally it holds the hook in a fixed orientation.  

This is important for the garment manufacturer particularly where garments are moved around by conveyor on their hangers.  By applying a little twisting force to the hook, it can be released allowing it to be orientated in any direction, whilst still allowing the hanger to take the full weight of a heavy garment.  This is of course beneficial for the end user.

TV and Audio Speaker Grille Bonding

Induction bonding of steel speaker grilles into plastic and high density polystyrene TV bezels, offers major benefits to the manufacturer.  The principle advantages being that it is a fast, one shot operation that produces a uniform bond that is vibration free and stronger than glueing or ultrasonic staking. Typical plastic to metal bonding machine used for simultaneously bonding two metal speaker grilles in to a TV bezel. The system works by rapidly heating the edge of the metallic grille. The grille is then pressed home by pneumatic cylinder. 

The heat energy is so localised that the visible painted area of grille remains unaffected and the cosmetic, all important appearance of black, white or coloured surfaces is maintained.

Left shows a section through a bezel and the depth of metal penetration into the plastic body is self evident.  In fact the bond is so strong that once bonded, destructive force is needed to separate the components. The "floor to floor" process time to produce this incredible bond is around 8 seconds.

This method of bonding is also used in other applications ranging from assembly of cameras through to bathroom cabinets.  We also manufacture equipment for inserting studs and threaded inserts.We also manufacture equipment for plastic and rubber de-bonding and have supplied equipments for de-bonding rubber and plastic casters, fork lift truck tyres, military tank tyres, engine mounting brake shoes and many other items where a quick method of reclamation is required.

Syringe Bonding

To overcome the potential problem of a syringe needle becoming disassociated from its plastic hub, we have developed an equipment that bonds the two parts together.  The needle is lightly abraded in the joint area and once assembled the joint area is induction heated and a very strong plastic to metal bond is created.

This photograph shows a twin station needle bonding machine.  Needles are hand loaded onto a small fixture, typically five at a time (as shown above) and the fixture is loaded into the bonding machine. 

When the operator closes the sliding door the needles are automatically raised to the heating position for bonding.  Whilst one side of the machine is heating the other side can be loaded/unloaded. 

The heating time for most plastic to metal bonding applications is in the order of 0.5 seconds to 6 seconds.   We also manufacture equipment for catheter tip forming.  Please contact us for more information.

Medical Products

This plastic to metal bonding application for medical sampling brushes involves the induction heating of the twisted wire section.  Once heated, the wires are pressed into the plastic tube and a permanent bond is produced.This same process can of course be used for a variety of applications ranging from screw driver handles through to cosmetic products.

For other metal bonding applications, please contact our head office, our  Technical Sales Staff  will be pleased to help you. 

updated: 13/10/2006

© 1997-2008 Cheltenham Induction Heating Limited

Phoenix Works, Saxon Way, Cheltenham, Gloucestershire GL52 6RU England

Telephone: 00 44 (0)1242 514042 - Facsimile: 00 44 (0)1242 224146

Email: sales@cihinduction.com

updated: 25/06/2008