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What techniques can I use to weld nylon?


Frequently Asked Questions

There are many techniques (over 20) for joining plastics including:

  • Adhesive bonding
  • Solvent welding
  • Mechanical/snap fits
  • Hot plate welding
  • Hot bar welding
  • Impulse welding
  • Hot gas welding
  • Extrusion welding
  • "Flashfree" or BCF
  • Vibration welding
  • Spin welding
  • Ultrasonic welding
  • Friction stir welding
  • Resistive implant welding
  • Induction welding
  • Dielectric welding
  • Laser welding
  • Infrared welding
  • Microwave welding

The most commonly used methods for nylon are spin, vibration, dielectric and ultrasonic welding. Laser welding and non-contact infrared have also successfully been used. The choice of process is affected by the form of the material- moulded component or film

The key issues specific to the welding of nylon are:

  • Check which type of nylon it is as there are several types.
  • Nylon is hygroscopic, therefore injection mouldings require 'drying' in an oven at 60°C overnight prior to welding.
  • Nylon is semicrystalline, with a sharp melting point. To ensure successful ultrasonic welding, mouldings need to be carefully designed with the appropriate joint configuration.
  • Glass-filled nylon produces a fine swarf during frictional welding processes such as spin or vibration welding. Flashtraps need to be designed into the mouldings.
  • To dielectric weld nylon film, it may be necessary to preheat the welding tool to about 45-50°C. This helps to raise the temperature of the nylon above its T g (glass transition temperature), giving it the capacity to flow and hence to weld.

See further information about plastics welding and testing or please contact us.

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