TWI provides a number of services relating to the welding of polymers, including training, mechanical testing and non-destructive testing of the joints, troubleshooting and expert advice.
We have built up an extensive knowledge base covering all plastics welding processes, and all thermoplastic materials, including thermoplastic elastomers, and pioneered the development of innovative techniques that provide improved quality and greater productivity.
We can offer impartial advice on the most appropriate joining technique for any application or thermoplastic material. These welding techniques include ultrasonic welding, hot plate welding, hot gas welding, extrusion welding, high frequency welding, friction welding (including spin welding and vibration welding) and laser welding. The choice of which of these methods to use depends on factors such as part size and complexity, required cycle times and material.
Expertise and Equipment
TWI's technical excellence and equipment is made available to Members in the following ways:
- Welding equipment and expertise for all processes, including process selection, joint design and development and validation of welding procedures
- Non-destructive and destructive testing for plastics welds, including a specialised whole-pipe tensile rupture test rig
- Process review and optimisation
- Failure investigations
- Personnel who combine many years' experience with cross-industry-sector knowledge and contacts
- Plastic welder and weld inspection training and qualification via our industry training and certification programme
- Advice on industry standards
Applications that involve welding plastics range from assembly for mass-produced domestic appliances to fabrication welding of pipelines and storage tanks, and from high-speed welding of films and fabrics to precision welding of medical devices.
Technology Challenges
Current technology challenges being focused on at TWI include:
- Welding of dissimilar materials – dissimilar plastics and plastics to other material
- Three-dimensional welds
- Welding high-temperature polymers
- Lifetime prediction of welds
- Welding of technical textiles
- Welding of wood
- Digitalisation of plastics welding processes
- Development of flaw acceptance criteria