Mechanical Fastening

Mechanical fastening is a widely used, cost-effective means of joining, which is particularly suitable for thin sheet sections. Fastening encompasses a range of processes that utilise a variety of fasteners including nuts & bolts, screws & rivets, or mechanical interlocks to assemble materials without heating. The high production rate techniques that have been studied at TWI include:

• Clinching - which uses a special punch and die to form a mechanical interlock between the sheet metals being joined
• Self-piercing riveting - in which a semi-tubular rivet is set using a punch and die to flare the rivet within the lower sheet so that no pre-existing hole is required.

Expertise

TWI's expertise in mechanical fastening spans sheet joining, plastics & composites and structural engineering. Industry benefits from a range of specialised support services, and consultancy and project work have included:

• advice on process selection
• research into effects of process parameters in clinching & riveting of sheet metals
• hybrid joints - fasteners plus adhesives
• mechanical properties of fastened joints

Resource

• commercial clinching & riveting equipment
• static, fatigue & impact testing equipment
• advice on best practice
• engineering design advice on machine-threaded fasteners
• materials science support

All TWI's confidential consultancy and project work is conducted to ISO 9001 quality standard.

View our resistance welding FAQs, Knowledge Summaries and Best Practice Guides.

For further information on any of these processes, please contact us.