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Self-piercing riveting of sunroof framework



This sunroof, manufactured by a US sub-contractor for a Japanese vehicle manufacturer, is constructed from a moulded plastic front edge joined to aluminium extrusion side beams with steel cross members at the mid and rear positions. Due to the mix of materials used in the sunroof, it was very difficult to join the parts in an efficient, cost effective manner.

The conventional technique of using solid or blind rivets to join dissimilar materials was not considered suitable for a production rate of 500 sunroofs per day, and a fastening solution that could be easily automated was required.



Riveted joint between moulded plastic front and aluminium side beam. Note the extra material added around the rivet head

Following extensive research, the sub-contractor decided to adopt self-piercing riveting for the difficult front corner joint of moulded plastic and aluminium side beam, where high strength and good joint integrity were required. To increase the quality and strength of the riveted joints further, the sub-contractor made small design changes to the front moulding and aluminium side beam, which improved joint quality and also made automatic assembly of the sunroofs easier. The less critical joints between the aluminium side beams and steel cross members were made using clinching techniques, in an assembly station incorporating both joining methods.

Self-piercing riveting is now being adopted to manufacture an increasing range of sunroofs for various vehicle manufacturers.

Contact us for further information


Henrob Ltd
Second Avenue, Zone 2 Deeside Industrial Park,
Flintshire, CH5 2NX, United Kingdom
Tel +44(0)1244 837220
Fax +44(0)1244 837222
Contact Howard Litherland

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