Self-Piercing Rivets

Rivet types

There are five families of Henrob self-pierce rivets. Each family is defined by unique geometry and has a range of macro features including head style, stem diameter and stem length. The five groups have been specifically developed to meet different functional requirements and application performances.

Rivet type selection

The choice of rivet type for a given application is dependent on numerous performance criteria. A rivet is selected, in conjunction with appropriate tooling, to match the application characteristics such as the examples listed below:

Head styles

Head styles are selected on the basis of either functional requirements or aesthetic appeal. Functional requirements may be:

• Head flushness (level with material surface)
• Shear, peel and fatigue strength
• Locator or mechanical stop
• Large bearing surface
• Attachment points for secondary parts

Countersunk head benefits:

• Flushness on the head side of the joint
• Good fatigue resistance

Flat, pan and dome head benefits:

Provides good peel strength, especially in plastics or thin sheet metals
Allows good head seating, especially when riveting thick or very hard materials
Accentuates the aesthetics of a riveted joint and/or covers surrounding indentation on a Class A surface

Special head styles

Special rivet head styles are supplied when there is a need to combine the functions of the self pierce rivet and an additional feature.

Rivet length and stem diameter

Rivet length is always matched to the stack thickness to be fastened. A given rivet length will cover a range of material stacks. Testing is carried out to determine the suitability of the rivet length for the material and thickness range being riveted. Henrob offers rivets in lengths of 4 to 14mm.

There are two standard diameters: 3mm and 5mm. The criteria for selecting the appropriate rivet diameter include:

• Required strength of joint
• Required robustness of joint
• Available access to joining area
• Material thickness and hardness

Manufacturing process

Henrob has a state-of-the-art rivet manufacturing facility that includes in-line wire processing, advanced multi-die forging technology with SPC control and 100% automatic inspection and packaging of finished rivets.

An aggressive R&D effort allows Henrob to offer the largest available range of self-pierce rivets and related products such as threaded studs, T-studs and stand-off location pins in various materials such as steel, stainless steel, aluminium, copper and brass. Dedicated R&D forging capacity facilitates the rapid development of new rivet geometries.

Rivet quality

Henrob's rivet design and manufacturing process are certified to TS16949 and ISO14001. Complete batch traceability exists from the production of raw material through to the packaged product.