How Bulb-Tites Work

What is a Bulb-Tite® rivet?

Bulb-Tites rivets are a high performing fastener that differ from other structural rivet types due to their load spreading tri-star anchor and EPDM washer; providing a weather & vibration resistant seal with a large blind side bearing area. 

A specialised structural rivet that spreads the clamping force through its anchor blades whilst providing excellent pull through resistance; making them an ideal choice for safety anchor points, and in the fabrication of pantech & refrigerated truck bodies. Bulb-Tites are renowned for their extended material grip range, enabling a single rivet to cover a greater range of material gauges including curved or uneven surfaces. Check out the rivet blog to understand structural rivets .

How to install Bulb-Tite® rivets.

Pre-drill the correct diameter hole. 

Use the correct nose tip & jaws. 

Blind side Tri-Star anchor. 

Bulb-Tite Installation Process.

Installing a Bulb Tite is very similar to a standard  rivet, however it is important to have the correct nose tip and jaws for a professional finish.

  • Rivet body is inserted into the pre-drilled hole.
  • Rivet-Tool pulls the pin & head into the rivet body.
  • Blind side anchor is formed.
  • Breaking force is reached pin breaks at notch.
  • Blind rivet is set & clamps parts together. Easy huh!

How do Bulb-Tite® rivets work? 

Bulb-Tite structural rivets work a little differently to standard rivets, as there is an internal mechanism that locks a portion of the pin (mandrel) inside the rivet's body. This creates an additional layer of material that assists in increasing the rivets strength, whilst interlocking with the material and creating their inner strength.  When installing a Bulb-Tite, the slotted body folds and splits into a propeller shape blind–side anchor. The diagram below provides a four step overview of the process. 

How to install Bulb-Tite® rivets correctly.

The diagram below shows correct & incorrect Bulb-Tite placement. It's important to have sufficient blind side space for the slotted body rivet to fold and bend in the propeller shape anchor blades.   

Recommended Bulb-Tite® Rivet Guns.

*Gesipa PowerBird Pro Gold

* Requires optional extra 17/48 (7252237) Gesipa Nosepiece for 7.7mm

Correct Bulb-Tite® Rivet Installation.

  • The stem can be seen just above or just below the top (max 5mm below).
  • The rivet has "bulbed out" correctly.
  • The rivet is sealed off correctly.
  • It is recommended that silicone is applied if the rivet is 3mm or more below.
  • If you are unsure, double check by looking at the seal under the rivet. If it is squashed and the rivet feels tight then it has bulbed out correctly.

Incorrect Bulb-Tite® Rivet Installation. 

    • The stem is too far below the surface.
    • The rivet has NOT ‘bulbed out’ correctly and therefore has no strength.
    • The rivet is not sealed off adequately which could pose potential leak issues.
NOTE: The cause of this is often due to the ‘bulb’ not being able to expand out as it clashes with the side of the roof sheet. The rivet must go into the centre to avoid this happening.