BulbLock Rivets

BulbLock rivets are built for blind fastening applications where standard rivets may not provide enough backside support for thin, soft, or exposed materials. Designed for one-side installation, these watertight folding blind rivets help seal panels and joints against water intrusion while forming a broad blind-side bulb that supports the assembly from behind. For sheet metal, plastics, and composite materials, that larger bearing surface helps create a more secure joint with less concentrated stress at the fastening point.

What makes BulbLock rivets different is the way they expand during installation. PENCOM’s RBA BulbLock design forms a folding, multi-leg backside expansion, and official bulb/folding rivet references describe similar claw-style expansion and weather-resistant configurations used in panel, roofing, and profiled sheet applications. This style of blind rivet helps improve pull-through resistance, spreads clamp load across a wider area, and performs well in assemblies that may see vibration, movement, or outdoor exposure.

When backside access is limited but joint integrity still matters, BulbLock rivets offer a practical solution for enclosures, closed sections, panel assemblies, and other fastening jobs that benefit from blind installation and sealing-focused performance. Their wide blind-side footprint makes them especially useful where delicate or uneven substrates need better load distribution without sacrificing installation speed. For manufacturers looking for watertight blind rivets with strong blind-side support, PENCOM’s BulbLock category gives you a focused option for durable, production-friendly fastening.