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Seal Lock® | Sealing Nuts
Bollhoff SEAL LOCK® | Durable Screw-in System with Maximum Sealing
SEAL LOCK® sealing nuts from Böllhoff are high-performance, one-piece fasteners designed to create strong, leak-resistant screw joints. They offer dual sealing—both at the internal threads and the flange surface—which generally provides reliable protection against gases and liquids, even under pressure. These sealing nuts are also quick and easy to install. The design typically retains the preload force even after repeated tightening cycles.
Double Sealing Action
Seals both inside the thread and under the nut head which helps avoid fluids or gases from leaking.
High Preload Force Retention
The metal-coated design helps prevent loss of clamp force when the sealing ring is in place.
One-Piece Construction
Simplifies handling and installation—no separate sealing element to install.
Reusability
Maintains sealing effectiveness and preload integrity even after multiple fastening cycles.
Materials & Coatings
- High-strength steel nuts
- Sealing ring integrated via metal coating
- Designed to maintain clamp force under the sealing layer
Size Ranges
- Available in common nut thread sizes (metric / unified)
- Multiple pitch options (fine/coarse)
- Special sizes may be available on request
Performance
- Temperature range: –40 °C to +110 °C
- Suitable for use in gas or liquid sealing applications
- Engineered for repeated assembly / disassembly
- Suitable for use in regulated applications or applications where safety is critical
Installation & Best Practices
- Use the correct torque as specified for the nut size
- Ensure the mating thread is clean, undamaged, and properly prepared
- The sealing function is active immediately upon tightening—no secondary sealing step is needed
- Periodically inspect the joint and retighten if required; SEAL LOCK® is designed to survive multiple cycles
SEAL LOCK® sealing nuts are suitable for demanding environments across many sectors:
- Automotive and e‑mobility systems
- Aerospace components
- Mechanical engineering and heavy machinery
- Rail transportation
- Medical devices and equipment
- Energy, oil & gas, and chemical industries
- Consumer appliances
In any setting where both structural strength and reliable sealing are required, SEAL LOCK® is an ideal fastening choice.
Ready to upgrade your sealing performance with a fastener you can trust? Bollhoff SEAL LOCK® sealing nuts available through Rivet Nut USA™, a division of Cardinal Components, Inc., deliver reliability and strength, along with watertight and airtight protection, demanded by today’s most challenging applications. As an authorized Bollhoff distributor, Rivet Nut USA™ offers expert support and fast turnaround times due to our stock inventory of SEAL LOCK® products that can be shipped directly to you. Contact our team today to request a quote, check availability, or get help finding the right configuration for your application!