Nabla RNTC Clip for Elastic Fastening Systems

What is Nabla RNTC Clip?

The Nabla RNTC clip is a high-performance trapezoidal spring blade used in elastic rail fastening systems, specifically designed for urban transit (trams/LRT) and specialized track technology. 

The Nabla RNTC rail fastening system is a classic STEDEF fastener fixed onto a profiled concrete sleeper using elastic clips, rail insulators, screws, elastic rail pads and protective caps. 

Technical Specifications

• Material: High-grade alloy spring steel( 60Si2MnA or 60Si2CrA).

• Clamping Force (Toe Load): Exceeding 16 kN (approximately 2500 DaN) once the anchor screw is tightened to contact.

• Durability & Fatigue Life: Up to 3 million cycles (for standard models) or up to 200 million cycles (for advanced variants like Nabla C1) without breaking.

• Hardness: Heat-treated to a hardness range of 42–47 HRC (standard) or up to 55 HRC for specialized high-load applications. 

Application & Compatibility

• Rail Types: Optimized for grooved rails common in tramway systems, including 60Ri1, 60Ri2, 62Ri1, and 62Ri2.

• Track Environments: Versatile installation in concrete, asphalt, and natural stone paving, as well as green (grass) track beds.

• System Integration: Paired with reinforced nylon 66 (PA66) insulators to provide high electrical insulation (>10 K Ohms). 

Key Benefits

• Vibration Reduction: Effectively dampens ambient noise and vibrations, making it ideal for residential urban rail lines.

• Gauge Stability: Its design prevents rail roll and maintains precise track gauge even in tight radius curves (down to 40m for some models).

• Installation Efficiency: Features an optimized coach screw with a wide torque range (250–400 Nm), allowing for automatic toe load application once tightened to contact.