Nabla RNTS and RNTC

What are the main differences between Nabla RNTS and RNTC? 

The main differences between the Nabla RNTS and Nabla RNTC rail fastening systems center on the type of sleeper they support and their internal assembly components. Both are classic STEDEF (Sonneville) fastening systems designed for noise and vibration reduction. 

Primary Differences

Shared Components

Both systems utilize the following standard components to maintain high clamping force and electrical insulation: 

• Nabla Elastic Clips: Provide constant vertical load.

• Screws/Coach Screws: Secure the assembly to the sleeper.

• Elastic Rail Pads: Help in vibration absorption.

• Protective Caps: Protect the fastening bolts from corrosion and debris. 

While both are STEDEF fasteners, the RNTS is used for flat sleepers and requires a cast-iron base plate, whereas the RNTC is designed for profiled (sloped) sleepers and typically uses rail insulators directly.