Rail Fastenings Systems

NABLA Evolution

NABLA Evolution is a direct rail fastening system that offers enhanced performance for tracks with tight radius curves. It has been proven in installations for several decades and is recognised for its simple installation and maintenance. By maintaining the track gauge, it significantly increases the life expectancy of assembly components.

Suitable for all track types, including heavy haul, NABLA Evolution offers improved electrical insulation and lateral force absorption. The unique use of
glass-reinforced material in the lateral insulator also offers increased mechanical strength.

Technical Features

  • An anchor screw is tightened to the contact, ensuring a consistent application of clamping force on the rail and a large range of torque. The high clamping force combined with the design of NABLA Evolution prevents rail roll.
  • The glass-reinforced material used in the lateral insulators creates a high level of mechanical strength and good lateral force absorption.
  • The system’s coach screw offers a large acceptable torque range of between 250 and 400 Nm. Toe load is achieved automatically once the screw is tightened to contact.
  • A good level of lateral adjustment is provided via the insulators to deal with track gauge and alignment. This allows fine gauge tuning by 1.25mm increment, ±7.5mm per rail seat.


  • As a result of its deep post insulator, NABLA Evolution offers exceptional resistance to wear caused by lateral loads. This reduces track maintenance overheads.
  • NABLA Evolution is simple to install, saving time and money.
  • The use of glass-reinforced material results in a high level of mechanical strength and good lateral force absorption.
  • NABLA Evolution offers higher electrical insulation than similar systems, making it an efficient, effective option.
Rail Fastenings Systems

NABLA Evolution