Home 9 Projects 9 Southampton Freight Train Lengthening

Project Details

Date: 14 January 22
Categories: Interlocking, Rail
Client: S&C alliance via Colas Rail
Duration2017 - 2019

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Southampton Freight Train Lengthening

The aim of the Freight Train Lengthening Scheme is to provide enhancements to the existing rail infrastructure to allow longer freight trains, up to 775m to run between Southampton Docks and the West Midlands. This phase of the project will increase capacity at Southampton. For these works, OSL are conducting all designs through to GRIP 4 – 8. GRIP 4 has been successfully completed and GRIP 5 is currently being delivered to schedule. This includes all design works from Panel design, Trackside through to the design of the Smartlock data.


  • Increased capacity on the freight network. Freight trains up to 775m in length can now be accommodated within the signalling system.
  • Modification of the existing interlocking system, to create a more reliable and versatile system. This was achieved by moving the Trackside Functional modules into lineside location cases, which meant less failure points in the Relay interface.
  • New equipment provided which would aid maintenance and reduce costs. Including providing New LED Signal heads and signalling tail cables utilised a plug coupled dis-box when crossing the track.