Four Lines Modernisation (4LM)

Project name: Four Lines Modernisation (4LM)

Location: London, United Kingdom

Company/client: Transport for London / London Underground – Principal contractor – Thales GTS

Tratos & Transport for London / London Underground cooperation

In the largest project of its kind, Tratos has supplied more than 1,400,000 km of axle counter cable, low voltage signalling power and control cable to Thales GTS for its Transport for London/London Underground Four Lines Modernisation (4LM) project.

Tratos designed a range of fully compliant cables to meet all the required electrical, physical and fire safety code of practice demands without compromising the safety critical signalling and control systems. Its LSZH compounds, which were used for the insulation and outer sheath, had to comply with LU S1085 A4 (Fire safety materials code of practice) and the operational cable service life of 40 years.

To deliver the benefits as early as possible, the network has been divided into 14 ‘Migration Areas’ for a carefully phased rollout. The first five of these are centred on the Circle line and improvements will go live at the end of 2019, bringing faster, more frequent trains to the travelling public years ahead of the completion date.

Four Lines Modernisation (4LM) project

4LM is a project to increase capacity within London Underground and will upgrade the signalling systems of four of the most important railway lines: Circle, District, Hammersmith & City and Metropolitan which between them account for 40 percent of Underground traffic.

Unique features of the project include five complex rail junctions, 113 stations and 191 trains, interfacing the system with four depots and the integration and presentation of existing trains and PA systems with a central control centre.

Ageing infrastructure, in parts up to 150 years old, meant this was a challenging task that needed to be delivered quickly and accurately.

The four lines are among some of the oldest sections of the Underground network, with parts dating back to 1863. Together they make up 40% of the Tube network, with around a million passenger journeys each day.

Some equipment used on these lines is old and needs to be replaced. Tratos is pleased to support the ongoing efforts of TfL in introducing new technology that will reduce journey times and allow us to run more trains – essential to support London’s growing population.

Work to install a new signalling and control system began in summer 2016 and now is almost complete. This will eventually allow the trains to be driven automatically, with a train operator in the cab to open and close the doors. The train operator will be responsible for managing customer information and safety.

About Thales GTS

Thales GTS Ground Transportation Systems supports mainline and urban rail within the UK. Working with customers such as London Underground and National Rail on large infrastructure and civil engineering programmes ranging from telecommunications through to rail signalling and traffic management systems.

Thales GTS is a team of over 6,500 experts, including 4,500 highly skilled engineers, across nine key UK sites. They have unrivalled experience across every major industry we serve – working around the clock to make life better and to keep us safer. 

Thales GTS is a global technology business operating across aerospace, defence, digital security, transport and space.

Each year they invest over £575 million into our UK supply chain, working with over 2,000 companies. 

Thales GTS  is dedicated to research and technology, working with our partners to invest over £130m + in R&D annually.

With a heritage of over 130 years, they understand the importance of developing skills for the future which is why we have over 400 apprentices and graduates across the UK. They are committed to supporting our people, and continuously developing talent, and highly skilled experts.

Operating across 68 countries, Thales Group helps make the world go round. We work with over 80,000 people across the globe every day to keep the public secure, guarding vital infrastructure and protect national security.

From the bottom of the oceans to the depths of space and cyberspace, we help our customers think smarter and act faster – mastering ever greater complexity and every decisive moment along the way.

Tratos is long committed to supporting sustainable transport and the UN Global Goals related to the transport, such as Goal 1 End poverty in all its forms everywhere,  Goal 3: Good Health and Well-being,  and Goal 11: Sustainable Cities and Communities.