As part of The New Tube for London project, trains, stations and tracks of the London Underground Network are being modernised to increase each line’s capacity and passenger comfort.

The New Tube has been implemented on the Piccadilly line, with the Bakerloo, Central and Waterloo & City lines undergoing consecutive upgrades. The full replacement of some trains, new signalling and other upgrades to the Piccadilly, Central, Waterloo & City and Bakerloo lines will follow. This would not only complete the modernisation of the Underground lines, but create employment and trade opportunities in the UK, as around 50% of the trains will be assembled in a new factory in Yorkshire.

Despite the lack of resignalling, the purchase of new trains will still increase the capacity of the Piccadilly line, with 27 trains per hour at peak times by 2027. Trains will enter service with a train operator, but resignalling of the line could allow for driverless operation in future.

The 250 new Tube trains will be fully air conditioned with more spacious carriages and wider doors, to provide more comfortable journeys for passengers. Their energy consumption will be 20% lower than existing trains due to regenerative brakes, LED lighting and lighter construction.

As the new trains are built, as well as being BS6853 Cat 1A approved for use in rail vehicles, all materials must be LUL (London Underground Library) approved for use on the London Underground Tube lines. The LUL 1-085 – Fire Safety Performance of Materials standard specifies the essential requirements for materials used in London Underground locations. This standard applies not only to stations and running tunnels, but also to all passenger and engineering trains.

Materials must be specified for:

• Flammability (include the risk of explosion)
• Smoke emissions
• Toxic fume emissions

That’s why Armacell UK’s distributor of Armaflex Rail SD insulation materials within the UK, CB Frost, was specified on the project. CB Frost has had a strong partnership with Armacell UK since 2018. Supplying Armacell’s Rail technology to be used on The New Tube, CB Frost guaranteed that the strict material specifications of project would be met.

In rolling stock, heating ventilation and air - conditioning (HVAC) equipment is the second largest energy consumer after the traction. Insulating this mechanical equipment with Armacell’s closed-cell and highly flexible ArmaFlex Rail products is one of the simplest and most efficient measures to save energy in railway vehicles.

Armaflex® Rail SD & SD-C sponge is the world’s first flexible closed cell insulation material to meet EN45545-2 fire protection requirements. It is one of the leading closed cell thermal insulations available to the railway industry worldwide and comes complete with a built-in vapour barrier reducing the risk of corrosion under insulation (CUI). Armaflex® Rail SD & SD-C foam has been developed to produce extremely low smoke density and reduce the risk of mould and mildew contributing to an improved indoor air quality. Armaflex® Rail sponge comes in two grades: standard SD or SD-C which features a silver metallic coating.

The trains are expected to enter service on the Piccadilly line in 2025 with improvements to service levels to follow in 2027.

See a video about the project: https://youtu.be/Z3Q0FZUKHkY

For more information on Armaflex® products or cellular silicone materials for the rail industry, call CB Frost’s team on +44 (0)121 773 8494 or contact Daniel, Brock Business Development Manager, on email: daniel.brock@cbfrost-rubber.com.

If you would like to find out more about the full range of products they offer for the transportation industry, please visit or call their Customer Service Team on +44 (0) 161 287 7100 to order some information or product samples today.