Penso British Engineering

Lightweight Composite Rail Door

The Challenge

To manufacture a composite door leaf assembly that looks to build on existing performance by improving reliability and maintenance. To deliver substantial mass savings per door leaf and present a bolt-in window cassette solution. The risk of water ingress must also be reduced.

The Penso approach

Penso started by reverse engineering the current aluminium door. The company then had to generate a CAD model to replace 2D line drawings and a CAE analysis against 92TS technical specifications.

The next step was to manufacture composite sandwich panel test coupons, which successfully passed fire, smoke and toxicity testing to meet both stringent requirements: BS6853 Category 1A and GMRT 2100.

Penso then demonstrated their manufacturing feasibility of a press formed composite door through prototype build, followed by fit and function checks at Transport for London depot.

The final step was to design a test rig to ensure prototypes are compliant with deep tunnel 92TS load cases.

The Results

Penso successfully produced a press formed phenolic pre-preg composite door with an integrated core sandwich panel.

A mass saving of more than 10kg from the current aluminium incumbent door was created with Penso’s design.

The risk of water ingress has been reduced due to a closed cell core structure.


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