B900920 is a 25 ton capacity bogie well trolley wagon built to BR Diagram No.2/741 at BR's Swindon Works to a 1958 order. Given
the telegraphic code Weltrol WP, indicating that it was built for British Railways Western Region, it was constructed as part of lot 3102
which comprised Nos.B900912–922.
A further 14 to the same design, lot 3192, were constructed in 1960, bringing the total number of vehicles to this diagram to 25.
They were built with a through vacuum brake pipe in order that they could run within fitted trains.
These wagons were designed to carry very heavy loads, such as transformers or other machinery, which would usually have been supported
on the side girders.
With the decline in the British heavy engineering industry and the improvement in heavy road haulage, the vehicle became surplus to
traffic requirements. It was placed into departmental service with Traffic Dept., being one of five converted at BR's Springburn
workshops into a loading ramp wagon for BR's Motorail car-carrying service and gaining the number TDB96450. Its purpose was to allow
cars to enter the car-carrying vehicles from the platform at which they were standing.
Cars accessed the ramp wagon via the flat section mounted over the well, using drop-flap sections to bridge the gap between vehicle
and platform. The fixed ramp was at one end of the wagon, and the whole was covered by a lightweight roof.
The wagon was acquired for the Bluebell Railway, where the loading ramp was removed. The vehicle has subsequently been in constant use as
a locomotive boiler carrier.