UK: Total has replaced the fleet of wagons which carry bitumen from its refinery in Immingham to its processing and distribution plant in Preston with a more efficient design developed in conjunction with leasing firm VTG Rail UK.

The 30 new wagons eliminate the need for staff to access the tops of the wagons, and they have thicker insulation to reduce heat loss during transport.

Bitumen needs to be heated to 180°C in order to flow easily, and the wagons are heated using a bespoke system of external heating coils rather than traditional internal heating. This makes it easier to clean the interior, with no risk of a steam leak into hot bitumen.

A vacuum relief valve is needed to prevent the creation of a vacuum which could result in the tank imploding as a wagon is emptied. To eliminate the risk of this valve becoming jammed by solidified bitumen there is a positive vent valve fitted to the top of the tank, mechanically linked to the foot valve and fitted with an indicator flag visible from ground level.

The Axiom TF25 bogies require less maintenance and are lighter than previous models, increasing the payload by a tonne to 74 tonnes as well as cutting track access charges.

Detailed design of the wagons was carried out by Lloyds Register Rail, with Clayton Commercials manufacturing the tanks and frames and Axiom undertaking assembly.