Project "Sokol"
The interiors of open-type passenger coaches; class: 1, 2 and bar car; during the overhaul of the B84 coaches (series 1974 and 2974).


The overhaul is carried out by ”Train Car Factory – Intercom“ JSC, Dryanovo, Bulgaria, in partnership with the IBT-group. The Train Car Factory, relying on the wide range of design and production capacities of the MDC (Ukrainian manufacturer), as well as the logistics capabilities of the IBT GmbH (German head office), successfully completed the following tasks within the scheduled time frame and within the budget:
● Selection of car layouts after many iterations to harmonize with EU safety regulations. Many requirements seemed incompatible due to contradictions between them. For example: On the one hand, the following parameters are set or objectively exist: the required passenger capacity, the cutting of the interior volume by vertical air ducts, the original body structure for a compartment layout. And on the other hand, such norms are obligatory: seat space, aisle width, number of emergency exits, height and ways for luggage placement, air speed, etc. The applied methods for creating and managing mathematical models and calculation schemes made it possible to quickly and repeatedly count and analyze them. Such flexibility allowed numerous recalculations and the final design that ideally satisfies all requirements.
● The project teams in Bulgaria and as well in Ukraine, despite the remoteness of the project offices and language barriers, showed well-coordinated parallel work and effective information exchange. This was achieved through the implementation of innovative methods for information accounting and storage with online management of changes.
● The ultra-precise synchronization between the interiors production in Ukraine and the car-body refurbishment in Bulgaria was achieved thanks to the same innovations in the information handling.
● The design features of the car did not allow the use of any existing proposals for luggage racks and passenger tables. Therefore, an R&D complex was deployed, including strength calculations and verification tests. As a result, the car was equipped with an individual proven design of shelves with a unique design.
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● The original air supply and exhaust system was designed for a compartment layout and did not include HVAC. Air units were kept under car-frame to keep existing approved weight allocation and other agreed parameters of the B84 car. The careful air flow calculations made it possible to create a completely new air distribution system, which was organically mated with the interior ceiling and sidewalls.
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● The initially tight production schedule was even ahead of schedule thanks to modular solutions that provided pre-assembled components such as toilet module, ceiling units, luggage racks, etc.
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