Deutsche Bahn

Differential pressure measurements remedy door malfunctions

(München, April 2020) Train crews consistently reported door malfunctions on the first-class Intercity 2 double-decker coaches (Do2010). Adjustments and tests in the maintenance depots did not reveal any faults on the doors though.

The vehicle specialists at DB Fernverkehr focused on the pressure conditions in the passenger area as one possible cause of these door malfunctions. To determine whether unacceptable pressure differences built up during operation which prevented the doors from operating properly, DB Fernverkehr contracted DB Systemtechnik to analyse the faults.

DB Systemtechnik carried out differential pressure measurements in the passenger area using measuring equipment installed in the vehicle. The measurements were conducted at rest and while moving together with the vehicle manufacturer. They demonstrated that increased internal pressure could build up in certain operating states of the HVAC system and in combination with the non-return valve in the exhaust-air opening.

Based on this analysis, the vehicle specialists from DB Fernverkehr and the vehicle manufacturer managed to identify this high internal pressure as the cause of the door malfunctions. The solution adopted together with the manufacturer remedied the door malfunctions once and for all.