Tram Gearbox Rebuild Complete
Both Roosevelt Island Trams are operating at full capacity after a recent period of the North Tram cabin running on a reduced or 50 percent passenger weight-load capacity, RIOC said Monday.
On August 31, the North Tram gearbox began to produce intermittent noises, which were localized to the intermediate gear inside of the box. Out of concern of the potential risk of damage to the equipment, the component was removed from service.
Each Tram operates using two motors and two gearboxes; if one is removed, operators must also remove about 50 percent of the load, RIOC said.
Because the Tram was designed with multiple redundancies, engineers from Leitner-Pomo – the operations company that RIOC contracts to run the Tram – were able to remove this gearbox and continue to operate using the remaining motor/gearbox combination at the reduced capacity.
The gearbox is manufactured by Kissling AG, a Swedish company; and a decision was made to bring in the engineering experts from the manufacturer to handle the repair. A Kissling crew traveled to Roosevelt Island from Bachenbülach, Switzerland, inspected and determined the location of the noise to be coming from a keyway on the intermediate gear shaft. That part was replaced by a shaft from the spare gearbox, which Leitner-Pomo had here on location. The spare gearbox is now slated to be rebuilt.
The Tram returned to full-load service last Monday, September 17.
RIOC apologizes for the inconvenience and thanks residents, RI workers, students and visitors that ride the Tram regularly for their patience.