Helsinki City Transport to launch bidding contest to prevent repeating previous mistakes with low-carriage trams
Ability of trams to handle tight corners crucial
With the acquisition of new trams on the horizon, Helsinki City Transport (HKL) wants to avoid the problems that it encountered with the low-carriage trams provided by the German manufacturer Bombardier. The Bombardier Variotram trams have been fitted with fixed bogeys.
HKL is currently assessing nine different tram manufacturers’ visions of what kind of next-generation trams would suit Helsinki.
Many of the proposals suggest that Helsinki acquire trams with pivoting bogeys, possibly accompanied by a low-carriage structure.
The bogey solution is one of the essential questions related to the upcoming procurement of trams.
Variotram’s fixed bogeys have proved extremely problematic in Helsinki’s demanding tram network. Fixed bogeys are unable to conform sufficiently to heavy trams’ movements in tight corners. The wheels and the tram chassis are being strained, while the rails underneath wear out.
Having learned from costly past mistakes, HKL has now organised a kind of pre-competition, in which different manufacturers’ visions are sought for a tram type that would be best applicable for Helsinki’s situation.
“In our understanding a maximally pivoting bogey under the tram would be a good solution for Helsinki. An overly rigid bogey causes more problems”, says development chief Ollipekka Heikkilä from the HKL Tram Unit.
During the first part of the next decade Helsinki will acquire around 40 new trams.
The tram series will answer to the city’s growing need for public transportation brought on for example by the introduction of the new city district of Jätkänsaari.
The actual bidding contest is likely to be launched in June.
Heikkilä is reluctant to start commenting directly on the pre-competition proposals presented so far by various tram manufacturers.
“We have received several offers with varying technical solutions to the bogey issue. But generally it seems that tram manufacturers are heading back to the more traditional approaches”, Heikkilä answers diplomatically.
The pivoting bogeys’ roots are in traditional technical solutions, but fitting them to low-carriage structures has so far proved a challenge. In the latest tram types, however, the two have been successfully amalgamated.
For example Skoda has announced that it will respond to the challenge presented by HKL and offer its latest tram type to the contest.
From Helsinki’s point of view the matter is important.
The official policy postulates, for example, that the city’s public transportation system is easily accessible by the elderly and the disabled.
According to Heikkilä, many of the manufacturers have used different types of computer applications to simulate how well their particular designs would suit Helsinki’s demanding tram network.
Previously in HS International Edition:
Helsinki City Transport testing Croatian low-carriage tram (19.12.2007)
Helsinki City Transport seeks leaseback deal for troubled Bombardier trams (20.4.2007)
Helsinki City Transport (HKL)