Entered service 1969–2016 Number built 50 | Constructed 1968–1973 Refurbishment 1994-2000 Fleet numbers 6001+6201 – 6050+6250 | |
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The electric multiple unit Sm1 is a class of commuter train equipment that was in active use by the VR Group (Finnish Railways) from 1969–2016. Fifty Sm1 units were built between years 1968 and 1973 at Valmet airplane factory in Tampere. It was put into use on the first electrified Finnish railway line between Helsinki and Kirkkonummi on January 26, 1969 with five units in operation. All Sm1 units were thoroughly renovated in the 1990s. Commercial service ended in April 2016.
Technical information
Each Sm1 unit consists of two cars, Sm1 actually being the class of the motored carriage in the two-car unit. The other car is called a driving trailer and its class is Eio . The two-car unit has 191 seats combined, including fourteen foldable seats. There is a driver's cabin at either end of the unit, which enables the train to be driven in both directions without turning it around. This is a major advantage compared to locomotive-pulled trains in commuter traffic.
Six Sm1 units can be coupled together, but trains in commercial traffic are limited to five units, because of the length of the station platforms. It is possible to see six Sm1 units coupled together during switching duties between the Ilmala depot and the Helsinki railway station. The units use Scharfenberg couplers.
The maximum speed of the unit is 120 km/h (75 mph). They are numbered between 6001/6201 and 6050/6250 (Sm1 car / Eio driving trailer). The electric systems were developed and built by Strömberg at their plant in Pitäjänmäki, Helsinki.
The Sm1 is technically very similar to the newer Class Sm2 EMU, although there are also some differences, such as the Sm1 having steel spring suspension and strengthening creases on the sides.