FS Class E626

Infobox Locomotive
name=FS class E625/E626
electricsystem=3,000 V DC
tractionmotors=DC series
powertype=Electric


caption=An E626 in the National Museum of Transportation at La Spezia
builddate=1927-1939
builder=
weight=84.5/97 tons
uicclass=Bo-Bo-Bo
firstrundate=1928
disposition=Decommissioned
numinclass=448 in three series [Plus a prototype series]
wheeldiameter=1.250 m
poweroutput=1,850 kW
wheelbase=
tractiveeffort=105 kN
topspeed=50 km/h (E625)
95 km/h (E626)
length=14.950 m
width=
height=
transmission=21/76 (E625)and 24/73 (E626) gear ratios
railroad=FS Trenitalia
The FS E625 and E626 are two classes of Italian railways electric locomotives. They were introduced in the course of the 1920s and remained in service until the 1990s. The E626 was the first locomotive fed by 3,000 V DC lines in Italy.

History

The E626 class is the result of a requirement issued in 1926 by the Ferrovie dello Stato (FS, Italian Railways) for a new locomotive to be used under the new 3,000 V DC line being built between Foggia and Benevento [The previous electrified lines of Italy used three-phase AC current at 16.7 Hz. The 3,000 V is currently the standard system in service, apart some High Speed lines fed at 25 kV AC.] . The design was carried out by the team of Giuseppe Bianchi, the "founder" of modern Italian railroads, at the FS Traction and Material Service in Florence. The requirement specified the locomotive should have 6 traction axles, to improve adhesion in steep lines.

The E626 series was built in 448 units and three series, each with only slight electro-mechanic differences: unadvanced but reliable, it subsequently constituted the mainstay of the new FS lines at 3,000 V DC, which gradually spread to the whole peninsula. The firsts tests occurred on the Foggia-Benevento line in the September 1927, using three prototypes built at Savigliano, with the electric part provided by the Metropolitan-Vickers of Manchester. The first 14 prototypes (8 E625 with shorter gear ratio, for cargo services, and 6 E626) proved powerful and reliable, and entered service the following year. The only teething problem encountered was with the six 32R motors mounting on the axles, hanging laterally over transverse beams, a system devised to avoid the complicate side rods of the contemporary steam and three-phase locomotives: after a series of breakdowns, it was decided to limit the speed to 95 km/h. Traction control was provided by three different configurations of the motors' coupling (series, series-parallel, parallel) through banks of resistor-based rheostats. The transmission was rather noisy, but at the time the crew's comfort was not an important issue. The carbody was in a single steel piece, mounting on an articulated chassis. The large bonnets at the front limited the visibility of the rails, and were reduced in size from the 3rd series.

In 1930 the mass production was started, with a first series of 85 units. In the meantime the E625 were re-converted to E626. In 1934-1938 a record number of 308 units was built, while in 1939 the last series, with short gear ratio, was shipped (they were later standardized). The new E636 of the 1940s initially shared the motors and part of the electro-mechanic devices wit the E626.After the destruction of the World War II, in 1946 an updating and repairing program was launched, while other units remained in the countries previously occupied by Italy. 17 locomotives were ceded to the Yugoslavian Railways (Class E361) and, in 1958, 4 were given to Czechoslovakia (Class E666). Now inadequate to the passenger role, the E626 were transferred to the cargo service, apart several commuter trains in some areas of Italy.

Starting from the 1970s, 14 units were sold to private railways, while the aging E626 still in service with FS (also after complains of trade unions against harsh working conditions of the crew) were increasingly replaced by more modern classes, and demolished. The last unit to be decommissioned was the E626.194, which was used for rescue trains, in 1999.

7 units survive today in museums, while 11 refurbished locomotives are used for historical trains.

Footnotes