FS Class D.445
Class D.445 diesel locomotives are among the most modern ones of italian Ferrovie dello Stato (FS) railway company. They have been built between 1974 and 1988 in 150 units, divided into three series.
History
Class D.445 represents the natural evolution of the D.443 engine of which has maintained the peculiar reliability and good operativity. At the beginning of the '70s FS, during a plan aimed at the expansion and modernization of current service, designed a new version of an unified diesel engine whom could also resolve in a efficient and rational way the typical carriage heating issues of other engines through the implementation of an high tension electric line (REC, Riscaldamento Elettrico Carrozze) fed by a secondary generator. In fact, previous diesel locomotives weren't provided with such line and forced use of a specific and appositely suited wagon (called Carro Riscaldo), leading to an evident waste of hauled weight. The first series of locomotives, introduced from 1974, were built with curved frontal glasses which would be later replaced by cheaper and sturdier flat ones. In 1979 a second series was ordered, fitted with remote control line and equipment for use with control cars. At the end of the '80s the whole group consisted of 150 unit which allowed the retirement of the then old D.341 and D.342 locomotives.
Description
The locomotive follows the general unified characteristics of other engines about the chassis and mechanical design. The biggest differences are inside the electrical part: the two DC motors (permanently in parallel) are fed by a three-phase AC generator (in place of a DC one) through a Graetz Bridge; an high tension secondary DC generator provides the 3000 V DC for carriage heating. In particular the secondary generator provides a 300 kW output (about 2750 V), able to supply enough power for 7/10 coaches depending on the type of climatising equipment installed.
Diesel engine is produced by FIAT, type A2212 SSF supercharged with 12 “V” cylinders. Displacement is of 95700 cm3 and the available power is of 1560 kW at 1500 rpm. Motors are cooled by radiators, an inter cooling system with forced circulation of cooling fluid and by two vertical fans driven by an hydraulic motor, Behr system. The three phase generator is controlled by an electronic PWM control unit which is commanded by a 13 step regulator.
Technical details
1st series units originally had curved frontal glasses, replaced in the '80s by flat glasses employed since construction on 2nd and 3rd series units. The locomotives have a B'B' wheel arrangement and their maximum allowed speed is 130 km/h. Like most of the FS stock, even D.445 have received an XMPR color scheme (white, green, blue).
1st series
35 units numbered from 1001 and 1035 in green-isabella livery. Equipped with three headlights, weren't provided with remote command system, applied starting from october 1996. They still had curved frontal glasses.
2nd series
20 units (1036-1055) in push-pull livery (Navetta livery, orange/purple) and still with three headlights. The main difference between 1st and 2nd series units was the presence of remote control equipment for use with control cars.
3rd series
3rd series units amount to 95 units numbered 1056 / 1150, in push-pull livery as 2nd series' units but with five lights on each cabin (three headlights and two red tail lights). Like 2nd series, they can be controlled by apposite carriage.
References
- Vittorio Cervigni (1984). Locomotive diesel D.445, from iTreni oggi 41.
- Ferrovie dello Stato. D.445 technical documentation.