SJ Da

The Swedish series There is an electric locomotive for universal use, which was built in 1953 for the Swedish State Railways Statens Järnvägar.

History

The Swedish State Railways has electrified 1940-1960 many routes over the years. On the basis of this results in demand for electric locomotives another 100 locomotives were ordered with three driving axles at ASEA. In 1960, the last of a total of 93 locomotives was completed since. From 1990, it began with the withdrawal and scrapping of Da.

As a universal locomotives were the As found in Sweden. It was used in passenger and freight service. Due to the multiple unit control even heavy trains could be done with the rather small locomotives.

From Since the two-part Dm and the three-part Dm3 for Erzverkehr in northern Sweden have been developed. The latter are still in use today.

Technology

The Da based on the reliable and proven D series, which was developed in the 1940s for the SJ. Sweden had a long tradition of bar- driven electric locomotives and doubted the suitability of the operating Einzelachsantriebes so that a more rods electric locomotive has been commissioned, although this concept was at that time already considered by many railways obsolete.

Compared to their older sisters in the D series, many changes have been made, so that the locomotive with its predecessor series, only the wheel arrangement had together. Drive axles, bearings and traction motors were new designs. The cooling air inlet was moved from the side wall to the roof. The cabs were windows with rubber seal, which externally are the locomotive against the D - series a more modern look. Next, the locomotives were equipped for multiple operation, so that up to three locomotives from a cab from could be served.

The locomotives were initially delivered with spoked wheels. The locomotives had by the imbalance of Stangenatriebes poor running performance, which has made ​​itself felt especially in the fast passenger. The forces between wheel and rail were so high that repeatedly occurred Radsternbrüche. The problem has been studied scientifically by technicians of the SJ, was also being the first to develop a viable method for measuring the forces between wheel and rail.

In the 1970s, all because locomotives were fitted with resilient wheels. This substantially better running characteristics have been achieved. In experiments, a locomotive even reached 160 km / h

Despite the expansion, the locomotive retained its good qualities: With a service weight of 75 tons and the pinion drive, it is virtually impossible to bring the loco to spin. This could even be drawn with the rather low power of 1840 kW heavy trains.

Some of the locomotives were later given the " Nordland cabs " with very good thermal insulation.

Drive

The Da is powered by two single-phase series motors which are supplied via a transformer tap changers. The motors operate via a gear on the jackshaft between the three driving axles. About Kuppelstangen the driving axles are connected to the driven jackshaft. The first and last axle of the locomotive are running axles. They are used to reduce the axle load and better tracking. At one barrel axis and donors for the speedometer and the anti-skid system is connected.

Remaining machines

Since following locomotives are still in use or preserved in museums:

• Since 790 (the first locomotive of the series) is the Swedish Transport Museum
• Since 804, 887 and 903 go in the service of the Swedish private railway Tågfrakt AB. They have a blue - silver finish.
• Since 889 is serving the MTAB in Kiruna on the road for use with the emergency train.
• Since 941 (now known as "Da 15") goes for the Swedish private railway Tågkompaniet and is often used in tourist traffic.