SJ T21 facts for kids
Quick facts for kids T21 |
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| Power type | Diesel-electric |
|---|---|
| Builder | Maschinenbau Kiel Svenska Järnvägsverkstäderna |
| Build date | 1955-59 (SJ) 1963 (NBJ) |
| Total production | 60 |
| UIC classification | D |
| Gauge | 1,435 mm (4 ft 8 1⁄2 in) |
| Wheel diameter | 1,255 mm (49.41 in) |
| Length | 11,300 mm (37 ft 7⁄8 in) |
| Locomotive weight | 56.8 tonnes (55.9 long tons; 62.6 short tons) tare weight |
| Transmission | Hydraulic |
| Power output | 590 kW (790 hp) |
| Tractive effort | 170 kN (38,000 lbf) |
The T21 is a special type of train engine. It's a diesel-hydraulic locomotive, which means it uses a diesel engine and a special fluid system to move. These engines were first known as T2. They were used in Sweden by the Swedish State Railways (called SJ) and another company named Nora Bergslags Järnväg (NBJ).
What is the T21 Locomotive?
The T21 was built in the 1950s. A total of 60 of these powerful engines were made. Two companies, Maschinenbau Kiel and Svenska Järnvägsverkstäderna, worked together to build them. The design for the T21 came from a German train engine called the DB Class V65. The T21 was very similar to another engine, the MaK 800D.
Why Was the T21 Important?
The main job of the T21 locomotives was to replace older steam locomotives. Steam trains used to be very common, but diesel engines were more modern and efficient. The T21s were perfect for pulling trains on smaller railway lines, known as branch lines. They helped keep trains moving across Sweden. These engines were used for a long time, all the way up until the 1990s.
Building the T21: A Small Challenge
When the T21s were first ordered, there was a plan to build 56 of them. Ten of these were supposed to be made in Sweden with a special Swedish "hydraulic shift" system. This version was called T3, and later T22. However, this new Swedish system didn't work as well as hoped. Because of this, only four of the T3/T22 engines were actually delivered with that system. The rest were built with the German system. Later, two of the T3/T22 units were even changed to become regular T21s. In 1963, the NBJ company bought four T21 engines for their own use.
