Tram with a direct articulation

Three section tram with the wheels centred.

A tram with a direct articulation is a type of articulated tram. In this type, the car sections have their wheels in the middle. These car sections are directly linked by a pivoting joint (articulation) enclosed by protective bellows inside and outside and a cover plate on the floor. The sections may be controlled by rods and/or hydraulics. The first successful series was built and put into service in Bremen, which is why the concept is known as the Bremen type in Germany. A more common name in Germany is Kurzgelenkwagen.

History

An early attempt to link sections directly resulted in the RETM tram 501/502. This tram with four fixed axles only ran from 1924 to 1928. Due to its poor running characteristics, initially few models were replicated: a single test tram, such as the Ce160/162, was put on the rails in Bern, Switzerland. In Munich four four-axle trams were coupled in pairs in 1936/37, resulting in two eight-axle trams.

Construction

Bremen Type

Main article: GT4 (Bremen)

A prototype of this concept was built in Bremen in 1959. These following series were locally called GT4, chronologically supplemented by a letter from the alphabet: GT4a through GT4f. Series a, b, and c were built in the 1960s, while series d, e, and f were a further development and were built in the 1970s. These four-axle trams have better running characteristics than the pre-war articulated four-axle trams in other cities, because they are equipped with bogies instead of a fixed truck.

DT8 in Stuttgart

Progression

In 1965, a prototype for the Munich tram was built. In the following years, series of trams were delivered (P2/3 motor cars and P2/3 trailers). The Czech tram type Tatra KT4 was also constructed according to this concept, and in total 1,767 were built. The two car sections of the later generations of the DT8 tram for the Stuttgart Stadtbahn are also directly connected.

Low-floor trams

The city of Bremen also had the first low-floor version in 1990. Munich and many other (primarily German) cities followed in later years. As of 2025, this concept is still in use, although no longer by the original manufacturer, but by companies such as Siemens (Avenio), Solaris, Astra and CRRC.

Gallery

• 
  Two-section tram in Bremen
• 
  Two-section tram in Galati
• 
  Three-section tram in Frankfurt
• 
  Four-section tram in The Hague
• 
  Six-section tram in Budapest

See also

• Articulated tram