Big pike
| Big pike | |
|---|---|
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| Number: | 35 railcars |
| Manufacturer: | Christoph & Unmack , LHB , LOWA , Sachsenwerk |
| Year of construction (s): | 1929-1954 |
| Retirement: | 1973 |
| Length over coupling: | 15,500 mm |
| Height: | 2990 mm |
| Width: | 2150 mm |
| Empty mass: | 21.0 t |
| Top speed: | 70 km / h |
| Hourly output : | 4 × 55 kW = 220 kW |
| Operating mode: | Bidirectional locomotive |
| Seats: | 36 |
| Standing room: | 75 |
The Große Hecht is a tram - railcar type in large-scale construction , which was used in the Dresden tram network. It was presented in September 1930 at the meeting of the Association of German Transport Administrations. With the various technical innovations, a new era in tram construction began with these cars. The more than 15.5 meter long vehicles are strongly tapered at the ends, so that they got their common name after the Hechtwagen on the railroad with a similar layout.
history
After the First World War , individual motorization began in the United States and Europe . In the 1920s, automobiles and buses became serious competition for the tram companies, which usually only had a rather outdated vehicle fleet.
The new development of a tram car with a high travel speed , good driving characteristics, a large capacity , more safety and better driving comfort was necessary.
At the end of the 1920s, the Dresdner Straßenbahn AG, the wagon construction company Christoph & Unmack in Niesky and the Sachsenwerk Licht- und Kraft AG Niedersedlitz developed this new type of vehicle under the direction of Professor Alfred Bockemühl , the then director of the Dresdner Straßenbahn AG.
The development costs of the Hechtwagen were a few thousand Reichsmarks, in contrast to the development costs of over 750,000 US $ for the PCC tram (1932–1936, predecessor of the T4D ). Nevertheless, the test results were very satisfactory.
On December 23, 1929, the first large Hecht railcar (number 1701) was delivered to Dresden . The second car followed on July 6, 1930. These two vehicles were on the express line E15 between Coswig and main railway station extensively tested.
In 1931 Dresdner Straßenbahn AG acquired 22 more large pike ; the railcars from 1703 to 1714 were built by the Christoph & Unmack company in Niesky , while the railcars from 1715 to 1724 were built in the Linke-Hofmann-Busch wagon factory in Bautzen . In 1932 and 1933, another 9 railcars were ordered. For the cars from 1725 to 1729, Christoph & Unmack only supplied the box framework and the Dresdner Straßenbahn AG completed them in their own workshops. The cars 1730 to 1733 were again delivered complete. The electrical equipment came from the Sachsenwerk.
In World War II 8 Hechtwagen were totally destroyed. In order to be able to fully equip tram line 11 with these cars again, VEB Lowa Waggonbau Görlitz manufactured two more Hecht railcars (1726 and 1727). These were delivered in October 1954.
Sidecars of the same shape were not developed. Christoph and Unmack delivered large steel sidecars with a special bogie , an axle base of 3500 mm and a length over coupling of 12,400 mm for operation with the large Hecht wagons .
technical features
The four-axle bogie vehicle is 15,500 mm long ( LüK ), 2150 mm wide and 2990 mm high. The car body tapers to 560 mm at the platforms so that it is possible to encounter oncoming trains safely even in arches. The floor height in the interior of the car is 700 mm with the original, plain-bearing bogies. During the later modernization, the wagons received new bogies with roller-bearing wheel sets. The floor height of these railcars rose to 760 mm. When empty, the vehicle weighs 21 tons and offers a total of 111 passengers (36 seats and 75 standing places).
The semi-automatic control of the tram is a notable advance. To achieve the required high acceleration and speed, the Hechtwagen received four half -voltage motors - that is, two drive motors that are constantly connected in series - with an output of 55 kW each. The core is the electromechanically operated underfloor central drive switch. This device has a separate drive and brake switch and is located under the floor in the middle of the car. The 16-stage drive switch is controlled by push buttons in the driver's cab via an electromagnetic system. A current monitor regulates the switching speed automatically depending on the load. The rotation of the drive roller tensions a return spring which, when the brake pedal is pressed, brings the drive roller back into the zero position. The 16-step brake switch is controlled by a pedal that is connected to the device via a linkage.
The vehicle is equipped with three independent braking systems: the electrical resistance brake as a service brake, four magnetic rail brakes and a parking brake , the latter of which can only be operated manually. The first door is operated by the driver via a chain hoist, the rear doors can be opened and closed by the passengers.
In order to make effective use of the entire vehicle space, the rear driver's cab that is not required can be folded up.
Since the Hechtwagen is designed as a bogie vehicle, the driving characteristics on straight and winding routes are very good. A fully occupied vehicle is permitted for a maximum speed of 70 km / h on level roads. However, it was reported by the drivers that the pike on the overland route 15 to Weinböhla (today's route 4) should have reached speeds of up to 120 km / h. The official record is 98 km / h, measured during test drives on the Königsbrücker Landstrasse. This value is still considered to be the world record for trams.
commitment
The scheduled service of the large pike took place from October 20, 1931 on the lines 11 (Hauptbahnhof - Bühlau ), 15 ( Niedersedlitz - Weinböhla) and partly on the line 25 ( Trachau - Gruna , later Radebeul West - Leuben ).
In the air raids from February to April 1945 , 8 large Hecht wagons were destroyed (1704, 1710, 1716, 1725, 1727, 1728, 1729, 1730). The badly damaged car 1732 was rebuilt in 1951 by VEB Lowa Waggonbau Bautzen. After renumbering in 1952, the vehicle series of the Großer Pechte initially ended with the car number 1725.
The remaining 25 Hecht wagons could no longer cover the vehicle requirements of line 11. Therefore, in 1953, VEB Lowa Waggonbau Görlitz started to build two large pike railcars. In October 1954 these railcars with the numbers 1726 and 1727 were delivered to Dresden.
In the early 1950s, the first Hecht wagons began to show signs of wear. Cracks appeared on the bogie frame, so that new bogies were designed in cooperation with VEB Waggonbau Görlitz . These bogies with welded frames are reinforced at important points and have new suspension. The bogies were installed during the general overhaul (1951–1954), during which the pikes received new interior lighting, a low-voltage system and new seat covers. With the arrival of the Czechoslovak Tatra wagons from 1967, the elegant Hecht wagons were gradually pushed out of regular service. After more than 40 years of service, most of the large Hecht railcars had covered over 3 million kilometers in the Dresden route network.
Today the 1702 car in the Dresden Transport Museum and the 1716 car with the 1314 sidecar are still operational in the Dresden Tram Museum. The coaches 1701, 1710, 1712, 1719, 1720 and 1722 still had the original leather seating until their end.
