GB Ed 2x3 / 3
| GB Ed 2x3 / 3 | |
|---|---|
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| Numbering: | GB 151, SBB 7699 |
| Number: | 1 |
| Manufacturer: | Maffei |
| Year of construction (s): | 1890 |
| Retirement: | 1917 (sale) |
| Axis formula : | C + C |
| Type : | Composite |
| Gauge : | 1435 mm ( standard gauge ) |
| Length over buffers: | 13776 mm |
| Empty mass: | 69.4 t |
| Service mass: | 87.2 t |
| Friction mass: | 87.2 t |
| Wheel set mass : | 14.5 t |
| Top speed: | 45 km / h |
| Driving wheel diameter: | 1230 mm |
| Control type : | Walschaert |
| Number of cylinders: | 4th |
| Piston stroke: | 640 mm |
| Boiler overpressure: | 12 atm. |
| Number of heating pipes: | 190 |
| Heating pipe length: | 4500 mm |
| Grate area: | 2.2 m² |
| Radiant heating surface: | 9.3 m² |
| Evaporation heating surface: | 154.3 m² |
| Water supply: | 7 m³ |
| Fuel supply: | 4.3 t |
In 1890, the Gotthard Railway Company ( GB ) procured a Mallet- type tender steam locomotive , which was designated Ed 2x3 / 3 and number 151. The machine was built by Maffei in Munich and was advertised as the most powerful locomotive in Europe upon delivery. The purchase price was 90,200 Swiss Francs.
history
Due to the long and steep ramp routes, almost all trains on the Gotthard required a leader locomotive, if not two, and pushing was more common than the exception. So it is not surprising that the company looked around for a suitable and powerful locomotive for pre-tensioning freight trains on the mountain route and, in 1890, was the first railway company in Switzerland to acquire a locomotive with the Mallet duplex system. The locomotive was designed as a tank locomotive and all axles were powered. However, the locomotive had a boiler that was too small for its performance, so that it could only achieve its maximum performance for a short time. On the long inclines, however, permanent maximum performance would have been required. Had it not been built as a tank locomotive, a larger and more powerful boiler would have been possible. As it was, the maximum permissible axle pressure of 14.5 tons had actually already been exceeded. In addition to the inadequate continuous output, the locomotive was also prone to failure. This was due to the mallet drive and its many moving parts. Another problem was that the pulling force on the towing hook was greater than was permitted on a number of old foreign freight wagons. The locomotive was therefore usually not allowed to use its power at all. So there were various reasons to refrain from re-ordering and to continue to procure four-fold coupled locomotives with which one could gain good experience ( GB D 4/4 ). That is why the locomotive remained a one-off. When the GB was taken over by SBB, the machine was given the number 7699. In 1917 it was sold to Brussels.
technical features
The boiler was fixed at the back and supported on the front frame by means of two sliding jaws mounted in oil on movable supports. The lower edge of the boiler was 2320 mm above the upper edge of the rail. The boiler had a large steam dome. The safety valves were under a large hood. There were also two sand domes. A Langer smoke burner was installed to reduce smoke pollution in the tunnels.
The engine had a fixed and a movable engine frame , both of which possessed an inner frame. The fixed drive frame was under the fire box (so it was at the rear). The fixed wheelbase in both bogies was 2700 mm. There was a leaf spring under each axle bearing and connected to one another with compensating levers: laterally with one another with longitudinal levers, and the spring ends of the end axles on the head side of the drive frame with transverse double levers.
The high pressure machine acted on the rear engine frame. The low-pressure machine was attached to the front, movable drive frame. The low-pressure steam supply (3–4 atm.) Was carried out via a ball joint that was located in the pivot point of the frame. The exhaust steam was led to the blowpipe via a movable exhaust pipe. For starting up under load on inclines, a device was available that allowed live steam to be fed into the low-pressure cylinder, although the exhaust steam from the high-pressure machine was not used.
All four cylinders were slightly inclined and had trick channel flat slide valves with external channel inflows. Both the high and low pressure machines acted on the third drive axle, which was connected to the other two axles with coupling rods. Only in the front frame were the piston rods passed to the front.
The first and third axles of each frame were braked on one side, so they had one brake block per wheel. This brake was designed as a Hardy vacuum brake on delivery; it was replaced by a vapor brake in 1894. The handbrake, which was designed as a spindle brake, acted on the brakes of the rear frame. The locomotive never had a Westinghouse brake, and no counter-pressure brake was installed.
Operational
The locomotive was always assigned to the Bellinzona workshop for major maintenance.
Literature / sources
- Alfred Moser: The steam operation of the Swiss railways 1847-2006 . 7th updated and supplemented edition, Swiss Association of Railway Amateurs (SVEA), Bühler Druck, Zurich 2006. ISBN 978-3-033-00948-6 (chapter "Corrections and new findings", page X, to page 399)
- Adolf Brunner: Europe's largest locomotive . In: The Gazebo . 1891, p. 198 f . ( Full text [ Wikisource ]).