GB A 3/5 931-938
| GB A 3/5 | |
|---|---|
 |
|
| Numbering: | 931-938 |
| Number: | 8th |
| Manufacturer: | Maffei / SLM |
| Year of construction (s): | 1908 |
| Retirement: | 1925 |
| Type : | 2'C h4v |
| Gauge : | 1435 mm ( standard gauge ) |
| Length over buffers: | 17460 mm |
| Fixed wheelbase: | 3900 mm |
| Total wheelbase: | 8635 mm |
| Empty mass: | 90.2 t |
| Service mass: | 118.3 t |
| Friction mass: | 49.5 t |
| Wheel set mass : | up to 16.4 t |
| Top speed: | 90 km / h |
| Indexed performance : | 1660 hp |
| Driving wheel diameter: | 1610 mm |
| Number of cylinders: | 4th |
| HD cylinder diameter: | 395 mm |
| LP cylinder diameter: | 635 mm |
| Piston stroke: | 640 mm |
| Boiler overpressure: | 15 atm. |
| Tender: | 3-axis |
| Water supply: | 17 m³ |
| Fuel supply: | 5 t |
| Brake: | Double Westinghouse brake |
In 1908, the Gotthard Railway Company ( GB ) still procured 8 type A 3/5 steam locomotives with a tender . They were given the future SBB numbers 931–938 ex works. The purchase price is given as 146,000 Swiss francs.
background
The locomotives were actually a reorder of the first series of the A 3/5 , but had a superheater since delivery. They were also based on the C 4/5 just delivered by Maffei . This company was also responsible for the design and plans. As a result of the desired delivery before nationalization, four locomotives were built at SLM according to Maffei's plans .
Technically, these locomotives and the A 3/5, which SLM supplied to SBB from 1907, are similar.
Technical
In terms of heating surface and thus also in terms of steam output, the boiler corresponded to the C 4/5. But it was smaller in diameter, but longer. The fire box was quite long at 3120 mm, but narrow due to the large wheels and had a tilting grate for purification. This gave it a smaller grate area than the C 4/5. The center of the boiler was 2800 mm above the top edge of the rail. He initially carried two steam domes . The clench-type superheater (steam dryer) was housed in the front, the steam collector was in the rear. The front steam dome was removed when the Schmidt superheater was retrofitted (1913–1915) instead of the clench. At the same time, the front pipe wall was set back by 600 mm. The boiler now had a new pipe length of 4200 mm and only 198 m³ content. During the conversion, the regulator head was also moved from the front to the rear steam dome.
The bar frame of the locomotive, designed as an inner frame, was 100 mm thick. The coupling axles were supported by 6 longitudinal springs mounted under the bearings. There were compensating levers between axes 2 and 3 . The bogie had a low sheet metal frame and the axles were suspended with 4 leaf springs above the axle bearings. The axle pressure was high, in particular the bogie was loaded with 30 tons, which resulted in a running axle axle pressure of 15 tons. This load lay on two lateral sliding plates, while the guide was taken over by a cylindrical pivot in a spherical sleeve. The bogie could be moved 38 mm on both sides and was centered in the middle with a double leaf spring. In addition, the wheel flange on the central drive axle was turned 5 mm thinner.
The high pressure cylinders were inside and drove the double-cranked first drive axle. The low-pressure cylinders also grabbed the first drive axle from the outside. The inside and outside propulsion units were offset by 180 ° on one side, the two sides by 90 ° to each other. This ensured a very good mass balance. The cylinder axis was inclined at a ratio of 1:18. Each pair of cylinders consisted of a common casting, in which the slide clamps, tubular housing and boiler saddle were also integrated. The outer piston rods were led through to the front, the inner ones not.
The control according to Walschaert was external and operated the three-part piston valve, which was used jointly for high and low pressure, by means of a transverse shaft. This had an inner edge inflow for the high pressure cylinder and an outer edge inflow for the low pressure cylinder. This had short steam paths and low heat losses as an advantage, but had to be bought with relatively large piston valves, which repeatedly led to damage to the entire control system during operation due to the large mass to be moved. There was a flow device for the low-pressure cylinders as a starting aid as well as Ricour suction valves on the high-pressure cylinders. The locomotive did not have a counter pressure brake .
Because of the many tunnels, the locomotive had a smoke-reducing device, a speedometer of the type Klose and a steam heater for the train.
The drive arrangement with a common drive axis according to the Borries system , like the cylinder mass and control parts, corresponded to the C 4/5. This meant that at least some of the spare parts could be used for both machine types. The sandpit was placed on the kettle. The Leach system sand spreading device could be operated both manually and with compressed air.
The three-axle tender was the same as that of the C 4/5. It was a tightly built type with an outer frame and outer suspension springs without compensating levers. The water box was guided around and under the coal box in a horseshoe shape. The tender had a twelve-block spindle brake , on which the Westinghouse brake also worked. The double Westinghouse brake acted on all coupling wheels and the four-block bogie brake on one side. The air tank was installed transversely in front of the fire box between the 1st and 2nd drive axis.
The pulling force was given as 10,000 kilopond , the power as 1660 hp. This made it possible to pull 150 tons on the 27 ‰ slope. The trailer load was thus somewhat greater than that of the A 3/5 of the first series.
| number |
Factory number |
Construction year | Manufacturer | Clench type superheater |
Schmidt type superheater |
Discarded |
|---|---|---|---|---|---|---|
| 931 | 2727 | 1908 | Maffei | 1908 | 1914 | 1925 |
| 932 | 2728 | 1908 | Maffei | 1908 | 1913 | 1925 |
| 933 | 2729 | 1908 | Maffei | 1908 | 1913 | 1925 |
| 934 | 2730 | 1908 | Maffei | 1908 | 1913 | 1925 |
| 935 | 1892 | 1908 | SLM | 1908 | 1914 | 1925 |
| 936 | 1893 | 1908 | SLM | 1908 | 1915 | 1925 |
| 937 | 1894 | 1908 | SLM | 1908 | 1914 | 1925 |
| 938 | 1895 | 1908 | SLM | 1908 | 1915 | 1925 |
- ↑ The locomotives were given numbers according to the SBB scheme from the start
Operational
The locomotives were always assigned to the Bellinzona workshop and thus to SBB District V. All locomotives were scrapped in 1925 and then scrapped.
Sources / literature
- Alfred Moser: The steam operation of the Swiss railways 1847-1966 . 4th updated edition, Birkhäuser, Stuttgart 1967. S. 159ff.