Swiss Central Railway Ed 2x2/2
In the last decade of the nineteenth century, the SCB needed more powerful freight locomotives. Since they had to be eight-coupled, but had to run through tight curves like those on the Hauenstein line, they were to be Mallets. The order for the new Ed 2x2/2 was placed with Maffei, which also had delivered the Ed 2x3/3 for the Gotthard Railway. So this was inspired by the Gotthard locomotive, but reduced in size to two two-axle groups. The first six were delivered in 1891 and two years later, ten more followed which were lighter, but had larger supplies of water and coal.
As with the Ed 2x3/3, it turned out that their boilers were too small. So the next Mallets delivered to the SCB by the SLM were tender locomotives of the type D 2x2/2, which had a larger boiler. Later the SBB rebuilt two Ed 2x2/2 with new boilers. Today only number 196 is still existing. It was withdrawn in 1938 and after it had resided in the Swiss Museum of Transport between 1959 and 1974, it is operational again since 1992 with the Oensingen Balsthal Railway.
Technical data
General
| Property | 181-186 | 187-196 |
|---|---|---|
| Built | 1891 | 1893 |
| Manufacturers | Maffei | |
| Wheel arrangement | 0-4-4-0T (Four Coupled Mallet) | |
| Gauge | 1,435 mm (Standard gauge) | |
Dimensions and weights
| Property | 181-186 | 187-196 |
|---|---|---|
| Length | 11.52 m | 10.40 m |
| Empty mass | 48.6 t | 44.4 t |
| Service mass | 60.4 t | 58.8 t |
| Adhesion mass | 60.4 t | 58.8 t |
| Rigid wheelbase | 1.90 m | |
| Water capacity | 5,000 l | 7,200 l |
| Fuel capacity | 2 t (coal) | 3.3 t (coal) |
Boiler
| Property | 181-186 | 187-196 |
|---|---|---|
| Grate area | 1.8 m² | 1.7 m² |
| Firebox surface | 7.8 m² | 7.3 m² |
| Tube heating surface | 113 m² | 105.2 m² |
| Evaporative heating surface | 120.8 m² | 112.5 m² |
| Total heating surface | 120.8 m² | 112.5 m² |
Power plant
| Property | 181-186 | 187-196 |
|---|---|---|
| Driver diameter | 1,280 mm | 1,200 mm |
| Boiler pressure | 12 bar | 14 bar |
| Expansion type | compound | |
| Cylinders | four, HP: 355 x 640 mm and LP: 550 x 640 mm | four, HP: 350 x 640 mm and LP: 550 x 640 mm |
Power
| Property | 181-186 | 187-196 |
|---|---|---|
| Power source | steam | |
| Estimated power | 400 kW (544 PS) | 405 kW (551 PS) |
| Top speed | 55 km/h | |
| Starting effort | 90.7 kN | 110.7 kN |
| Starting effort simple | 108.9 kN | 132.8 kN |
Calculated values
| Property | 181-186 | 187-196 |
|---|---|---|
| Factor of adhesion | 1 : 6.53 | 1 : 5.21 |
| Optimal speed | 27 km/h | 23 km/h |
| Power-to-weight ratio | 6.6 kW/t | 6.9 kW/t |
| Heating Surface Equivalent | 159.8 m² | 149.0 m² |
| Cylinder volume/HSE | 1 : 1,744.35 | 1 : 1,847.00 |
| Adhesive weight/Total | 1 : 1.00 | |
| Tractive force/Heating surface | 1 : 15.69 | 1 : 20.55 |
| Grate area/Heating surface | 1 : 67.11 | 1 : 66.18 |
| Firebox/Tube surface | 1 : 14.49 | 1 : 14.41 |