Cape Government Railways Fairlie
The first articulated locomotive ever to be operational in Africa was a six-axle Double Fairlie built by Avonside in 1875 for the CGR. This locomotive, numbered E33, was also the first locomotive in Africa with Walschaerts valve gear. It was ordered for mainlines around East London which had steep inclines.
In trials against two permanently-coupled 0-6-0T locomotives, it showed better running qualities on downhill stretches and a better fuel economy. But like all Double Fairlies, it had very limited space in the cab what made it very unpopular with crews. But in general, it was still called a successful design with some improvements to be made in the area of the joints, bogies, sandboxes and water capacity.
In 1878, a second locomotive numbered E34 was delivered that incorporated most of the suggested improvements, but without a larger water capacity. More water could be loaded into a separate tender. The biggest point of criticism was still the cramped cab, and so both locomotives were quickly removed from mainline service and used as shunters. Both were scrapped in 1903.
Technical data
General
| Property | E33 | E34 |
|---|---|---|
| Built | 1875 | 1878 |
| Manufacturers | Avonside | |
| Wheel arrangement | 0-6-6-0T (Double Fairlie) | |
| Gauge | 1,067 mm (Cape gauge) | |
Dimensions and weights
| Property | E33 | E34 |
|---|---|---|
| Length | 13.77 m | 11.43 m |
| Wheelbase | 8.84 m | 7.67 m |
| Service mass | 36.6 t | |
| Adhesion mass | 36.6 t | |
| Rigid wheelbase | 2.29 m | |
| Axle load | 6.1 t | |
| Water capacity | 3,819 l | |
| Fuel capacity | 2.1 t (coal) | 1.3 t (coal) |
Boiler
| Property | E33 | E34 |
|---|---|---|
| Grate area | 1.301 m² | |
| Firebox surface | 8.361 m² | |
| Tube heating surface | 84.356 m² | |
| Evaporative heating surface | 92.717 m² | |
| Total heating surface | 92.7 m² | |
Power plant
| Property | E33 | E34 |
|---|---|---|
| Driver diameter | 991 mm | 1,003 mm |
| Boiler pressure | 9.3 bar | 9 bar |
| Expansion type | simple expansion | |
| Cylinders | four, 292 x 457 mm | |
Power
| Property | E33 | E34 |
|---|---|---|
| Power source | steam | |
| Estimated power | 186 kW (253 PS) | |
| Starting effort | 62.3 kN | 59.2 kN |
Calculated values
| Property | E33 | E34 |
|---|---|---|
| Factor of adhesion | 1 : 5.76 | 1 : 6.06 |
| Optimal speed | 18 km/h | 19 km/h |
| Power-to-weight ratio | 5.1 kW/t | |
| Heating Surface Equivalent | 134.5 m² | |
| Cylinder volume/HSE | 1 : 911.02 | |
| Adhesive weight/Total | 1 : 1.00 | |
| Tractive force/Heating surface | 1 : 14.04 | 1 : 13.35 |
| Grate area/Heating surface | 1 : 71.27 | |
| Firebox/Tube surface | 1 : 10.09 | |