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Southern Pacific classes AC-4, AC-5 and AC-6
After the Southern Pacific had already rebuilt several Cab Forward 2-8-8-2 Mallets into simple articulated, the 1928 AC-4 was the first class to be built as a simple expansion Cab Forward from the start. Superintenden...
| Southern Pacific classes AC-4, AC-5 and AC-6Remove | |
|---|---|
| Variant | AC-4, AC-5 |
| Built | 1928 |
| Manufacturers | Baldwin |
| Wheel arrangement | 2D(D1) ma |
| Gauge | 1435 mm |
| Length | |
| Service mass | 278778 kg |
| Top speed | |
| Power | |
| Engine |
General
| Property | Southern Pacific classes AC-4, AC-5 and AC-6AC-4, AC-5 |
|---|---|
| Built | 1928 |
| Manufacturers | Baldwin |
| Wheel arrangement | 4-8-8-2 |
| Gauge | 1,435 mm |
Dimensions and weights
| Property | Southern Pacific classes AC-4, AC-5 and AC-6AC-4, AC-5 |
|---|---|
| Length loco | 23.76 m |
| Wheelbase | 20.37 m |
| Total wheelbase | 32.44 m |
| Service mass | 278.8 t |
| Adhesion mass | 215.5 t |
| Total mass | 397.2 t |
| Rigid wheelbase | 5.16 m |
| Axle load | 27.4 t |
| Water capacity | 61,142 l |
| Fuel capacity | 18,594 l (oil) |
Boiler
| Property | Southern Pacific classes AC-4, AC-5 and AC-6AC-4, AC-5 |
|---|---|
| Grate area | 12.914 m² |
| Firebox surface | 47.659 m² |
| Tube heating surface | 604.521 m² |
| Evaporative heating surface | 652.18 m² |
| Superheater surface | 277.687 m² |
| Total heating surface | 929.9 m² |
Power plant
| Property | Southern Pacific classes AC-4, AC-5 and AC-6AC-4, AC-5 |
|---|---|
| Driver diameter | 1,613 mm |
| Boiler pressure | 16.2 bar |
| Expansion type | simple expansion |
| Cylinders | four, 610 x 813 mm |
Power
| Property | Southern Pacific classes AC-4, AC-5 and AC-6AC-4, AC-5 |
|---|---|
| Power source | steam |
| Indicated power | 4,206 kW (5,719 PS) |
| Starting effort | 515.8 kN |
Calculated values
| Property | Southern Pacific classes AC-4, AC-5 and AC-6AC-4, AC-5 |
|---|---|
| Factor of adhesion | 1 : 4.10 |
| Optimal speed | 50 km/h |
| Power-to-weight ratio | 15.1 kW/t |
| Heating Surface Equivalent | 1,445.8 m² |
| Cylinder volume/HSE | 1 : 656.30 |
| Adhesive weight/Total | 1 : 1.29 |
| Tractive force/Heating surface | 1 : 11.59 |
| Grate area/Heating surface | 1 : 72.00 |
| Firebox/Tube surface | 1 : 12.68 |
| Total/Superheater | 1 : 2.35 |
