Southern Railway (USA) class Ls-2
United States 1926 9 produced
Based on the class Ls-1 Mallets, the Southern had the No. 4050 built in 1926 with simple expansion and a slightly smaller boiler. Since this proved its worth, four Ls-1 were also rebuilt to simple expansion and in 1928 a further eight locomotives were built again with a larger boiler. This was more efficient mainly because of the thermic syphons. They also received larger tenders and now formed the class Ls-2. They were the Southern's most powerful locomotives and were also used on the almost five percent steep Saluda Grade.
Technical data
General
| Property | 4050 | 4051-4058 |
|---|---|---|
| Built | 1926 | 1928 |
| Manufacturers | Baldwin | |
| Wheel arrangement | 2-8-8-2 (Mikado Mallet) | |
| Gauge | 1,435 mm (Standard gauge) | |
Dimensions and weights
| Property | 4050 | 4051-4058 |
|---|---|---|
| Wheelbase | 17.30 m | |
| Service mass | 203.2 t | 212.7 t |
| Adhesion mass | 176.9 t | 185.5 t |
| Total mass | 321.9 t | 299.6 t |
| Rigid wheelbase | 4.70 m | |
| Water capacity | 37,854 l | 52,996 l |
| Fuel capacity | 14.5 t (coal) | |
Boiler
| Property | 4050 | 4051-4058 |
|---|---|---|
| Grate area | 7.711 m² | 7.692 m² |
| Firebox surface | 31.123 m² | 40.506 m² |
| Tube heating surface | 417.135 m² | 421.78 m² |
| Evaporative heating surface | 448.258 m² | 462.286 m² |
| Superheater surface | 125.419 m² | 131.922 m² |
| Total heating surface | 573.7 m² | 594.2 m² |
Power plant
| Property | 4050 | 4051-4058 |
|---|---|---|
| Driver diameter | 1,448 mm | |
| Boiler pressure | 14.5 bar | |
| Expansion type | simple expansion | |
| Cylinders | four, 584 x 762 mm | |
Power
| Property | 4050 | 4051-4058 |
|---|---|---|
| Power source | steam | |
| Estimated power | 2,386 kW (3,244 PS) | 2,610 kW (3,549 PS) |
| Starting effort | 442.1 kN | |
Calculated values
| Property | 4050 | 4051-4058 |
|---|---|---|
| Factor of adhesion | 1 : 3.93 | 1 : 4.12 |
| Optimal speed | 34 km/h | 35 km/h |
| Power-to-weight ratio | 11.7 kW/t | 12.3 kW/t |
| Heating Surface Equivalent | 854.7 m² | 928.7 m² |
| Cylinder volume/HSE | 1 : 955.89 | 1 : 879.77 |
| Adhesive weight/Total | 1 : 1.15 | |
| Tractive force/Heating surface | 1 : 16.10 | 1 : 15.54 |
| Grate area/Heating surface | 1 : 74.40 | 1 : 77.25 |
| Firebox/Tube surface | 1 : 13.40 | 1 : 10.41 |
| Total/Superheater | 1 : 3.57 | 1 : 3.50 |
