Lehigh Valley classes T-1 to T-3
United States 1931 47 produced
The Lehigh Valley used the 4-8-4, which they dubbed “Wyoming” after the Wyoming Valley in Pennsylvania, primarily for freight trains. After one prototype each from Baldwin and ALCO, ten more were procured as T-1a and T-2a. These had the most powerful booster of all US steam locomotives in the rear bogie. The T-3 was built by Baldwin from 1934 and was also suitable for passenger trains with larger wheels. The T-2b first emerged during World War II and was derived from the T-2a. Due to the lack of material, however, this was less refined and thus weighed more.
Technical data
General
| Property | T-1a | T-2a | T-2b | T-3 |
|---|---|---|---|---|
| Built | 1931-1932 | 1943 | 1934-1935 | |
| Manufacturers | Baldwin | ALCO | Baldwin | |
| Wheel arrangement | 4-8-4 (Northern) | |||
| Gauge | 1,435 mm (Standard gauge) | |||
Dimensions and weights
| Property | T-1a | T-2a | T-2b | T-3 |
|---|---|---|---|---|
| Wheelbase | 13.69 m | 13.89 m | 14.00 m | |
| Total wheelbase | 28.92 m | 29.10 m | 28.96 m | 29.01 m |
| Service mass | 187.4 t | 191.4 t | 204.6 t | 197.3 t |
| Adhesion mass | 122.5 t | 121.6 t | 124.5 t | 123.5 t |
| Total mass | 368.1 t | 354.2 t | 381.1 t | 373.8 t |
| Rigid wheelbase | 5.87 m | 6.10 m | ||
| Axle load | 30.6 t | 30.4 t | 31.1 t | 31 t |
| Water capacity | 75,708 l | 68,137 l | 75,708 l | |
| Fuel capacity | 27.2 t (coal) | 25.4 t (coal) | 27.2 t (coal) | |
Boiler
| Property | T-1a | T-2a | T-2b | T-3 |
|---|---|---|---|---|
| Grate area | 8.203 m² | 8.965 m² | ||
| Firebox surface | 45.523 m² | 47.195 m² | 45.894 m² | 47.102 m² |
| Tube heating surface | 458.198 m² | 458.291 m² | 453.553 m² | 458.198 m² |
| Evaporative heating surface | 503.721 m² | 505.486 m² | 499.447 m² | 505.3 m² |
| Superheater surface | 209.589 m² | 208.382 m² | 194.632 m² | 191.009 m² |
| Total heating surface | 713.3 m² | 713.9 m² | 694.1 m² | 696.3 m² |
Power plant
| Property | T-1a | T-2a | T-2b | T-3 |
|---|---|---|---|---|
| Driver diameter | 1,778 mm | 1,956 mm | ||
| Boiler pressure | 17.2 bar | 17.6 bar | 19 bar | |
| Expansion type | simple expansion | |||
| Cylinders | two, 686 x 762 mm | two, 660 x 813 mm | two, 686 x 762 mm | |
Power
| Property | T-1a | T-2a | T-2b | T-3 |
|---|---|---|---|---|
| Power source | steam | |||
| Estimated power | 3,281 kW (4,461 PS) | 3,337 kW (4,537 PS) | 3,430 kW (4,664 PS) | 3,729 kW (5,070 PS) |
| Starting effort | 295.3 kN | 298.0 kN | 295.3 kN | |
| Starting effort booster | 81.669 kN | 54.713 kN | ||
Calculated values
| Property | T-1a | T-2a | T-2b | T-3 |
|---|---|---|---|---|
| Factor of adhesion | 1 : 4.07 | 1 : 4.00 | 1 : 4.10 | |
| Optimal speed | 68 km/h | 69 km/h | 71 km/h | 77 km/h |
| Power-to-weight ratio | 17.5 kW/t | 17.4 kW/t | 16.8 kW/t | 18.9 kW/t |
| Heating Surface Equivalent | 1,150.5 m² | 1,158.2 m² | 1,118.2 m² | 1,122.8 m² |
| Cylinder volume/HSE | 1 : 489.30 | 1 : 480.76 | 1 : 497.97 | 1 : 501.37 |
| Adhesive weight/Total | 1 : 1.53 | 1 : 1.57 | 1 : 1.64 | 1 : 1.60 |
| Tractive force/Heating surface | 1 : 8.65 | 1 : 8.72 | 1 : 8.97 | 1 : 8.86 |
| Grate area/Heating surface | 1 : 86.96 | 1 : 87.03 | 1 : 84.61 | 1 : 77.67 |
| Firebox/Tube surface | 1 : 10.07 | 1 : 9.71 | 1 : 9.88 | 1 : 9.73 |
| Total/Superheater | 1 : 2.40 | 1 : 2.43 | 1 : 2.57 | 1 : 2.65 |
