Nickel Plate Road class H-6
United States 1918 86 produced
After the Nickel Plate Road class H-5 of 1917, the next ten H-6a were USRA Light Mikados, delivered by ALCO. In the years 1920 to 1924, Lima delivered the classes H-6b to H-6f, which were virtually identical to each other and totaled 61 units. 15 more, which were again USRA Light Mikados, came to the NKP in 1923 via the acquisition of the Lake Erie & Western and became the class H-6o.
Over time, individual Mikados were equipped with mechanical stokers and larger tenders. The fireboxes were also changed. For most of them, the service life ended in the forties. Today 587, 624 and 639 are preserved, with the 587 having been operational for a longer period since 1988.
Technical data
General
| Property | H-6a | H-6b to f | H-6o |
|---|---|---|---|
| Built | 1918 | 1920-1924 | 1924 |
| Manufacturers | ALCO | Lima | Baldwin |
| Wheel arrangement | 2-8-2 (Mikado) | ||
| Gauge | 1,435 mm (Standard gauge) | ||
Dimensions and weights
| Property | H-6a | H-6b to f | H-6o |
|---|---|---|---|
| Wheelbase | 11.00 m | ||
| Total wheelbase | 21.76 m | ||
| Service mass | 127.9 t | 138.5 t | 127.9 t |
| Adhesion mass | 99.8 t | 103.2 t | 99.8 t |
| Total mass | 209.7 t | 299.6 t | 209.7 t |
| Rigid wheelbase | 5.11 m | ||
| Axle load | 24.9 t | 26.5 t | 24.9 t |
| Water capacity | 37,854 l | 83,279 l | 37,854 l |
| Fuel capacity | 14.5 t (coal) | 18.1 t (coal) | 14.5 t (coal) |
Boiler
| Property | H-6a | H-6b to f | H-6o |
|---|---|---|---|
| Grate area | 6.197 m² | ||
| Firebox surface | 26.013 m² | ||
| Tube heating surface | 321.816 m² | 324.882 m² | |
| Evaporative heating surface | 347.829 m² | 350.895 m² | |
| Superheater surface | 81.941 m² | ||
| Total heating surface | 429.8 m² | 432.8 m² | |
Power plant
| Property | H-6a | H-6b to f | H-6o |
|---|---|---|---|
| Driver diameter | 1,600 mm | ||
| Boiler pressure | 13.8 bar | ||
| Expansion type | simple expansion | ||
| Cylinders | two, 660 x 762 mm | ||
Power
| Property | H-6a | H-6b to f | H-6o |
|---|---|---|---|
| Power source | steam | ||
| Estimated power | 2,192 kW (2,980 PS) | 2,200 kW (2,991 PS) | |
| Starting effort | 243.4 kN | ||
Calculated values
| Property | H-6a | H-6b to f | H-6o |
|---|---|---|---|
| Factor of adhesion | 1 : 4.02 | 1 : 4.16 | 1 : 4.02 |
| Optimal speed | 55 km/h | ||
| Power-to-weight ratio | 17.1 kW/t | 15.8 kW/t | 17.2 kW/t |
| Heating Surface Equivalent | 641.8 m² | 644.8 m² | |
| Cylinder volume/HSE | 1 : 813.40 | 1 : 809.54 | |
| Adhesive weight/Total | 1 : 1.28 | 1 : 1.34 | 1 : 1.28 |
| Tractive force/Heating surface | 1 : 11.83 | 1 : 11.75 | |
| Grate area/Heating surface | 1 : 69.35 | 1 : 69.85 | |
| Firebox/Tube surface | 1 : 12.37 | 1 : 12.49 | |
| Total/Superheater | 1 : 4.24 | 1 : 4.28 | |
