Pennsylvania classes H8, H9 and H10
From 1907 onwards, the PRR started with procuring 540 Consolidations of classes H8 to H8c, most of which were still operated with saturated steam. In addition, 146 of them had already been built as H8sb or H8sc with superheaters. Most of the others were also soon superheated. From 1913 onwards, 274 H9s and 273 H10s followed, all of which had a superheater from the factory, most of which were similar to the superheated H8 and differed in the size of the valve ports. In addition, 312 H8 were rebuilt into H9s and 200 more H8 were rebuilt into H10s. Baldwin, the ALCO plants in Pittsburgh and Brooks, and the PRR Juniata shops in Altoona were involved in the production of the individual variants. The retirements began in 1933 and were completed by 1960.
Technical data
General
| Property | H8a | H8sb | H9s | H10s |
|---|---|---|---|---|
| Built | 1907-1913 | 1913-1914 | 1913-1916 | |
| Manufacturers | Altoona, ALCO, Baldwin | ALCO, Baldwin, Lima | Baldwin, Altoona | ALCO, Baldwin, Lima |
| Wheel arrangement | 2-8-0 (Consolidation) | |||
| Gauge | 1,435 mm (Standard gauge) | |||
Dimensions and weights
| Property | H8a | H8sb | H9s | H10s |
|---|---|---|---|---|
| Wheelbase | 7.87 m | |||
| Total wheelbase | 18.09 m | 19.03 m | 19.05 m | 19.03 m |
| Service mass | 109.3 t | 114.5 t | 113.4 t | 113.2 t |
| Adhesion mass | 98.2 t | 102.1 t | 99.8 t | 102.9 t |
| Total mass | 181.4 t | 186.7 t | 176.4 t | 195.5 t |
| Rigid wheelbase | 5.19 m | |||
| Axle load | 28.3 t | 27.7 t | 28.3 t | 27.2 t |
| Water capacity | 26,498 l | 34,069 l | 30,662 l | |
| Fuel capacity | 11.3 t (coal) | 15.4 t (coal) | ||
Boiler
| Property | H8a | H8sb | H9s | H10s |
|---|---|---|---|---|
| Grate area | 5.118 m² | |||
| Firebox surface | 17.837 m² | 19.603 m² | ||
| Tube heating surface | 339.282 m² | 265.61 m² | ||
| Evaporative heating surface | 357.12 m² | 285.213 m² | ||
| Total heating surface | 357.1 m² | 342.2 m² | ||
| Superheater surface | 56.95 m² | |||
Power plant
| Property | H8a | H8sb | H9s | H10s |
|---|---|---|---|---|
| Driver diameter | 1,575 mm | |||
| Boiler pressure | 14.1 bar | |||
| Expansion type | simple expansion | |||
| Cylinders | two, 610 x 711 mm | two, 635 x 711 mm | two, 660 x 711 mm | |
Power
| Property | H8a | H8sb | H9s | H10s |
|---|---|---|---|---|
| Power source | steam | |||
| Estimated power | 1,417 kW | 1,641 kW | 1,715 kW | |
| Starting effort | 201.6 kN | 218.8 kN | 236.6 kN | |
Calculated values
| Property | H8a | H8sb | H9s | H10s |
|---|---|---|---|---|
| Factor of adhesion | 1 : 4.78 | 1 : 4.97 | 1 : 4.47 | 1 : 4.27 |
| Optimal speed | 43 km/h | 50 km/h | 47 km/h | 45 km/h |
| Power-to-weight ratio | 13.0 kW/t | 14.3 kW/t | 14.5 kW/t | 15.2 kW/t |
| Heating Surface Equivalent | 446.3 m² | 497.1 m² | ||
| Cylinder volume/HSE | 1 : 930.19 | 1 : 835.09 | 1 : 906.13 | 1 : 980.07 |
| Adhesive weight/Total | 1 : 1.11 | 1 : 1.12 | 1 : 1.14 | 1 : 1.10 |
| Tractive force/Heating surface | 1 : 11.79 | 1 : 12.31 | 1 : 13.35 | 1 : 14.44 |
| Grate area/Heating surface | 1 : 69.78 | 1 : 66.85 | ||
| Firebox/Tube surface | 1 : 19.02 | 1 : 13.55 | ||
| Total/Superheater | 1 : 5.01 | |||