| Pennsylvania Railroad D7 | |
| Powertype: | Steam |
| Whytetype: | 4-4-0 |
| Uicclass: | 2′B |
| Builddate: | 1882–1891 |
| Builder: | PRR Altoona Works |
| Totalproduction: | 58 D7, 61 D7a |
| Leadingdiameter: | 300NaN0 (D7)[1] 330NaN0 (D7a)[2] |
| Driverdiameter: | 680NaN0 (D7) 620NaN0 (D7a) |
| Wheelbase: | 22feet |
| Length: | 58feet |
| Height: | 14feet |
| Axleload: | 326501NaN1 |
| Weightondrivers: | 567001NaN1 (D7) 587001NaN1 |
| Locoweight: | 935001NaN1 (D7) 963301NaN1 (D7a) |
| Locotenderweight: | 1608801NaN1 |
| Fueltype: | Anthracite coal |
| Fuelcap: | 120001NaN1 |
| Watercap: | 2400USgal |
| Boilerpressure: | 140-1NaN-1 |
| Firearea: | 34.752NaN2 |
| Tubearea: | 11342NaN2 |
| Fireboxarea: | 1552NaN2 |
| Totalsurface: | 12892NaN2 |
| Cylindercount: | 2 |
| Cylindersize: | 17x |
| Valvegear: | Stephenson |
| Valvetype: | Slide valves |
| Tractiveeffort: | 121382NaN2 (D7) 133132NaN2 (D6a) |
| Factorofadhesion: | 4.7 (D7) 4.4 (D7a) |
Class D7 (formerly Class A (anthracite), pre-1895) on the Pennsylvania Railroad was a class of 4-4-0 steam locomotive.[3] Fifty-eight were built by the PRR's Altoona Works (now owned by Norfolk Southern) between 1882–1891 with 682NaN2 drivers, while sixty-one of class D7a were constructed with 622NaN2 drivers.[4]
The D7 was fundamentally an anthracite-burning version of the PRR D6, with a larger fire-grate in order to burn the slower-burning, harder coal.[5]
