Rebuilt 2-8-4s that became very successful freight engines.
See http://www.steamlocomotive.com/northern/mp.html (visited 7 Jan 2003), where Wes Barris says they had cast-steel beds and roller bearings.
Firebox heating surface included 136 sq ft of thermic syphons. These freight engines were based on the Denver and Rio Grande Western's 1800-class 4-8-4s, with a little Northern Pacific A-5 blended in. They lasted until 1956.
Another 4-8-4 class on the MP's roster were the 2101-2125, which were rebuilds from 63-in DD 2-8-4 Berkshires to 75-in driver 4-8-4s. (see separate entry).
| Specifications | ||
|---|---|---|
| Class | 2101 | 26S-63 |
| Locobase ID | 1372 | 266 |
| Railroad | Missouri Pacific (MP) | Missouri Pacific (MP) |
| Whyte | 4-8-4 | 4-8-4 |
| Road Numbers | 2101-2125 | 2201-2215 |
| Gauge | Std | Std |
| Builder | MP | Baldwin |
| Year | 1940 | 1943 |
| Valve Gear | Baker | Walschaert |
| Locomotive Length and Weight | ||
| Driver Wheelbase | 19.50' | 19.25' |
| Engine Wheelbase | 45.17' | 47.08' |
| Ratio of driving wheelbase to overall engine wheebase | 0.43 | 0.41 |
| Overall Wheelbase (engine & tender) | 89.81' | 93.48' |
| Axle Loading (Maximum Weight per Axle) | ||
| Weight on Drivers | 279300 lbs | 279400 lbs |
| Engine Weight | 445950 lbs | 489000 lbs |
| Tender Light Weight | 287700 lbs | |
| Total Engine and Tender Weight | 0 | 776700 lbs |
| Tender Water Capacity | 17250 gals | 19350 gals |
| Tender Fuel Capacity (oil/coal) | 20 tons | 20 tons |
| Minimum weight per yard of rail on which locomotive could run | 116.38 lb rail | 116.42 lb rail |
| Geometry Relating to Tractive Effort | ||
| Driver Diameter | 75" | 73" |
| Boiler Pressure | 250 psi | 290.10 psi |
| Cylinders (dia x stroke) | 28" x 30" | 26" x 30" |
| Tractive Effort | 66640 lbs | 68503 lbs |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.19 | 4.08 |
| Heating Ability | ||
| Firebox Area | 484 sq. ft | 559 sq. ft |
| Grate Area | 88.30 sq. ft | 106 sq. ft |
| Evaporative Heating Surface | 4839 | 5306 |
| Superheating Surface | 1938 | 2200 |
| Combined Heating Surface | 6777 | 7506 |
| Evaporative Heating Surface/Cylinder Volume | 226.33 | 287.82 |
| Computations Relating to Power Output (More Information) | ||
| Robert LeMassena's Power Computation | 22075 | 30750.60 |
| Same as above plus superheater percentage | 28387.73 | 39763.57 |
| Same as above but substitute firebox area for grate area | 155602.04 | 209696.54 |
| Power L1 | 36103.65 | 53418.91 |
| Power MT | 1139.92 | 1686.02 |
| This page last modified: . | [Contact] | All material © 1999-2008 SteamLocomotive.com |