Pennsylvania 2-10-2 "Santa Fe" Locomotives of the USA

The Pennsylvania Railroad took delivery of sixty "Santa Fe" type locomotives during 1918 and 1919. These locomotives had 62" diameter drivers, 30" x 32" cylinders, a 215 psi boiler pressure, they exerted 84,890 pounds of tractive effort and each weighed 435,000 pounds. The American Locomotive Company built sixteen of them in 1918 and nineteen in 1919. The Baldwin Locomotive Works built twenty-five of them in 1919. These 2-10-2s were designed for heavy freight service on the Lines West. They had flangeless center drivers and lateral-motion axle boxes on the front and rear driver sets to allow them to negotiate 22 degree curves. They also had Belpaire fireboxes.

Also in 1919 the USRA allocated 130 "Santa Fe-Heavy" locomotives to the PRR. These locomotives had 63" diameter drivers, 30 x 32 cylinders, a 190 psi boiler pressure, they exerted 73,829 pounds of tractive effort and each weighed 384,225 pounds. ALCO built one hundred of these 2-10-2s and Baldwin built the other thirty.

In the mid 1920s the PRR rebuilt its USRA allocated "Santa Fe" locomotives to include a Belpaire firebox. The PRR was one of the few American railroads to use this type of firebox. Most steam locomotive had a boiler that was continuously round from the front of the locomotive through and including the firebox. This meant that the staybolts used to hold the firebox in place had to be of various lengths to connect the rectangular shaped firebox to the round boiler jacket, which complicated maintenance. Locomotives with a Belpaire firebox had boiler, which was square shaped over the firebox. This design permitted the use of staybolts of the same length and the interior of the firebox allowed for more heating surface.

There are no surviving PRR 2-10-2 "Santa Fe" type locomotives.

Roster by Richard Duley

ClassQty.Road NumbersYear BuiltBuilderNotes
N1607008 . 98661918-1919ALCO, BaldwinSee chart below for Class N1 road numbers and disposition.
N21307036 . 200431919ALCO, BaldwinUSRA allocated .Santa Fe-Heavy. locomotives. See chart below for Class N2 road numbers and disposition.

Class N1 and Class N2 Road Numbers
ClassQty. Road NumbersYear BuiltBuilderNotes
N11670087025708671177128722072287242724572471918ALCO 1
97249725972617331734073427344734574181919 ALCO 1
20 74817613 7637 7646 7697922292289234935393651919 Baldwin 2
5970497059706970897091919ALCO 2
197101919Baldwin 3
2972197221919ALCO 3
197241919Baldwin 4
39730975297531919ALCO 5
39860986198661919Baldwin 6
N22703670821919Baldwin 3
171041919ALCO 7
771237126713971817190721272631919Baldwin 8
172651919ALCO 7
67268726972767377728172821919Baldwin 5
37283728472851919ALCO 9
37286732673431919Baldwin 8
18763579097910791779217927 79377944796180081919ALCO 8
180441919Baldwin 10
1280708095809881058110814081448147814981621919ALCO 9
2818481961919Baldwin 11
182061919ALCO 12
182081919Baldwin 3
2821582231919ALCO 2
182271919Baldwin 3
582318241825382558258 1919ALCO 13
182631919Baldwin 7
38266826882991919ALCO 14
483168337836083711919Baldwin 8
183761919ALCO 10
1 83791919Baldwin 10
14 83898393840884258794889588968901890389051919ALCO 9
1 89091919Baldwin 12
39 8912891689208929973898459854985820003200401919ALCO 8

Notes for the Class N1 and Class N2 Road Numbers chart.

  1. Scrapped between 1947 and 1950.
  2. Scrapped between 1948 and 1950.
  3. Scrapped in 1949.
  4. Scrapped in 1947.
  5. Scrapped between 1949 and 1950.
  6. Scrapped between 1948 and 1950.
  7. Scrapped in 1953.
  8. Scrapped between 1949 and 1953.
  9. Scrapped between 1948 and 1953
  10. Scrapped in 1952
  11. #8184 scrapped in 1953. #8196 scrapped in 1948.
  12. Scrapped in 1950
  13. Scrapped between 1949 and 1952.
  14. Scrapped between 1950 and 1953.

Class Details by Steve Llanso of Sweat House Media

Class N1s (Locobase 82)

Data from Rob Schoenberg diagram collection then at, visited December 2002. See also DeGolyer, Volume 59, pp. 326.

Baldwin (25) and Brooks (35) both built engines in this class that William D Edson (Keystone Steam & Electric, 1974) says were built to serve the Lines West requirement for heavy freight movement out of the Lake ports. One stringent requirement was the need to be able to negotiate 22-deg curves, accomplished by using flangeless center drivers and lateral-motion axle boxes on the front and rear driver set.

Of course, if it's Pennsy, it must have a Belpaire boiler. (See Locobase 32 for a comment on the unique design of Pennsy's Belpaire firebox.). Firebox heating surface area included 126 sq ft (11.7 sq m) in the combustion chamber and 43 sq ft (4 sq m). Fourteen-inch (356 mm) piston valves admitted steam to the cylinders.

Like most Pennsy steam, these locomotives operated into the late 1940s.

Class N2s (Locobase 1425)

Data from Rob Schoenberg's (visited December 2002), which reproduces the 1928 diagrams and thus the dimensions after reconstruction with the Belpaire firebox.

Firebox had combustion chamber. The more widely emulated of the two USRA "Santa Fe" designs. Delivered originally with radial-stay fireboxes, these engines received the typical Pennsy Belpaire-type firebox in 1923. See Locobase 32 for a comment on the unique design of Pennsy's Belpaire firebox.

Eugene Huddleston (Trains, March 1991), writing about this design, comments that the Pennsy found that when assigned trains in accordance with their tractive power, these engines "handled their tonnage in a satisfactory manner."

Specifications by Steve Llanso of Sweat House Media
Locobase ID82 1425
RailroadPennsylvania (PRR)Pennsylvania (PRR)
Number in Class60130
Road Numbers7008+7036+
Number Built60130
Valve GearWalschaertSouthern
Locomotive Length and Weight
Driver Wheelbase (ft)22.1722.33
Engine Wheelbase (ft)41.9642.17
Ratio of driving wheelbase to overall engine wheebase 0.53 0.53
Overall Wheelbase (engine & tender) (ft)82.7782.87
Axle Loading (Maximum Weight per Axle) (lbs)75,60063,200
Weight on Drivers (lbs)351,000297,000
Engine Weight (lbs)435,000380,700
Tender Loaded Weight (lbs)206,100211,200
Total Engine and Tender Weight (lbs)641,100591,900
Tender Water Capacity (gals)960012,000
Tender Fuel Capacity (oil/coal) (gals/tons)19.7016.90
Minimum weight of rail (calculated) (lb/yd)11799
Geometry Relating to Tractive Effort
Driver Diameter (in)6263
Boiler Pressure (psi)215190
High Pressure Cylinders (dia x stroke) (in)30" x 32"30" x 32"
Tractive Effort (lbs)84,89073,829
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.13 4.02
Heating Ability
Firebox Area (sq ft)429420
Grate Area (sq ft)8083.20
Evaporative Heating Surface (sq ft)47384980
Superheating Surface (sq ft)13871222
Combined Heating Surface (sq ft)61256202
Evaporative Heating Surface/Cylinder Volume180.98190.22
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation17,20015,808
Same as above plus superheater percentage21,15618,970
Same as above but substitute firebox area for grate area113,44995,760
Power L116,43413,776
Power MT516.11511.29



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