Rock Island 4-8-4 "Northern" Type Locomotives

Introduction

To test the 4-8-4 wheel arrangement on its railroad, the Chicago, Rock Island & Pacific Railroad bought one Class R-67a 4-8-4 (road number 5000) from the American Locomotive Company in 1929. The locomotive performed so well that CRI&P bought 24 more (Class R-67b) before the year ended (road numbers 5001 through 5024). In 1930, 40 more (road numbers 5025 through 5064) were purchased from ALCO.

These 65 locomotives had 69" drivers, 26 x 32 cylinders, a boiler pressure of 250 psi, weighed about 437,000 lbs and had a tractive effort of 66,620 pounds. Although designed for freight trains they were also used in passenger service and some were rebuilt with 73" drivers to provide more speed when used on passenger trains.

In 1944, CRI&P took delivery of ten more Northerns (road numbers 5100 through 5109) and in 1946, ten more (road numbers 5110 through 5119). All twenty of these Class R67-b Northerns came from ALCO. The first ten were oil burners and the last ten were delivered as coal burners. These 20 locomotives had 74" drivers, 26 x 32 cylinders, a boiler pressure of 270 psi, a weight of 474,500 lbs and a tractive effort of 67,088 pounds.

The CRI&P had the largest fleet (85) of these locomotives in the United States and was second to the Canadian National Railroad in North America and third to the USSR in the world. No CRI&P Northerns were saved.

Roster by Richard Duley

ClassRoad NumbersYear BuiltBuilder
R-67a50001929ALCO
R-67b5001-50241929ALCO
R-67b5025-50641930ALCO
R-67b5100-51091944ALCO
R-67b5110-51191946ALCO

Class Details by Steve Llanso

Class R-65A, B, C/R-67 (Locobase 250)

Data from 1930 Locomotive Cyclopedia, supplemented by RI 1- 1942 and RI-9 1952 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection. (Thanks to Chris Hohl for his 22 February 2013 inquiry about this class that led me to tighten up the entry.)

Schenectady delivered the first two batches in 1929, the third in 1930. Works numbers were 67670 inFebruary 1929, 68003-68004 in July, 68005-68020 in August, 68021-68023 in September, 68024-68026 in October, 68288-68291 in March 1930, 68292-68326 in April, 68327 in May.

Firebox had 150 sq ft (13.9 sq m) of thermic syphons, Coffin feedwater heaters, and Chambers front end throttle. All of the class received 74" drivers by 1944, which led to their class ID changing to R-67. The 1952 diagrams indicate that locomotives fitted with an auxiliary booster engine on the trailing truck were designated R-67-B, those without were simply R-67.

According to Drury (1993), this design's size and weight limited their operation to the Chicago-Des Moines corridor, the Chicago-Dalhart, Texas line, and the segment between Herington, Kan and El Reno, Okla. Later bridge-strengthening allowed these heavyweights to pull freights and passenger trains to Denver, Fort Worth, Tucumcari, and Minneapolis. Ten of this large stud of Northerns (the largest on a North American road) received a larger tender, roller bearings, and thicker driver tires.

Class R-67 (Locobase 251)

Data from 1947 Locomotive Cyclopedia, supplemented by RI 9 - 1952 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection. (Thanks to Chris Hohl for his 22 February 2013 inquiry about this class that led me to tighten up the entry.) The first ten were produced in 1944 (Order S-1920, works numbers were 719450-71948 in April 1944 and 71949-71954 in May.), the last ten in 1946 (Order S-1984, works numbers were 74366-74367 in January 1946, 74368-74369 in April, 74370-74374 in May, 74375 in June).

Firebox had four thermic syphons that totalled 155 sq ft (14.4 sq m). Piston valves measured a relatively small 12" (306 mm) in diameter.

Note that these twenty locomotives, built fifteen years after the earlier R-67-B group, had much less superheating area and older ratio of tubes to flues. Cylinder volume and driver diameter remained the same, but boiler pressure increased by 20 psi (1.38 bar). Wartime restrictions on high-temperature alloys probably had something to do with that retrograde. Another possibility is that reported difficulties in maintaining Type E superheaters may have prompted the change.

In fact, the class strongly resembles the Delaware & Hudson K-62s built at the same time by the same builder. Among more modern features these engines showed were roller bearings on all axles and Boxpok drivers.

The first ten engines were oil-fired, the last ten burned coal. The tenders for each group held the same amount of water, but the latter group's tenders carried 22 tons (20 metric tons) of coal.


Specifications by Steve Llanso
ClassR-65A, B, C/R-67R-67
Locobase ID250 251
RailroadRock Island (CRI & P)Rock Island (CRI & P)
CountryUSAUSA
Whyte4-8-44-8-4
Road Numbers5000-50645100-5119
GaugeStdStd
BuilderAlco-SchenectadyAlco-Schenectady
Year19291944
Valve GearBakerWalschaert
Locomotive Length and Weight
Driver Wheelbase19.25'19.75'
Engine Wheelbase45.58'47.08'
Ratio of driving wheelbase to overall engine wheebase 0.42 0.42
Overall Wheelbase (engine & tender)88'95.92'
Axle Loading (Maximum Weight per Axle)
Weight on Drivers265500 lbs280000 lbs
Engine Weight434000 lbs467000 lbs
Tender Light Weight304300 lbs370500 lbs
Total Engine and Tender Weight738300 lbs837500 lbs
Tender Water Capacity15000 gals21500 gals
Tender Fuel Capacity (oil/coal)20 tons5500 gals
Minimum weight of rail (calculated) on which locomotive could run111 lb/yard117 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter69"74"
Boiler Pressure250 psi270 psi
Cylinders (dia x stroke)26" x 32"26" x 32"
Tractive Effort66620 lbs67088 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.99 4.17
Heating Ability
Firebox Area505 sq. ft578 sq. ft
Grate Area88.30 sq. ft96.30 sq. ft
Evaporative Heating Surface5443 sq. ft4573 sq. ft
Superheating Surface2243 sq. ft1438 sq. ft
Combined Heating Surface7686 sq. ft6011 sq. ft
Evaporative Heating Surface/Cylinder Volume276.80232.56
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation2207526001
Same as above plus superheater percentage2847732241
Same as above but substitute firebox area for grate area162863193514
Power L14116434555
Power MT1367.251088.29

Photos

Reference

Credits

Introduction and roster provided by Richard Duley. Class details and specifications provided by Steve Llanso of Sweat House Media.