All twenty-five of these Class N-78s were coal fired and had 63" diameter drivers, 30" x 32" cylinders, a 200 psi boiler pressure, they exerted 77,715 pounds of tractive effort and each weighed 385,400 pounds. Their firebox had 116.7 square feet of thermic syphons.
In 1925, another group of ALCO-built "Santa Fes" was added to the roster. These locomotives were oil-fired and were also classified as Class N-78. They had 63" diameter drivers, 30" x 32" cylinders, a 200 psi boiler pressure, they exerted 77,715 pounds of tractive effort and each weighed 405,000 pounds. The firebox had 121 sq ft of thermic syphons and some of the boilers had feedwater heater,
All thirty-five of the CRIP's "Santa Fes" as delivered had counterbalancing problems and were limited to 30 mph. Refitting them with disk drivers reduced the problem and reducing the pounding.
There are no surviving CRIP 2-10-2 "Santa Fe" type locomotives.
|Class||Qty.||Road Numbers||Year Built||Builder||Notes|
|N-78||10||3001-3010||1918||ALCO||Numbers 3001-3010 scrapped between 1939 and 1952.|
|N-78||15||3011-3025||1920||ALCO||Numbers 3011-3025 scrapped between 1939 and 1952.|
|N-78||10||3026-3035||1925||ALCO||Numbers 3026-3035 scrapped between 1939 and 1952.|
Data from "Rock Island 2-10-2 Locomotive", Railway Mechanical Engineer, Volume 93, No 1 (January 1919), pp. 41-43; and "Mikado, Santa Fe, and Mountain Type Locomotives for the Chicago, Rock Island and Pacific Railway", Railway and Locomotive Engineering, Volume 34, No 2 (February 1921), pp. 33-35. (Thanks to Chris Hohl for his 6 October 2017 email noting the original specifications and pointing Locobase to the 1919 journal report that supllied the correct data.) Brooks produced the locomotives in two batches -- 3001-3010 (works numbers were 58305-58314 in May 19181918 locomotives were delivered with combustion chambers and arch tubes, the latter contributed 36 sq ft (3.35 sq m) to the direct heating surface area. The 1920 locomotives incorporated 141 sq ft () of Nicholson thermic syphons; see Locobase 7234. Fourteen-inch (381 mm) piston valves actuated by outside radial valve gear admitted steam to the cylinders. Drury's (1993) assessment: "Even with 63" drivers, [they] had counterbalancing problems and were limited to 30 mph." Not long after they entered service, the class's boiler pressure was increased to 200 psi (13.8 bar). Later refitting with disk drivers ameliorated the pounding and more direct heating surface and a stil higher boiler pressure increased power even more.
Data from 1930 Locomotive Cyclopedia, supplemented by RI to 1951 Combined Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. (Many thanks to Chris Hohl for his 22 September 2017 email reporting unlikely boiler pressure values for 177 entries. A Locobase macro caused the error .)These were the last ten of the 35 Santa Fes delivered to the Rock Island and manifested an increase in superheater area; and tubes and flues were 1 ft 10" (559 mm) longer than those of the first group described in Locobases 16315 and 7234. The firebox had 121 sq ft (11.24 sq m) of thermic syphons and some of the boilers had feedwater heaters (Four had Worthington BLs and three had Elescos). Three more had exhaust steam injectors. Fourteen-inch (381 mm) piston valves supplied steam to the cylinders. Later refitting with disk drivers ameliorated the pounding endemic to all North American 2-10-2s.
Data from RI1 -1942 and RI to 1951 Combined Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also "Mikado, Santa Fe, and Mountain Type Locomotives for the Chicago, Rock Island and Pacific Railway", Railway and Locomotive Engineering, Volume 34, No 2 (February 1921), pp. 33-35. (Thanks to Chris Hohl for his 28 October 2019 email noting the original boiler pressure, as well as tender weight and capacity.) Works numbers were 62162-62176 in October 1920.Locobase 16315 shows the original set of ten Santa Fes as they arrived on the Rock Island in 1918. That batch's supplemental firebox heating surface amounted to the combustion chamber and arch tubes. The 1920 locomotives arrived fitted with 141 sq ft (10.85 sq m) of thermic syphons in place of the original arch tubes. One of the syphons was later removed, reducing syphon area to 116.7 sq ft (10.84 sq m) and firebox heating surface area to 458.2 sq ft (42.57 sq m). This batch retained the 14" (356 mm) piston valves and 185 psi operating pressure. Drury's (1993) assessment that "Even with 63" drivers, [they] had counterbalancing problems and were limited to 30 mph." led to refitting with disk drivers that ameliorated the pounding and allowed a permissible speed of 50 mph (81 kph). By 1942, the Rock Island had raised boiler pressure to 215 psi (14.8 bar), increasing tractive effort to 83,453 lb (37,895 kg or 371.6 kN) while reducing minimum factor of adhesion to 3.69. Chris Hohl pointed out that when these were delivered as coal burners, their loaded tenders weighted 192,500 lb and carried 16 tons of coal (14.55 metric tons). When converted to oil burning, tender water capacity remained the same; the largest-capacity oil tender used by the Rock Island's 2-10-2s is shown in the Locobase specs. Those retained as coal burners eventually trailed the heaviest tenders, which weighed 241,000 lb (109,316 kg) when carrying 14,000 US gallons (52,990 litres) of water and 18 tons (16.4 metric tons) of coal and brought the full power system weight of engine and tender to 632,000 lb (286,670 kg).
|Principal Dimensions by Steve Llanso of Sweat House Media|
|Railroad||Chicago, Rock Island & Pacific (CRI&P)||Chicago, Rock Island & Pacific (CRI&P)||Chicago, Rock Island & Pacific (CRI&P)|
|Number in Class||10||10||15|
|Locomotive Length and Weight|
|Driver Wheelbase (ft / m)||22.50 / 6.86||22.50 / 6.86||22.50 / 6.86|
|Engine Wheelbase (ft / m)||41.25 / 12.57||42.58 / 12.98||41.25 / 12.57|
|Ratio of driving wheelbase to overall engine wheelbase||0.55||0.53||0.55|
|Overall Wheelbase (engine & tender) (ft / m)||80.23 / 24.45||82.67 / 25.20||80.23 / 24.45|
|Axle Loading (Maximum Weight per Axle) (lbs / kg)|
|Weight on Drivers (lbs / kg)||302,500 / 137,212||317,500 / 144,016||308,500 / 139,933|
|Engine Weight (lbs / kg)||383,000 / 173,726||405,000 / 183,705||391,000 / 177,355|
|Tender Loaded Weight (lbs / kg)||189,900 / 86,137||223,600 / 101,423||207,100 / 93,939|
|Total Engine and Tender Weight (lbs / kg)||572,900 / 259,863||628,600 / 285,128||598,100 / 271,294|
|Tender Water Capacity (gals / ML)||10,000 / 37.88||12,000 / 45.45||10,000 / 37.88|
|Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)||16 / 15||18 / 16||4550 / 17,222|
|Minimum weight of rail (calculated) (lb/yd / kg/m)||101 / 50.50||106 / 53||103 / 51.50|
|Geometry Relating to Tractive Effort|
|Driver Diameter (in / mm)||63 / 1600||63 / 1600||63 / 1600|
|Boiler Pressure (psi / kPa)||185 / 12.80||215 / 14.80||215 / 14.80|
|High Pressure Cylinders (dia x stroke) (in / mm)||30" x 32" / 762x813||30" x 32" / 762x813||30" x 32" / 762x813|
|Tractive Effort (lbs / kg)||71,886 / 32606.98||83,543 / 37894.51||83,543 / 37894.51|
|Factor of Adhesion (Weight on Drivers/Tractive Effort)||4.21||3.80||3.69|
|Tubes (number - dia) (in / mm)||226 - 2.25" / 57||210 - 2.25" / 57||226 - 2.25" / 57|
|Flues (number - dia) (in / mm)||46 - 5.5" / 140||50 - 5.5" / 140||46 - 5.5" / 140|
|Flue/Tube length (ft / m)||21.25 / 6.48||23.08 / 7.03||21.25 / 6.48|
|Firebox Area (sq ft / m2)||391 / 36.32||445 / 41.34||532 / 49.42|
|Grate Area (sq ft / m2)||80.20 / 7.45||80.30 / 7.46||80.20 / 7.45|
|Evaporative Heating Surface (sq ft / m2)||4608 / 428.09||4940 / 458.94||4692 / 436.06|
|Superheating Surface (sq ft / m2)||1180 / 109.62||1375 / 127.74||1197 / 111.25|
|Combined Heating Surface (sq ft / m2)||5788 / 537.71||6315 / 586.68||5889 / 547.31|
|Evaporative Heating Surface/Cylinder Volume||176.01||188.69||179.22|
|Computations Relating to Power Output (More Information)|
|Robert LeMassena's Power Computation||14,837||17,265||17,243|
|Same as above plus superheater percentage||17,804||21,063||20,692|
|Same as above but substitute firebox area for grate area||86,802||116,724||137,256|