Data from Hiroshi Takagi, both from his website ([]) and personal communication August 2000. His indispensable assistance is gratefully acknowledged. See also A Profile of Japanese Steam Locomotives website put up in 2007 by "Toki S." at [
], last accessed 26 September 2015.
The C60s successfully spread engine weight over one more axle than the C59s from which they were derived. The first engine to be converted was the C59-27 in November 1953 at Hamamatsu Works. It was followed by sixteen more in 1953-1954. Clearly, the conversion satisfied the JNR as it converted 30 more engines in 1960. All but C60 18-22 were converted by Hamamatsu; the others were modified by Koriyama shops.
Electricfication of the Tohoku line led to the first C60 retirements in 1966. The last to retire went in October 1970.
Information from Ejii Nozawa's web site ([]) shows that C60s were rebuilt from C59s from 1953-1961 at JNR's Hamamatsu and Kouriyama Works. Nozawa gives a total heating surface of 241.3 sq meters, which converts to 2,596 sq ft. He doesn't break the figure down to EHS and SHS and Takagi's table does not have the C60
Because the measurements above represent the fire side of tubes and flues, a direct comparison with tube & flue heating surface areas of North American and British locomotives requires adding approximately 6-10% to the figures shown.
Data from Hiroshi Takagi, both from his website ([]) and personal communication August 2000. See also A Profile of Japanese Steam Locomotives website put up in 2007 by "Toki S." at [
], last accessed 27 September 2015.
Takagi's tables showed that this boiler had a large combustion chamber. He gave two values 1000 mm (39.4") and 920 mm (36.2"), but there's no additional explanation for the two values. (See Locobase 3841 for a short discussion of combustion chambers in Japanese locomotives.)
These were extensive rebuilds of D52 Mikados of pre-World War II construction. The Wikipedia entry on 4-6-4 ([]) comments on the question of this rebuild: "All were officially rebuilt from earlier locomotives of different arrangement, but it is believed that this was for accounting purposes rather than any real cost saving; the parts re-used appear to have been minimal."
The result was a set of Tsubame ("Swallows") that were highly satisfactory express engines. Piston valves measured a relatively generous 280 mm .
Hitachi, Kawasaki, and Kisha Seizo Kaisha were companies involved in the makeover. For years, C62s headed up crack trains in Japan such as the Hatsukari. Later they moved to Hokkaido as motive power for the Hakodate-Sapporo expresses.
One of the C62s set the speed record for narrow-gauge steam at 127 km/h (79 mph).
Information from Ejii Nozawa's web site ([]) notes that C62s were rebuilt from 1948-1949 by Hitachi, Kawasaki, and KSK.
Because the measurements above represent the fire side of tubes and flues, a direct comparison with tube & flue heating surface areas of North American and British locomotives requires adding approximately 6-10% to the figures shown.
Principal Dimensions by Steve Llanso of Middle Run Media | ||
---|---|---|
Class | C60 | C62 |
Locobase ID | 3837 | 2602 |
Railroad | Japanese National Railways (JNR) | Japanese National Railways (JNR) |
Country | Japan | Japan |
Whyte | 4-6-4 | 4-6-4 |
Number in Class | 47 | 49 |
Road Numbers | C60 1 - C60 47 | |
Gauge | 3'6" | 3'6" |
Number Built | 47 | 49 |
Builder | several | several |
Year | 1953 | 1949 |
Valve Gear | Walschaert | Walschaert |
Locomotive Length and Weight | ||
Driver Wheelbase (ft / m) | 10.83 / 3.30 | 12.47 / 3.80 |
Engine Wheelbase (ft / m) | 34.48 / 10.51 | 34.51 / 10.52 |
Ratio of driving wheelbase to overall engine wheelbase | 0.31 | 0.36 |
Overall Wheelbase (engine & tender) (ft / m) | 61.47 / 18.73 | 62.34 / 19 |
Axle Loading (Maximum Weight per Axle) (lbs / kg) | 33,069 / 15,000 | 35,450 / 16,080 |
Weight on Drivers (lbs / kg) | 98,679 / 44,760 | 106,329 / 48,230 |
Engine Weight (lbs / kg) | 182,763 / 82,900 | 195,836 / 88,830 |
Tender Loaded Weight (lbs / kg) | 134,702 / 61,100 | 121,651 / 55,180 |
Total Engine and Tender Weight (lbs / kg) | 317,465 / 144,000 | 317,487 / 144,010 |
Tender Water Capacity (gals / ML) | 2059 / 7.80 | 5821 / 22.05 |
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 11 / 10 | |
Minimum weight of rail (calculated) (lb/yd / kg/m) | 55 / 27.50 | 59 / 29.50 |
Geometry Relating to Tractive Effort | ||
Driver Diameter (in / mm) | 68.90 / 1750 | 68.90 / 1750 |
Boiler Pressure (psi / kPa) | 227.70 / 1570 | 227.70 / 1570 |
High Pressure Cylinders (dia x stroke) (in / mm) | 20.47" x 25.98" / 520x660 | 20.47" x 25.98" / 520x660 |
Tractive Effort (lbs / kg) | 30,580 / 13870.87 | 30,580 / 13870.87 |
Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.23 | 3.48 |
Heating Ability | ||
Tubes (number - dia) (in / mm) | 52 - 2.008" / 51 | 94 - 2.008" / 51 |
Flues (number - dia) (in / mm) | 33 - 5.157" / 131 | 35 - 5.157" / 131 |
Flue/Tube length (ft / m) | 18.01 / 5.49 | 16.40 / 5 |
Firebox Area (sq ft / m2) | 175.45 / 16.30 | 216.36 / 20.10 |
Grate Area (sq ft / m2) | 35.20 / 3.27 | 41.44 / 3.85 |
Evaporative Heating Surface (sq ft / m2) | 1473 / 136.80 | 1803 / 167.50 |
Superheating Surface (sq ft / m2) | 871 / 80.90 | 833 / 77.40 |
Combined Heating Surface (sq ft / m2) | 2344 / 217.70 | 2636 / 244.90 |
Evaporative Heating Surface/Cylinder Volume | 148.85 | 182.20 |
Computations Relating to Power Output (More Information) | ||
Robert LeMassena's Power Computation | 8015 | 9436 |
Same as above plus superheater percentage | 10,981 | 12,455 |
Same as above but substitute firebox area for grate area | 54,731 | 65,030 |
Power L1 | 26,923 | 27,432 |
Power MT | 1804.49 | 1706.32 |