Swiss Central 4-4-0 Locomotives in Switzerland


Class Details by Steve Llanso of Sweat House Media

Class 261 (Locobase 6790)

Data shown in the table presented on pages 367, 369 of the Groupe VI. - GTnie civil. - Moyens de transport. DeuxiFme partie. Classes 32 (Tome I), part of the series of Rapports du Jury Internationale of the Exposition Unverselle Internationale de 1900 Paris Exposition, hosted on the website of Le Conservatoire numTrique des Arts & MTtiers ([link], Accessed 21 August 2005).

According to the jury report, the requirements included pulling 240 tonnes up a 1% grade at 45 km/h (28 mph). See Locobase 2783 for the Series production locomotives, which were essentially identical.


Class unknown (Locobase 2783)

Data from Reder (1974, pl 251. Works numbers were 1046-1050 in 1897, 1146-1150 in 1898, 1286 in 1900.

Reder invited confusion when he commented that after the prototype was displayed at the 1900 Paris World Fair, it was bought by the Swiss Central "which then ordered another fourteen, Nos 251-256 (sic)."

These were De Glehn compounds, this design differed from the French variety in using Joy valve gear. The cranks were set at 180 deg in the first batch; the 1902 order set the cranks at 162 deg, which was the Nord's preference. Reder summarizes their career: "They were abandoned in favor of the less complicated two-cylinder construction because of their involved assembly and numerous components."


Class unknown (Locobase 15609)

Data from diagram No 98, Societe Alsacienne de Construction Mecaniques from SACM locomotive book supplied by Dany Machi up at [link] as

Diagrammes des machines SACM construites a GRAFENSTADEN (October 2007).

Principal Dimensions by Steve Llanso of Middle Run Media
Class261unknownunknown
Locobase ID6790 2783 15609
RailroadSwiss CentralSwiss CentralSwiss Central
CountrySwitzerlandSwitzerlandSwitzerland
Whyte4-4-04-4-04-4-0T
Number in Class110
Road Numbers261251-260
GaugeStdStdStd
Number Built110
BuilderSLMSLMSACM
Year19001897
Valve GearJoyJoyStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m) 8.50 / 2.59 8.50 / 2.59 8.37 / 2.55
Engine Wheelbase (ft / m)22.97 / 722.97 / 722.80 / 6.95
Ratio of driving wheelbase to overall engine wheelbase 0.37 0.37 0.37
Overall Wheelbase (engine & tender) (ft / m)22.80 / 6.95
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)66,139 / 30,00066,150 / 30,005
Engine Weight (lbs / kg)109,349 / 49,600108,045 / 49,008106,263 / 48,200
Tender Loaded Weight (lbs / kg)67,241 / 30,500
Total Engine and Tender Weight (lbs / kg)176,590 / 80,100106,263 / 48,200
Tender Water Capacity (gals / ML)1452 / 5.50
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) 4.40 / 4 2.20 / 2
Minimum weight of rail (calculated) (lb/yd / kg/m)55 / 27.5055 / 27.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)68.10 / 173068 / 172761 / 1550
Boiler Pressure (psi / kPa)203.10 / 1400210.30 / 1450169.70 / 1170
High Pressure Cylinders (dia x stroke) (in / mm)13" x 23.62" / 330x60013" x 23.62" / 330x60016.54" x 24.41" / 420x620
Low Pressure Cylinders (dia x stroke) (in / mm)20.08" x 23.62" / 510x60020" x 23.62" / 508x600
Tractive Effort (lbs / kg)14,261 / 6468.6914,753 / 6691.8615,791 / 7162.69
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.64 4.48
Heating Ability
Tubes (number - dia) (in / mm)224 - 1.77" / 45182 - 1.811" / 46
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)12.47 / 3.8011.71 / 3.57
Firebox Area (sq ft / m2)111.90 / 10.4088.80 / 8.25
Grate Area (sq ft / m2)23.67 / 2.2023.70 / 2.2017.22 / 1.60
Evaporative Heating Surface (sq ft / m2)1404 / 130.481392 / 129.371109 / 103
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1404 / 130.481392 / 129.371109 / 103
Evaporative Heating Surface/Cylinder Volume386.92383.62182.69
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation480749842922
Same as above plus superheater percentage480749842922
Same as above but substitute firebox area for grate area22,72715,069
Power L152284414
Power MT348.53

All material Copyright © SteamLocomotive.com
Wes Barris