Merida a Peto, a Calkini, a Valladolid 4-4-0 Locomotives in Mexico

Class Details by Steve Llanso of Sweat House Media

Class Tecoh (Locobase 11790)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 10, p. 236; 11, p. 122. Works numbers were 6017 in January 1882, 6111 in March, 6478 in November, 7129 in January 1884

This Eight-wheeler quartet was bought by Ybarra & Company in Merida in the Yucatan to equip three different lines - The Tecoh belonged to the Merida a Peto, the Delfina O de Diaz to the Merida a Cakini, and the last two - Conkal and Merida - to the Merida a Valladolid. The lines were all brought together under the Unidos de Yucatan banner. The Delfina was sold to Glarra & Company from U de Y in 1906 and renamed Chocol'; it was later sold to Peninsular.

Principal Dimensions by Steve Llanso of Sweat House Media

Locobase ID11790
RailroadMerida a Peto, a Calkini, a Valladolid
Number in Class4
Road Numbers2 / 1 / 1- 2
Number Built4
BuilderBurnham, Parry, Williams & Co
Valve GearStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m) 7.17 / 2.19
Engine Wheelbase (ft / m)18.25 / 5.56
Ratio of driving wheelbase to overall engine wheelbase 0.39
Overall Wheelbase (engine & tender) (ft / m)
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)24,000 / 10,886
Engine Weight (lbs / kg)37,000 / 16,783
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)
Tender Water Capacity (gals / ML)1200 / 4.55
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)
Minimum weight of rail (calculated) (lb/yd / kg/m)20 / 10
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)45 / 1143
Boiler Pressure (psi / kPa)140 / 9.70
High Pressure Cylinders (dia x stroke) (in / mm)12" x 16" / 305x406
Tractive Effort (lbs / kg)6093 / 2763.74
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.94
Heating Ability
Tubes (number - dia) (in / mm)113 - 1.5" / 38
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m) 8.81 / 2.69
Firebox Area (sq ft / m2)52 / 4.83
Grate Area (sq ft / m2) 8.20 / 0.76
Evaporative Heating Surface (sq ft / m2)439 / 40.80
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)439 / 40.80
Evaporative Heating Surface/Cylinder Volume210.05
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation1148
Same as above plus superheater percentage1148
Same as above but substitute firebox area for grate area7280
Power L13512
Power MT645.22

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