Societe Miniere et Metallurgique de Pe'arroya 2-8-2 Locomotives in Spain

Class Details by Steve Llanso of Sweat House Media

Class Porvenir (Locobase 14652)

Data from DeGolyer, Vol 60, pp. 331. Works number was 44341 in October 1916.

"Locomotive to have sufficient water capacity for a run of 30 kilometres [18.6 miles] without refilling the tanks, also sufficient fuel capacity for the same run." This specification demonstrates on just how short a tether steam engines operated. Once the boiler was steamed up, it used up both water and fuel continuously at some minimum rate until the fire was dropped. And there was no benefit to letting the water run low so a reserve in the tank was always necessary.

In this case, the fuel load consisted of dry soft coal with a long flame, 40% of cinders, 30% volatile matter.

The spec also gives details on the expectations: Locomotive to haul 250 metric tons [276 short tons][exclusive of engine] under most unfavorable conditions." Some of these stringencies included a 3% grade, combined with curves of 200 metres (656 feet) radius, that continued for 1.86 miles (3 km) that the engine had manage at a speed of 12 km/h (7.5 mph). On the level, the same load was to be drawn at 25 km/h (15.5 mph). Rail weight was 65 1/2 lb/yard (32.75 kg/metre).

Principal Dimensions by Steve Llanso of Sweat House Media

Locobase ID14652
RailroadSociete Miniere et Metallurgique de Pe'arroya
Number in Class1
Road Numbers9
Number Built1
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m)11.50 / 3.51
Engine Wheelbase (ft / m)26.50 / 8.08
Ratio of driving wheelbase to overall engine wheelbase 0.43
Overall Wheelbase (engine & tender) (ft / m)26.50 / 8.08
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)120,000 / 54,431
Engine Weight (lbs / kg)158,000 / 71,668
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)158,000 / 71,668
Tender Water Capacity (gals / ML)2000 / 7.58
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)3 / 3
Minimum weight of rail (calculated) (lb/yd / kg/m)50 / 25
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)43 / 1092
Boiler Pressure (psi / kPa)170 / 11.70
High Pressure Cylinders (dia x stroke) (in / mm)19" x 22" / 483x559
Tractive Effort (lbs / kg)26,689 / 12105.94
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.50
Heating Ability
Tubes (number - dia) (in / mm)216 - 2" / 51
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)12 / 3.66
Firebox Area (sq ft / m2)116 / 10.78
Grate Area (sq ft / m2)27.60 / 2.56
Evaporative Heating Surface (sq ft / m2)1464 / 136.01
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1464 / 136.01
Evaporative Heating Surface/Cylinder Volume202.78
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation4692
Same as above plus superheater percentage4692
Same as above but substitute firebox area for grate area19,720
Power L13449
Power MT253.46

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