Magyar Allamvasutak 4-4-4 Locomotives in Hungary


Class Details by Steve Llanso of Sweat House Media

Class 242 (Locobase 1549)

Data from Wikipedia at []; and A E Durrant The Steam Locomotives of Eastern Europe (Newton Abbot:David & Charles, 1966), pp 25, 40.

Medium-sized and powerful, these were unusual tank engines, wrote Durrant, in that they were fully streamlined. They were procured to meet a need for high-speed train service over relatively light track and to be able work equally efficiently in both directions. A larger firebox and grate burned relatively low-calorie coal that yielded a high ash content and required a rocking grate. The first two had steel fireboxes, but problems with corrosion led to the later two being delivered with copper fireboxes; Locobase cannot say if the first two had their fireboxes replaced. Because the engines covered just 155 miles (250 km) on a typical run, the designers felt able to do away with a separate tender.

The quartet satisfied the requirement handsomely. Trials included runs of up to 160 km/h (99 mph). They ran at 75 mph (120 km/h) on the Budapest-Miskolc line, proving themselves to be stable and smooth-riding.

Later they received a double-stacked Ister multiple-jet blastpipe. Nicknamed the "Coffins" because of their all-encompassing casings, the class remained in service until 1961.

Principal Dimensions by Steve Llanso of Sweat House Media

Class242
Locobase ID1549
RailroadMagyar Allamvasutak (MAV)
CountryHungary
Whyte4-4-4T
Number in Class4
Road Numbers242.001-242.004
GaugeStd
Number Built4
BuilderMAVAG
Year1936
Valve GearHeusinger
Locomotive Length and Weight
Driver Wheelbase (ft / m)
Engine Wheelbase (ft / m)34.71 / 10.58
Ratio of driving wheelbase to overall engine wheelbase
Overall Wheelbase (engine & tender) (ft / m)34.71 / 10.58
Axle Loading (Maximum Weight per Axle) (lbs / kg)32,187 / 14,600
Weight on Drivers (lbs / kg)64,375 / 29,200
Engine Weight (lbs / kg)188,275 / 85,400
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)188,275 / 85,400
Tender Water Capacity (gals / ML)2640 / 10
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) 5.40 / 5
Minimum weight of rail (calculated) (lb/yd / kg/m)54 / 27
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)78.70 / 1999
Boiler Pressure (psi / kPa)261.10 / 18
High Pressure Cylinders (dia x stroke) (in / mm)16.93" x 25.59" / 430x650
Tractive Effort (lbs / kg)20,684 / 9382.12
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.11
Heating Ability
Tubes (number - dia) (in / mm)
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)
Firebox Area (sq ft / m2)133.47 / 12.40
Grate Area (sq ft / m2)29.60 / 2.75
Evaporative Heating Surface (sq ft / m2)1673 / 155.43
Superheating Surface (sq ft / m2)379 / 35.21
Combined Heating Surface (sq ft / m2)2052 / 190.64
Evaporative Heating Surface/Cylinder Volume250.92
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation7729
Same as above plus superheater percentage9120
Same as above but substitute firebox area for grate area41,122
Power L129,542
Power MT2023.42

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