Ministerio de Viacao e Obras Publica 4-8-4 Locomotives in Brazil

Class Details by Steve Llanso of Sweat House Media

Class 730 (Locobase 21132)

Data from Baldwin Locomotive Works, Negative 13,157, 4-8-4 18 S 1 supplied by Teemu Koivumaki in a March 2023 email (Locobase thanks him). See also Jonas Augusto Martins de Carvalho, "As "gigantes" da Rede Mineira de Viatpo", posted 17 March 2012, on the Nucleo de Estudios de Oeste de Minas website at [], last accessed 3 April 2023. Works numbers were 72244-72253 in April 1946.

Orders for this particular metre-gauge design were awarded by Brazil's Ministerio de Viacao e Obras Publica to several builders to equip several railways.. Locobase 268, 20999, and 20324 show the Alco/Montreal Locomotive Works. The Eddystone products went to two different railways. Parana Santa Catarina received six (road 730-732 and 804-806) and Rede Minera de Viacao took four (road 600-603).

Baldwin's builders card shows the mix of traditional elements (such as the Type A superheater, cast-iron cylinders), 15 sq ft (1.39 sq m) of firebrick tubes and more recent innovations. The latter includes a combustion chamber contributing 68 sq ft (6.32 sq m) and thermic syphons 62 sq ft (5.76 sq m) to the direct heating surface area. Steam entered the cylinders through 10" (254 mm) piston valves.

Jonas Carvalho's NEOM post (translated by Google) describes an unusual source for this quartet (and likely for all others described in the other Locobase entries mentioned above. In Brazil, the end of World War II came as the Departamento Nacional de Estradas de Ferro (DNEF or National Railways Department) needed more modern motive power At the same time, the USA's sudden end to its plans to invade Japan in August 1945 made superfluous orders for several batches of narrow-gauge locomotives originally intended to support US operations on the mainland's 3 ft 6 in (1,067 mm) gauge railways after landing in Kyushu and later the Tokyo Plain.

Production of these locomotives hadn't actually begun and the small difference in gauge width (67 mm or 2.63") likely proved a minor detail change. What the Brazilians got, wrote Carvalho, were scaled down versions of North American 4-8-4s. On the RMV, however, these "Virginiams" (a puzzling nickname) were "giants". Indeed, the Brazilians at once "admired [them] for their grandeur and modern design and at the same time feared [them] for their 'giantness'."

Planned to haul limestone from Minas Gerais to Rio de Janeiro, the 600s encountered some ugly facts. According to Carvalho, "With the high price of imported coal and the low quality of national coal, combined with the railroad's cost containment, these locomotives began to work with a poor mix of national coal and firewood, thus drastically reducing their performance."

Moreover they struggled to negotiate some of the tight curves. Although Carvalho doesn't explicitly link "numerous" accidents to the mechanical stokers limiting the flexibility the engine-tender connection, he reports the "removal of the mechanically stokers from the furnaces [i.e. fireboxes]. Then the engines required the "hard work of two stokers."

Some of the difficulties were remedied in 1956-1957 when 600-602 were converted to oil-burning, "thus optimizing their peformance," wrote Carvalho. But that didn't solve the larger problem of the poor state of the permanent way.

Principal Dimensions by Steve Llanso of Sweat House Media

Locobase ID21132
RailroadMinisterio de Viacao e Obras Publica
Number in Class3
Road Numbers730-732
Number Built3
Valve GearBaker
Locomotive Length and Weight
Driver Wheelbase (ft / m)15.75 / 4.80
Engine Wheelbase (ft / m)37 / 11.28
Ratio of driving wheelbase to overall engine wheelbase 0.43
Overall Wheelbase (engine & tender) (ft / m)72.92 / 22.23
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)113,500 / 51,483
Engine Weight (lbs / kg)212,300 / 96,298
Tender Loaded Weight (lbs / kg)169,300 / 76,793
Total Engine and Tender Weight (lbs / kg)381,600 / 173,091
Tender Water Capacity (gals / ML)5300 / 20.08
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)22 / 20
Minimum weight of rail (calculated) (lb/yd / kg/m)47 / 23.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)59 / 1499
Boiler Pressure (psi / kPa)235 / 16.20
High Pressure Cylinders (dia x stroke) (in / mm)18" x 28" / 457x711
Tractive Effort (lbs / kg)30,714 / 13931.65
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.70
Heating Ability
Tubes (number - dia) (in / mm)112 - 2" / 51
Flues (number - dia) (in / mm)32 - 5.375" / 137
Flue/Tube length (ft / m)17 / 5.18
Firebox Area (sq ft / m2)312 / 28.99
Grate Area (sq ft / m2)56.30 / 5.23
Evaporative Heating Surface (sq ft / m2)2065 / 191.84
Superheating Surface (sq ft / m2)644 / 59.83
Combined Heating Surface (sq ft / m2)2709 / 251.67
Evaporative Heating Surface/Cylinder Volume250.40
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation13,231
Same as above plus superheater percentage16,406
Same as above but substitute firebox area for grate area90,917
Power L126,399
Power MT2051.09

All material Copyright ©
Wes Barris