FC Central Norte Argentino 2-4-6-0 Locomotives in Argentina

Class 87 (Locobase 20811)

Data from "'Compound Articulated Locomotives (Metre Gauge) for the Central Northern Railway of the Argentine Republic", Engineering, Volume 82, No, (4 August 1905), pp. , 159-160.

This rare wheel arrangement appears on Locobase 10653, which describes Henschel's batch supplied to the Hejaz Railway. Compared to that Cape Gauge design, the CNs rolled on an even narrower gauge, but had larger boilers and weighed more. Locobases 13781 and 3742 mention the "quebracho" wood native to the area of northern Argentina within which the CCNA operated. (One observer translated the wood's name as "ax-breaker"). Engineering's report described the quebracho fuel as representing "the highest class of wood fuel".

On a road that permitted only an 8 ton (9 short tons) axle loading and offered challenging 1 in 40 (2 1/2 %) grades, the CCNA ordered two essentially identical designs from the Tegel builder. (Locobase 20812 covers the six-coupled, all-adhesion variant.); both had "liberal" grate and boiler proportions to allow the use of less-potent fuel. Placing the dome at the center of the boiler reduced the impact of water level shifts due to grade changes. Although the boiler was unsually high for the gauge and the times, the railway found that "such a height is not only permissible, but even, in conjunction with the great length of wheel base, conducive to steady running."

Both used the same Belpaire firebox layout, but the 87 had a more grate and firebox area. Engineering explained that the firebox "considerably inclined" toward the front "...so as to get as great a depth of fire as possible below the tube-plate."

The 87's role was to haul 120 tons of passenger train up the ruling grade at 16 mph (26 kph). Higher operating speeds dictated the provision of a leading truck, a two-axle front engine set, and taller drivers.