American 4-6-0 Locomotives in USA-Puerto_Rico

Class 67 (Locobase 14182)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 49, p. 85. Works number was 39032 in January 1913.

Locobase 13032 describes the class of cross-compound Consolidations supplied to the American in 1907 and 10989 discusses the six Eight-wheelers of the same design but slightly less cylinder volume. The two designs converged in this single Ten-wheeler, whose minor details were to be the same as for the Eight-wheelers. Its size fell roughly halfway between the two other classes, its cylinder volume was the same as the Consolidation except for the driver diameter, which matched that of the 4-4-0s.

Class 68 (Locobase 14768)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Vol 63, p. 272. Works numbers were 50880-50883 in December 1918.

The ARR of PR ordered these superheated Ten-wheelers at the end of November 1917, but such was the pace of production at Eddystone that the quartet didn't emerge from the builder for more than a year. They built on the single compound that Baldwin delivered to the ARR in 1912 (Locobase 14182), adding a superheater and resorting to simple expansion. The higher temperatures of the superheater dictated substitution of 8" (203 mm) piston valves for steam admission.

Class 72 (Locobase 15418)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Vol 79, p. 46+. Works number was 60183 in September 1927.

Locobase 14768 shows the first four superheated Ten-wheelers delivered to the ARR in early 1919. When the railway wanted to add a fifth, they specified a duplicate. One anomaly was the drop in reported empty weight by more than three tons.

At the time, the railroad had average grades of 1.6% and a max grade of 2 1/2% and curve radii as tight as 262 feet (80 metres) or 21.9 degrees on 40 and 60 lb/yard (20 and 30 kg/metre) rail.