Union Railroad 0-10-2

Union Railroad 0-10-2
Type and origin Power type Steam Builder Baldwin Locomotive Works Serial number 61907–61911, 62059–62062, Build date 1936–1939 Total produced 10
Specifications Configuration: ​  • Whyte 0-10-2  • UIC E1′ Gauge 4 ft 8+1⁄2 in (1,435 mm) Driver dia. 61 in (1,549 mm) Adhesive weight 343,930 lb (156.0 tonnes) Loco weight 404,400 lb (183.4 tonnes) Total weight 644,510 lb (292.3 tonnes) Fuel type Coal Fuel capacity 28,000 lb (12.7 tonnes) Water cap. 12,000 US gal (45,000 L; 10,000 imp gal) Boiler pressure 260 lbf/in2 (1.79 MPa) Cylinders Two Cylinder size 28 in × 32 in (711 mm × 813 mm) Valve gear Walschaerts
Performance figures Tractive effort Loco: 90,900 lbf (404.3 kN), Tender booster: 17,150 lbf (76.29 kN)
Career Operators Union Railroad, Duluth, Missabe and Iron Range Class URR: ? DMIR: S7 Numbers URR 301-310; DM&IR 601-609 Retired URR: 1949, DM&IR: 1958–1963 Disposition One preserved, remainder scrapped

Ten Union Railroad 0-10-2 steam locomotives were built in 1936–1939 by the Baldwin Locomotive Works. These were the only 0-10-2 locomotives ever built in the United States and this purchase gave the name "Union" to this type.

The Union Railroad was a switching and transfer line owned by U.S. Steel, serving a number of plants in the area and connecting with six trunk line railroads. Operation was only at low speed, thus a leading truck's stability was not required. The intent was to eliminate helper requirements on grades, and thus a locomotive larger than the Union's previous switchers and 2-8-0 "Consolidations" was needed. Ten driving wheels allowed the application of sufficient tractive effort within the axle load limits of the line, and the requirement for a large firebox and plentiful steam-raising ability necessitated the trailing truck. To increase tractive effort still further, a booster engine was fitted to the leading tender truck. The unusual wheel arrangement was also a result of the turntable restrictions on the total wheel base.

Upon dieselization of the Union in 1949, nine of the locomotives were sold to fellow U.S. Steel railroad the Duluth, Missabe and Iron Range, where they served until 1962. One of these locomotives survives as a static exhibit at Greenville, Pennsylvania.