Baltimore and Ohio 4500

Baltimore and Ohio 4500
B&O 4500 as it was built in 1918
Type and origin Power type Steam Builder Baldwin Locomotive Works Serial number 49153 Build date July 4, 1918
Specifications Configuration: ​  • Whyte 2-8-2  • UIC 1′D2′ h1 Gauge 4 ft 8+1⁄2 in (1,435 mm) standard gauge Leading dia. 33 in (838 mm) Driver dia. 63 in (1,600 mm) Trailing dia. 43 in (1,092 mm) Wheelbase Loco & tender: 41.98 ft (12.80 m) Axle load 55,200 lb (25,000 kilograms; 25.0 metric tons) Adhesive weight 220,000 lb (100,000 kilograms; 100 metric tons) Loco weight 292,000 lb (132,000 kilograms; 132 metric tons) Tender weight 185,400 lb (84,100 kilograms; 84.1 metric tons) Total weight 477,400 lb (216,500 kilograms; 216.5 metric tons) Fuel type Coal Fuel capacity 16 t (16 long tons; 18 short tons) Water cap. 10,000 US gal (38,000 L; 8,300 imp gal) Firebox: ​  • Grate area 66.70 sq ft (6.197 m2) Boiler pressure 200 lbf/in2 (1.38 MPa) Heating surface: ​  • Firebox 286 sq ft (26.6 m2) Superheater: ​  • Heating area 882 sq ft (81.9 m2) Cylinders Two Cylinder size 26 in × 30 in (660 mm × 762 mm) Valve gear Walschaert
Performance figures Tractive effort 53,800 lbf (239.31 kN) Factor of adh. 4.08
Career Operators Baltimore and Ohio Class Q-3 Number in class 1st of 100 Numbers B&O 4500 B&O 300 (from 1957-1964) Retired August 1957 Disposition On display at the B&O Railroad Museum in Baltimore, Maryland

Baltimore and Ohio 4500 is a 2-8-2 "USRA Light Mikado" steam locomotive built by the Baldwin Locomotive Works in Philadelphia, Pennsylvania in July 1918 for the Baltimore and Ohio Railroad (B&O) as a member of the Q-3 class.

The locomotive hauled freight for the B&O until retirement in August 1957 and was donated for display at the B&O Railroad Museum in Baltimore, Maryland. It is the sole surviving Baltimore and Ohio Mikado type steam locomotive.

History

The locomotive was the very first USRA locomotive built and it was constructed in. It was also finished on July 4th, 1918 and it was decked out with American Flags for the occasion. While is remained as built mechanically, it received some of B&O's distinctive cosmetic changes throughout its service life, but the locomotive retains the original tender and trailing truck. During its service life, the locomotive was in freight service primarily on the Ohio and St. Louis divisions of the railroad. In 1957, the locomotive was renumbered 300 to make room for four-digit diesel locomotives.

Preservation

In August 1957, 4500, still numbered 300, was retired and in 1964, it was put on display at the B&O Railroad Museum in Baltimore, Maryland and was renumbered back to 4500, its original number. In 1990, the locomotive was designated as a National Historic Mechanical Engineering Landmark. Today, it still resides there on display.