Baltimore and Ohio Class N-1 Duplex 4-4-4-4 Steam Locomotive
The Baltimore and Ohio Railroad's sole Class N-1 steam locomotive, No. 5600 George H. Emerson, was the first duplex locomotive and the first 4-4-4-4 locomotive ever built. It was designed and built by the railroad's own shops in 1937. The rear set of cylinders were placed beside the firebox. This allowed the locomotive's wheelbase to remain the same. The space beside the firebox was hot and dirty, which caused premature cylinder wear, and the placement of the cylinders limited the size of the firebox. These same problems occurred on the PRR Q1, which also placed the rear cylinders by the firebox.
Baltimore and Ohio Railroad No. 5600 Overview
Type and origin
Power type: Steam
Builder: B&O Mount Clare Shops
Build date: May 1937
Total produced: 1
UIC class: 2′BB2′
Gauge: 4 ft 8 1⁄2 in (1,435 mm) standard gauge
Leading diameter: 36 in (914 mm)
Driver diameter: 76 in (1,930 mm)
Trailing diameter: 42 in (1,067 mm)
Minimum curve: 13° or 441.68 ft (134.62 m) normal, 18° or 319.62 ft (97.42 m) slow
Length: 117 ft 0 1⁄4 in (35.67 m)
Adhesive weight: 238,000 lb (108,000 kilograms; 108 metric tons)
Locomotive weight: 386,500 lb (175,300 kilograms; 175.3 metric tons)
Tender weight: 350,000 lb (160,000 kilograms; 160 metric tons)
Total weight: 736,500 lb (334,100 kilograms; 334.1 metric tons)
Tender type: Vanderbilt with two 3-axle trucks
Fuel type: Coal
Fuel capacity: 46,000 lb (21,000 kilograms; 21 metric tons)
Water capacity: 22,000 US gal (83,000 l; 18,000 imp gal)
• Firegrate area: 80.5 sq ft (7.48 m2)
Boiler pressure: 350 lbf/in2 (2.41 MPa)
Heating surface: 4,897 sq ft (454.9 m2)
• Tubes and flues: 4,220 sq ft (392 m2)
• Firebox: 677 sq ft (62.9 m2)
• Type: B&O
• Heating area: 1,312 sq ft (121.9 m2)
Cylinders: Four, duplex
Cylinder size: 18 in × 26.5 in (457 mm × 673 mm)
Valve gear: Walschaerts
Power output: 3,936 hp (2,935 kW) at cylinders
Tractive effort: 65,000 lbf (289.1 kN)
Factor of adhesion: 3.66
Operator: Baltimore and Ohio Railroad
Official name: George H. Emerson
Disposition: Scrapped, October 1950
B & O 5600 at the 1939 New York World's Fair. Library of Congress.
Detail, showing the rearward cylinders and gear. Library of Congress.
Baltimore and Ohio Railroad duplex locomotive, class N-1 No. 5600 George H. Emerson, at the 1939 New York World's Fair.
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Text: wikipedia.org. Images: Public Domain; http://www.commons.wikimedia.org (unless otherwise specified) and 17 U.S. Code § 107 fair use. References: Lewis, Robert G. The Handbook of American Railroads. New York: Simmons-Boardman Publishing Corporation, 1951, 2nd Edition 1956. Site Map Contact webmaster HERE.
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