| Chicago Burlington & Quincy Railroad 2-6-2 Class R-4 1950 presumed at Dunkirk, New York sometime in January 1905, photograph by the Brooks Locomotive Works, Chuck Zeiler collection. The Brooks Works (which became part of the American Locomotive Company in 1901) built 50 class R-4 2-6-2's for the CB&Q during 1905, numbered 1940-1989. They were of a similar design as the Baldwin-built R-4's completed in 1904 (#'s 1900-1939), and an additional 50 were built by Baldwin during 1906 (#'s 2000-2049) The total engine weight of the R-4 Prairies was 208,550 pounds, their operating steam pressure was 210 psi, and they exerted a tractive force of 35,000 pounds. The boilers were of the straight-top design, but in place of the Belpaire-type firebox used on the preceding classes, ones of radial-stay construction were used. The 12 inch piston-type valves were of the inboard type and were actuated by Stephenson link motion. The cylinder arrangement was similar to the P-2 Atlantics. Although the piston rods were extended forward of the cylinders (for additional bearing support) on the first Baldwin-built class R-4 engines, this was later modified and the extended portion was removed. Some of the R-4 locomotives had 22 inch by 28 inch cylinders, and others were equipped with cylinders of 25 inch bore. The operating steam pressure was reduced to compensate for the increase in cylinder diameter. By the end of 1925, 14 of the R-4 Prairies were rebuilt with new cylinders of 25 inch by 28 inch and Walschaerts valve gear was applied to them. These engines were re-classed R-4A. A number of R-4 locomotives were rebuilt to G-10 switchers. The locomotive pictured was rebuilt to G-10 number 560 during December 1928, retired and sold for scrap in November 1953. During World War II when the Southern Pacific Railroad became short of motive power, several of the R-4 engines were leased by that road and sent to the West Coast where they performed yard and branch line duties. |