Imperial Government Railways 2-4-4-0 Locomotives in Japan

Class 9020/4600 (Locobase 20206)

Data from "American Locomotives in Japan", Locomotive Magazine, Volume XXIV, No. 3 (15 March 1918), p. 40; and "JGR Class 9020" in Locomotive Wiki at [], last accessed 13 January 2024.. Works numbers were 49829-49834 in March 1911.

Among the Mallet articulated locomotives eventually operated in Japan, ths sextet were among the first. They also rolled on a relatively unusual wheel arrangement that added a leading truck to a small Mallet articulated all-adhesion design. (Note: most sources show the engines as 0-4-4-0, but the Locomotive Wiki photograph clearly shows a leading truck. It's possible that the railway fitted the truck after early testing suggested the addition.)

Piston valves supplied live steam to the rear engine unit; slide valves sufficed for the low-pressure cylinders in the leading unit.

Whatever the IGR may have expected from these engines, they did not deliver a satsifactory result. All were discarded by 1925.