NSB 4-8-0 Locomotives in Norway

Class Class 26a/b (Locobase 1737)

Data from "4-Cylinder Superheater Locomotive, Norwegian State Railways," Locomotive, XVII (15 February 1911), pp. 39-40. Svein Sando's Railway Site [] (9 June 2004)--(Later link: The Semaphore, accessed for link update 10 July 2022.)--and the Jernbane (Iron Road) site http://jernbane.net (June 2004); and "4-8-0 Four-Cylinder Goods Locomotives, Norwegian State Rys", Locomotive Magazine, Volume XXIII [23] (15 August 1917), pp. 152-154.

Norwegian Railway Club (Norsk Jerbaneklubb) website [] noted that this design was a response to the increased traffic on the Bergen line. SLM (Switzerland) delivered the first three as 26a and Thune of Norway added two a year later; the latter put 47,500 kg (104,719 lb) on the drivers.

W B Thompson wrote to Locomotive Magazine after the original article appeared in February 1911. His report, which appeared on pages 58-59 of the 15 March 1911 issue, said that these locomotives' driver diameter would normallyl consign them to the "slowest of slow mineral service." But he found that they seemed to "run quite satisfactorily and ...could keep up a steady 35 miles per hour (56 km/h) when running downhill without apparently knocking themselfes to pieces." He added that because all tourists on the line had to take the one passenger train a day and these engines, though bigger and heavier than previous locomotives, needed helper service.

Apparently not fully pleased with the fuel mileage of these 4-cylinder simples, NSB ordered the 26c after World War I. See Locobase 1738.

Class Class 26c (Locobase 1738)

Data from:

Svein Sando's Railway Site [] (9 June 2004)--(Later link: The Semaphore, accessed for link update 10 July 2022.)--and the Jernbane (Iron Road) site http://jernbane.net (June 2004)

Norwegian Railway Club (Norsk Jerbaneklubb) website [] . Four-cylinder compound variants of the basic Class 26 twelve-wheeler. The batch of 17 was delivered over five years by Hamar, Motala (Sweden), NOHAB (Sweden), SLM (Switzerland), and Thune.

Class Class 31a (Locobase 4078)

Data from Svein Sando's Railway Site [] (9 June 2004)--(Later link: The Semaphore, accessed for link update 10 July 2022.)--and the Jernbane (Iron Road) site http://jernbane.net (June 2004). See also "4-8-0 Four-Cylinder Goods Locomotives, Norwegian State Rys", Locomotive Magazine, Volume XXIII [23] (15 August 1917), pp. 152-154.

To cope with increased traffic on the Bergen line, Thune delivered an enlarged Class 26 twelve-wheeler. The Norwegian Railway Club (Norsk Jerbaneklubb) website [] notes that although a splendid sight to behold as it worked a freight train, these four-cylinder simples were fuel hogs.

See Class 31b (Locobase 4079) for the compound variant that was built in greater numbers.

Class Class 31b (Locobase 4079)

Data from:

Svein Sando's Railway Site [] (9 June 2004)--(Later link: The Semaphore, accessed for link update 10 July 2022.)--and the Jernbane (Iron Road) site http://jernbane.net (June 2004). See also D[ennis] Rock Carling, 4-8-0 Tender Engines (New York: Drake Publishers, Inc, 1972), pp. 34-36 and serial 69, Table VI [6], pp. 98-99.

When the Class 31a proved to have the power for the freight traffic demands, but too great an appetite for coal, the four-cylinder simple design was converted to a four-cylinder compound on the Woolf pattern. This variation paired an HP cylinder inside and above the corresponding outside LP cylinder. Each side's HP cylinder was fed live steam from its piston valve. Unlike most compounds, which used an intermediate receiver to manage the pressure, the Woolf design (which dated to the early 1800s) sent the HP cylinder's exhaust directly through a passage to enter into the same end of the LP cylinder just outside. The result was a gratifying reduction in fuel consumption.

The Norwegian Railway Club (Norsk Jerbaneklubb) website [] notes that NOHAB of Sweden delivered the first four and Breda of Italy supplied two more (which were regarded as "very successful units"). All of the rest were built in Norway by NMI (415-419, 426-429), Hamar & Thune (446-449, 452-453), and Thune alone (430-431).

The Norwegian Railway Museum website concludes: "All in all ...[these] turned out to be one of the most powerful and successful locomotive class ever in Norway." They were equal in power to the ex-German Class 52 2-10-0s brought to Norway under Nazi occupation. Only the famous Dovre Giants (Class 49) were more powerful.