Hollandsche Ijzeren Spoorweg Maatschappij 4-4-4 Locomotives in Netherlands

Class 806 (Locobase 14911)

Data from J J G Koopmans proposal to build a replica of the HSB 800 class dated July 2012 and found at [] . Works numbers were 378-384 in 1914-1915.

Koopsman traces the lineage of the 800s as an enlargement of the 771 series 4-4-2Ts, themselves the superheated makeovers of earlier 4-4-2T. He points out that the boiler wasn't interchangeable with the HSM 350-408. Its firebox was "almost the same firebox" as that used by the 601 and 671 0-6-0s and several 4-4-0 classes. Its layout featured bogies of equal length, which were spaced almost equally ahead and behind the driving axles.

The boiler also included a Knoor preheater that had a 9.2 sq metre (99 sq ft) area. The cylinders were supplied through piston valves.

They pulled commuter trains on the lines from Amsterdam to Enkhuizen, Haarlem and Hilversum. Once the rail lines were electrified immediately after World War II, the class, now NS 5800s, was retired between 1945 and 1951.

Koopsman argues for the reproduction of the 800 as a representative of "the large series of tank locomotives that the Netherlands has known and have given their proven service in the commuter traffic." He supplements that argument with the note that the class was designed by Werkspoor.