4-4-0 Steam Locomotives in Germany

Class P4.1/BR 36.12 (Locobase 15130)

Data from 1896: Personenzuglokomotive, P 4.1 (2 B-PL), Baureihe 36.12 in Laenderbahn.info ( []). See also Albert Gieseler, "Baureihe 36.12" on his Dampmaschinen und Lokomotiven website at [], last accessed 29 September 2019.

Very similar to the Hanover P4.1s described in Locobase 5841 , the first five of the class arrived in 1896. They had no steam dome and only a small sand dome on the boiler. They proved very efficient for their size, managing 368 -tonne (405 short ton) trains on the level at speeds up to 42 mph (68 km/h).

Fourteen more arrived from Hanomag in1902. The whole class was gathered into the DRG as Bau Reihe 36.12. They only served a short while with the last being withdrawn in 1931.

Class P4.2 / BR 36.12 (Locobase 8962)

Data from Albert H Bone, "Some Recent Designs of Locomotives for Service on Continental Railways", Cassier's Magazine, 1910, pp. 561-609, supplemented and amended by [], last accessed 14 May 2011; and "Passenger Locomotive for the Duchy of Oldenburg Railroads", Railroad Gazette, Volume 43, No 3 (19 July 1907), pp. 73-74. Locomotive 178 bore Hannover works number was 5000. (Works numbers for the class were 4996-5000 in 1907, 548-5410 in 1909.

Bone concedes that there's nothing remarkable about this American-type Eight-wheeler, but he included it in the tabulation of recent designs for its Lentz valves, "...a form of double-seated valve, actuated by means of a reciprocating rod having hardened, cam-shaped surfaces which engage with hardened steel rollers mounted in the valve spindles." The valve was fitted to the 1909 trio (road numbers 188-190).

He observed that the Lentz valve would be a "formidable rival" to the slide valve and, while this did not happen, many locomotives would be so equipped. Bone summarized well the advantages of such cam-operated "drop valves" (Caprotti valves were another example) over slide valves: "Owing to their quick opening and closing, a better indicator diagram can be obtained, with an absence of wire-drawing." In the presence of highly superheated steam, "...they have the advantage of being without rubbing surfaces under pressure."

Although not described as a superheated engine, the design did have a Ranafier steam dryer fitted between the HP and LP cylinders that included 154 sq ft of heating surface.

Bone noted that these engines attained speeds of 68 km/h (42.25 mph) betweeen Wilhelmshaven and Oldenburg with a trailing load of 34 axles totalling 342 tons and 45-55 km/h (28-34 mph) trailing 425 tons.