OKm11
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629.01 from the Südbahn fleet (StEG
3883/1913) has been preserved at the Heizhaus Strasshof, Austria; photo taken on June
20, 2009.
Late
production 354.1207, ČSD (Škoda 858/1937), location and date unknown (obviously
after the war!). Postcard from my collection.
Two more 354.1s on postcards from my collection:
354.1160 (Škoda 628/1930), still in service, Kraliky,
June 18, 1977…
…and 354.195 (PČM 1055/1925), photographed near Vižina
on September 18, 2004, with a special train.
Former BBÖ 629.43, later ÖBB 77.28, Krauss Linz 1183/1920, photographed in
Gmunden on May 1, 2008. Photo by Ernst Wolf (from
my collection).
77.250, ÖBB (pre-war 629.65, Krauss Linz
1430/1927), Wien Ost station, August 17, 1986. This
locomotive later ran in Liechtenstein with special trains. Photo from my
collection.
629.01, Südbahn, StEG 3883/1913,
photographed at the Heizhaus Strasshof
on April 30, 2000. Photo by Herbert Orther (www.commons.wikimedia.org).
Side drawing of the OKm11 by Marek Ćwikła (source: SK
vol. 6/2020). |
The
2-3-1 axle arrangement, known as Pacific, was very popular in Europe
and chosen by many companies for fast, if not very heavy, express
locomotives. The most popular record-breaking streamlined engines, A4
‘Mallard’ (LNER) and 03 001 (DRG), were Pacifics;
so was Polish Pm36, perhaps the best known PKP steam locomotive.
Austrian railways were a notable exception: their only Pacific was class 629,
a tank engine intended for passenger and light express traffic. Class
629 was conceived as a successor to earlier class 229 (1-3-1 axle
arrangement, PKP class OKl12) and, after some discussion concerning
axle loads, two-axle lead truck was introduced. This was in fact intended not
to improve running qualities, but rather to avoid excessive front axle load
with longer and heavier boiler. Another important modification was
introduction of steam superheating and single-expansion engine. First fifteen
engines of this type were ordered by Südbahn,
delivered between 1913 and 1915 and numbered 629.01 through 15. They turned
out to be a successful design; their maximum speed was 85 km/h, but they
reportedly attained 110 km/h (presumably running smokebox first) with no
particular problems. Further orders came from kkStB (Kaiserlich-königliche
österreichische Staatsbahnen),
for twenty-five examples: these were numbered 629.01 through 25, so after Südbahn had been incorporated into kkStB, their engines were re-numbered 629.101
through 115 to avoid confusion. Of these forty locomotives, fifteen went to
Czechoslovakia and post-war BBÖ were left with the rest (including all
from Südbahn). Production continued, further
batches being delivered between 1920 and 1922 (629.26 through 55) and between
1926 and 1927 (629.56 through 80). The latter batch featured Lentz valve
gears. Last five examples, numbered 629.500 through 504 and built in 1927,
were fitted with Caprotti valve gears, which did
not prove successful and were later replaced with conventional piston valves.
Austrian locomotives were built by StEG, Wiener
Neustadt and Krauss Linz. After the Anschluss they were
taken over by DRG and given service numbers 77 201 through 265, 266
through 280 (former Südbahn
engines) and 281 through 285 (class 629.5). Class 629 found remarkable favor in Czechoslovakia.
Apart from acquiring fifteen kkStB 629s,
Czechoslovakian state railways ČSD placed further orders. All these
engines were later re-classed 354.1. Production continued until 1941 and
totaled 219 examples from Škoda (198),
PČM (fifteen) and Breitfeld-Danĕk
(six). Later batches featured numerous improvements and modifications,
including two steam domes connected by a horizontal tube of large diameter
(typical for many pre-war Austrian engines) and redesigned steam superheater. Five were fitted with Lentz valve gears;
just as with their Austrian counterparts, this did not prove successful. Last
fifteen examples were completed under German supervision for the railways of
Protectorate (Böhmisch-Mährische Bahn, ten, 1940) and Slovakia (five, 1941). They
featured modified boilers and single steam domes and were the only variant
fitted with smoke lifters. 49 354.1s were impressed into DRG as 77 301
through 349; further five (77 350 through 354) were renumbered only formally
and leased to BMB. All were returned after the war. ČSD also
obtained two ex-BBÖ engines (354.1500 and 354.1501); five went to
Yugoslavia and were impressed into JDŽ state railways as class 18. No locomotives of this type were transferred to
Polish state railways after WWI as a part of war reparations, but in 1921 ten
brand-new 629s were ordered in Austria from Krauss Linz. The reasons
for ordering such a small batch of untypical locomotives are not clear.
Deliveries were completed in 1922 and these engines were classed OKm11.
According to some sources, they were initially referred to as ‘class 629’,
although they were never classed in such manner. In accordance with their
original assignments, they operated mainly in southern and south-eastern
Poland, in conditions similar to those they had been designed for. In 1939 DRG took over three OKm11s, later
re-numbered 77 286 through 288. Seven OKm11s fell into Soviet hands; in
1941 all of them, awaiting re-gauging, became German war booty. Of these
engines, two were given DRG numbers 77 289 and 77 290; four
served with Ostbahn, probably with their
original numbers. The fate of the OKm11-10 is unclear. According to LP,
it was possibly handed over to Organisation
Todt and designated OT 26, but confirmation is
lacking. According to the monographic article by Ryszard
Stankiewicz (see References), this locomotive was
taken over by Wehrmacht and handed
over to Romanian authorities in 1942. ITFR lists this engine (Krauss
Linz 1289/1922) as being acquired by CFR after the war and
impressed into service as 231.902; Polish service number, however, is not
mentioned. All five engines of this type operated by DRG were passed
over to ÖBB after the war. Four of them returned to PKP shortly
afterwards and were transferred to north-eastern Poland, but their service
was short and the last one, OKm11-2 (pre-war OKm11-8, Krauss Linz 1287/1922), was withdrawn in November 1954. The fifth
one, pre-war OKm11-6, was returned from Hungary in February 1953; despite
being given new service number OKm11-5, it saw no service and was soon
scrapped. Post-war service of these locomotives was
comparatively long. In Austria last were withdrawn in 1976 and in
Czechoslovakia in 1978. As many as eight have been preserved, in Austria
(three, two operational), Czech Republic (two, one operational), Lichtenstein
(one, operational), Slovakia (one) and Slovenia (one, plinthed).
Main technical data
1)
Including production in Czechoslovakia. 2)
Depending on variant. List of vehicles can be found here. References
and acknowledgments
-
LP, EZ, ITFR, EDÖ; -
Monographic article by Ryszard
Stankiewicz (SK
vol. 6/2020). |
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