|
OKi1-28, photographed at the Railway Museum
in Warsaw on May 25, 2005.
The same engine, photographed on September 5, 2006.
A drawing from the LHW
catalogue card shows LBE
No.125 ‘Fuchs’ (Linke-Hofmann 334/1906). This engine was sold to the Altona-Kaltenkirchen-Neumünster railway
in 1923 and served there as No.18 until 1953. From my collection.
Class 740-3 side drawing, © Lokomotiv-Revue; source: TB vol.2.
KPEV class T11 ‘Berlin 2132’ (Vulcan
2032/1903). Postcard from my collection.
Berlin 2164, Borsig 5425/1904, location and date
unknown (probably factory photo). In 1925 this locomotive became 74 027,
but was withdrawn four years later. Photo from my collection.
74 101 (ex ‘Berlin 7584’, Union 1399/1905), photographed at the Berlin Lehrter Bahnhof depot on June
15, 1932. This engine was written off in August 1933. Postcard from my
collection.
|
Prussian state railways KPEV
designated both passenger and freight tank engines with capital T, for Tenderlokomotive. After steam superheating had
been introduced, it was decided to use even and odd number for engines
running on superheated and saturated steam, respectively. Thus, T9 was a
freight locomotive with 1350 mm drivers and maximum speed set at 60 to 65
km/h, built in large numbers and three main variants. Next was T10, a modern
passenger engine for suburban traffic with 2-3-0 axle arrangement, 1750 mm drivers and
maximum speed of 100 km/h, of which only twelve were built. T11, designed by
renowned Robert Garbe as a development of class T93,
in fact preceeded T10 by a few years and was a less
advanced design, with 1500 mm drivers, single-axle Krauss-Helmholtz lead
truck, tractive effort of 8.6 tonnes and maximum
speed of 80 km/h. Prototype was completed by Union-Gießerei
of Königsberg in 1903 and 470 examples were built
for KPEV until production terminated in 1910. The majority came from Union (364 examples), the rest being supplied by
Borsig, Hohenzollern and Vulcan.
Furthermore, Linke-Hofmann Werke built nine almost identical machines for Lübeck-Büchener Eisenbahn
(LBE) in
three small batches, between 1906 and 1908. Most T11s ran with suburban trains; S-Bahn in Berlin
alone received 141 examples.
Robert Garbe
was one of the keenest advocates of single-expansion engines running on
superheated steam; no wonder, thus, that such derivative of T11 appeared even
before the latter was ordered in quantity. In 1905 it was accepted as class
T12 and was eventually destined to outnumber its predecessor: over 1000 were
built until 1923. T12 offered more power and much better economy and
therefore almost immediately started to supplant its older kinsman.
After WWI, newly-formed DRG
were left with 358 T11s, classed 740-3. In 1926 twenty were
rebuilt with steam superheating, but this program was not proceeded with, as
electrification of suburban lines rendered these engines surplus. In
particular, electrification
of the S-Bahn between 1924 and 1933 left a
few hundred tank engines with no job. While more modern T12s were relegated
to secondary lines and switching, many T11s were withdrawn. In late 1920s and
early 1930s as many as 204 locomotives of this type were written off, some
after less than twenty years in service. Two more followed during WWII;
furthermore, a few were sold to various private local railways. Similarly, of
nine examples in the LBE inventory (which had not been taken over by DRG),
seven were written off between 1926 and 1932 or sold; only two survived until
1953. After WWII, DB were left with just 65 engines of this type, most
were withdrawn in early 1950s. DR had sixty; a few soldiered on until
late 1960s, quite a lot went to industry. Four examples were taken over by
Soviet MPS (Ministry of Transport), but their service was probably
very short.
Polish
railways were a major recipient of T11s after WWI. As many as 56 examples
were taken over and impressed into service. They were classed OKi1 and given
service numbers from 1 to 52; four operated in Gdańsk were
designated OKi1-1Dz through –4Dz, where Dz stood
for ‘Danzig’ (in fact, all four had been
operated in Gdańsk
by KPEV before 1918). Most
of these obsolescent, but reliable engines served in Upper
Silesia on local lines. Two (OKi1-5 and OKi1-24) were withdrawn
before 1936, the rest survived until the next war. In September 1939 the
majority were taken over by DRG and given service numbers after those
withdrawn before the war; six fell into Soviet hands (one after a brief
period with Lithuanian railways LG), but five of them were later
re-captured by Germans. After 1945, thirty-six were returned to PKP, but one (former OKi1-3Dz) was not
given new service number and written off in 1946. Furthermore, a number of DRG
engines were taken over. According to the Ingo Hütter’s
database (www.locomotive.de), they numbered 22, of which
five were not given service numbers and shared the fate of the OKi1-3Dz. It
seems possible, however, that two of them might be impressed into service as
OKi1-47 and OKi1-48, on which information is lacking. Anyway most reliable
sources agree that post-war class OKi1 numbered 52 examples. These
comparatively weak engines performed best on flat-profile lines, so all were
assigned to the regional railway management in Gdańsk. Some were
later relegated to auxiliary duties and switching. Their withdrawal started
in early 1950s and only eleven survived with PKP until 1960. Between
1952 and 1959 sixteen were transferred to various industrial establishments
and some enjoyed there a few years’ lease of life. Last three OKi1s in the PKP service were withdrawn in 1966.
One of them (OKi1-28, Borsig
5424/1904, KPEV ‘Berlin 7560’, then
OKi1-14 and 74 104) has been preserved and can now be seen at the static
display in the Railway
Museum, Warsaw. As far as I
know, only one more engine of this type still exists. Union 1602/1908 (KPEV ‘Hannover 7512’, then DRG 74 231) was kept by DR
after WWII and remained in service until 1968, when it was transferred to an
industrial plant. Plinthed at a railway school
premises in Erfurt
in 1974, it was finally transferred to Museums-Eisenbahn Minden in 2000 and sometimes runs with
special trains.
Main technical data
|
No.
|
Parameter
|
Unit
|
Value
|
|
1.
|
Years
of manufacture
|
-
|
1903 – 1910
|
|
2.
|
Total
built / used in Poland
|
-
|
479 / 561) – 522)
|
|
3.
|
Tender
class
|
-
|
-
|
|
4.
|
Axle
arrangement
|
-
|
1-3-0
|
|
5.
|
Design
maximum speed
|
km/h
|
80
|
|
6.
|
Cylinder bore
|
mm
|
2 ´ 480
|
|
7.
|
Piston
stroke
|
mm
|
630
|
|
8.
|
Engine
rating
|
kW/hp
|
382 / 520
|
|
9.
|
Tractive
effort
|
kG
|
8 600
|
|
10.
|
Boiler
pressure
|
MPa
|
1.22
|
|
11.
|
Grate
dimensions
|
m X m
|
1.75 ´ 0.99
|
|
12.
|
Firebox
heating surface
|
m2
|
8.7
|
|
13.
|
Distance
between tube plates
|
mm
|
4000
|
|
14.
|
Number
of flue tubes
|
-
|
209
|
|
15.
|
Heating
surface of flue tubes
|
m2
|
104.27
|
|
16.
|
Number
of smoke tubes
|
-
|
-
|
|
17.
|
Heating
surface of smoke tubes
|
m2
|
-
|
|
18.
|
Evaporating
surface, total
|
m2
|
112.973)
|
|
19.
|
Superheater
heating surface
|
m2
|
-
|
|
20.
|
Diameter
of drivers
|
mm
|
1500
|
|
21.
|
Diameter
of idlers front/rear
|
mm
|
1000 / -
|
|
22.
|
Total
weight, empty
|
kg
|
48 300
|
|
23.
|
Total
weight, working order
|
kg
|
62 600
|
|
24.
|
Weight
on drivers, working order
|
kg
|
47 400
|
|
25.
|
Weight
with tender, empty
|
kg
|
-
|
|
26.
|
Weight
with tender, working order
|
kg
|
-
|
|
27.
|
Maximum
axle load
|
T
|
16.0
|
|
28.
|
Axle
base (with tender)
|
mm
|
6 350
|
|
29.
|
Overall
length (with tender)
|
mm
|
11 190
|
|
30.
|
Brake
type
|
-
|
Knorr
|
1)
After WWI.
2)
Plus six more with no service numbers, written off
in 1946.
3)
Some sources give 116.4 sq.m.
References
and acknowledgments
-
TB vol. 2, LP;
-
www.lokomotive.de
(database by Ingo Hütter).
|