Pt31
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An unidentified Pt31 on display at an industrial exhibition in Warsaw,
September 1936. Source: National
Digital Archives (used by permission).
Pt31-64 + 32D29-37, Chabówka Rolling Stock Heritage
Park, April 13, 2004
Another picture of the Pt31-64, taken on
…and yet another: May 6, 2017.
Pt31-49 under restoration at the Jaworzyna Śląska
depot; photo taken on
Side drawing of Pt31, taken from PNP.
Pt31-17, somewhere in
Good color photos of Polish trains from 1970s
are extremely rare. Pt31-32 with a passenger train from Rozwadów to Ostrowiec
was photographed by Geoff Plumb on
Pt31-27, Fablok 607/1935 (pre-war
Pt31-17, then DRG 19 109),
photographed at the Warszawa Praga depot on May 15,
1968. This engine was written off in May 1975. Postcard from my collection. |
After
WWI, Polish railways took over about 350 express locomotives of German
(mainly Prussian) and Austrian origin. Most of them, however, were obsolete
and weak machines with only two driven axles. Those that could be considered
modern at that time included Austrian classes 210 and 310, re-designated Pn11
and Pn12, respectively (the former running on saturated steam) and Prussian
classes S10, S101 and S102 (in Polish service, Pk1, Pk2
and Pk3); their total number was slightly over eighty machines. Production of
freight and later also passenger locomotives was given priority. In late 20s,
however, lack of express locomotives became obvious, as PKP had only
83 express engines. Os24s, used with some express trains, were not
satisfactory and their service speed had to be reduced, due to poor running
qualities. Ok1s and Ok22s, used for the same purpose, were too slow and weak.
New machine was thus necessary. Locomotive
design in Poland was, to a large extent, influenced by German patterns, which
favored express locomotives with three driven axles. Two-axle lead truck was
considered mandatory for a fast machine and, with a rear idle axle necessary
to support the weight of a large firebox, this led to the 2-3-1 arrangement,
or Pacific – one of the most common ones for express locomotives in
Europe. It was, however, decided to use four driven axles, as new engine was
intended for heavy drafts, 750 tonnes or even more. 2-4-1 axle arrangement
resulted in a long machine, so it was suggested that for speeds up to about
100 km/h a single-axle lead truck might suffice. In order to resolve this
question, Ministry of Transport ordered two prototypes: Pu29 (2-4-1) from HCP (Cegielski) of Poznań and
Pt29 (1-4-1) from First Locomotive Factory in Poland (Fablok)
of Chrzanów. Due to some delay – an order from Bulgarian state railways BDŽ
had been given priority – Pt29 appeared later than planned and was
re-designated Pt31. 1-4-1 axle arrangement was first conceived in the USA;
known there as Mikado, it was very popular, mainly with freighters. In
Europe Mikados were considered universal machines, but only French
railways ordered them in large numbers; classes 141P and 141R were one of the
last and best known steam locomotives operated by SNCF. Fablok had had some experience with 1-4-1s, having
built locomotives with this axle arrangement for Morocco (class 141A, 12
examples) and above-mentioned for Bulgaria (class 01, 10 examples). Pu29,
although entirely successful, immediately proved too long for most
turntables; despite good performance, its output was limited to three
examples. Pt31 won by being shorter by just 76 centimeters. It was also
lighter by seven tonnes, but maximum axle loads were comparable. Both these
locomotives had much in common; in particular, their steam engines were the
same, as was the diameter of drivers. Contrary to its larger competitor, Pt31
had beam-type frame and shorter boiler (by 300 mm); number of smoke tubes
was, however, increased from 103 to 112 and number of flues from 26 to 38, so
both total evaporating surface and superheater surface were slightly increased.
Two-axle lead truck was supplanted by Krauss-Helmholtz single-axle truck;
rear Bissel semi-truck was retained. Three
Pt31 prototypes were ordered in 1931 and the first of them (s/n 518/1932) was
rolled out in October 1932. Tests began immediately and results were
satisfactory, overall efficiency being comparable to that of the
state-of-the-art European machines. Footplate crews praised ease of
maintenance, good running qualities and excellent performance even on steep
gradients. After several minor modifications, Pt31 was accepted as a standard
express locomotive for PKP and
deliveries began in 1934. From eleventh example onwards new, higher smoke
lifters were introduced. All Pt31s were coupled with 32D29 tenders,
originally designed for both Pu29 and Pt31. On
January 1, 1939, PKP had 81
examples and further seventeen were delivered during next eight months. Of
these, 54 were captured by Germans in September 1939 and impressed into DRG service as 19 101 through 154
(these numbers were assigned in 1941). Further twelve examples, ordered by PKP but not delivered before the war,
were completed by Fablok under German
supervision and supplied to DRG as
class 3910 (service numbers from 39 1001p through 1012p, later
re-classed 19 155 through 166), bringing the total output to 110 examples. No
Pt31 was destroyed during hostilities and all remaining 44 machines were
captured by Soviets. Some of them (probably 21) were converted to 1524 mm
track and based in Lwów, retaining their Polish
designations written in Russian script (Пт-31). They were never
returned and last were withdrawn in 1961. The remaining 23 engines were
captured by Germans in 1941; according to PNPP, fourteen were
impressed into DRG service as 19 167 through 180 and the rest were
taken over by Ostbahn and withdrawn in 1944.
Germans – with their unquestionable achievements in railway engineering,
albeit aimed at simplicity rather than technical excellence and superior
economy – held Pt31s in surprisingly high esteem; they were considered
especially suitable for heavy drafts in mountainous regions. No wonder, thus,
that most captured machines were soon transferred to southern Germany and
Austria. In fact, DRG had no
comparable locomotive of indigenous design, apart from Saxonian
class XX HV (later DRG class 19), of which just 23 examples had been
built by Hartmann between 1918 and 1923: a beautiful and good machine,
it was not developed further by DRG. Even ‘Reko’
class 22 with the same axle arrangement, which appeared in the DR
rosters aftere the war, was weaker and heavier on
coal. During
the war, Pt31s were scattered around Eastern and Central Europe and in 1945
only eight were regained by PKP.
The rest served in a number of countries: -
Germany – seven with DB, written off in 1951, and twelve with DR, all
returned to PKP (most in 1955, generally in poor condition, but all
except one restored in service); -
Austria – 42 in all, of which 29 were returned in
1947 and 1948, eight went to MÁV and later to PKP, two were
written off in 1947 and three remained with ÖBB on former Südbahn lines (numbered 919.158, 919.165 and
919.166, withdrawn in 1961); -
Czechoslovakia – eight examples, five of them
classed 488.0 with ČSD service
numbers 488.0500 through 488.0504, all returned to Poland in 1947; -
Hungary – eight from ÖBB, returned in 1952
and 1953, plus one from DRG, not returned, scrapped in 1953; -
Romania – two (ex-Soviet Pt31-38, CFR, later
taken over by NKPS,
and Pt31-48, transferred from DRG in
March 1943 and withdrawn in 1961; -
USSR – 29, none returned; seven served with the
Soviet Army transportation corps and were later transferred to the Far East,
to be impressed into Chinese Eastern Railway in Manchuria; -
one German engine (19 164, Fablok
793/1940) was written off after an accident in 1941. The above
list is based on available sources which reveal some discrepancies. In
particular, according to PNPP, the
above-mentioned seven Soviet engines were not transferred to the Far East,
but written off in Lwów in August 1944. A possible
reason for withdrawing comparatively new and good engines is, however,
unclear. Some
engines that returned were in a very poor condition and were not restored in
service. Total number with post-war PKP was 65 examples, but numbers
ran up to 66, as the sole Pu29-3 was initially erroneously included in
rosters as Pt31-46. They gave good service and remained in use until late
70s. During overhauls they were fitted with firebox circulation tubes (as in
class Pt47) and some were coupled with modified 32D74 tenders. Last engine of
this type in service, Pt31-49 (pre-war Pt31-73, s/n 715/1938), was withdrawn
in February 1980 and then used for some time as a stationary boiler at a food
industry establishment. This machine can now be seen at the Industry and Railway Museum in Jaworzyna Śląska (former loco
depot); its condition is far from satisfactory, but restoration is under way.
Several other examples ended up as stationary boilers; Pt31-28 served in that
inconspicuous role at least until 1996. The second preserved example is
Pt31-64 (s/n 721/1938) at the Railway
Stock Heritage Park in Chabówka. No more
machines have survived until today. Many
view Pt31 the best locomotive ever designed and built in Poland and this
opinion is certainly justified. Shortly after the war it was decided to commence
its production as the basic express engine for Polish railways – once again.
After some modifications it emerged as Pt47 and 180 examples were built, both
by Fablok and HCP. This engine is described under a separate entry.
Main technical data
1)
Including 12 examples supplied directly to DRG in 1939 and 1940. List of vehicles can be found here. References
and acknowledgments
-
Monographic articles by Paweł Terczyński (SK
vol. 11/2003) and by Ryszard Stankiewicz (KMD vol. 1-2/2013); -
Ingo Hütter’s website www.locomotive.de/lokomotivgeschichte/datenbank,
also private communication; - PNPP,
PNP, AP, LP, ITFR;
-
Markus Hoenicka (private communication).
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