TKt3

DRG 86 283, Orenstein & Koppel 12941/ 1937; I took this photo at the Dampflokmuseum, Neuenmarkt, Germany, on July 30, 1996.

TKt3-16, ex 86 240, Schichau 3286/1935, can now be seen in Chabówka loco depot; photo taken on April 13, 2004.

Side drawing of early version (86 017 to 233), drawing by M.Ćwikła from SK vol.2/ 2003.

Later variant; side drawing from TB

vol. 2…

… and final version (ÜK); side drawing by M.Ćwikła from SK vol. 2/2003.

Another picture of the TKt3-16, taken on July 29, 2006.

TKt3-42, photographed somewhere in Poland in January 1961. Photo from my collection.

 86 002, DRG, MGB Karlsruhe 2357/1928. Probably this is a factory photo.

86 056 (Borsig 14428/1932) remained with DR after WWII; re-numbered 86 1056-0 in 1970, it was transferred to ÖGEG in 1991. Postcard from my collection.

Tank locomotives with the 1-4-1 axle arrangement were very popular in Europe and German class 86, of which almost 800 were built, was among them the most numerous type. Its origin can be traced back to 1924, when German railway authorities decided to introduce several normalized standard-gauge locomotive classes (Einheitsbauarten), covering the entire range from small switchers to heavy freight locos and fast express machines. This decision, leading to development of entirely new machines, might have seemed surprising: Prussian manufacturers, who by far dominated locomotive design in Germany before 1918, had been able to supply modern engines which compared favorably with that used in other European countries. Standardization was, however, given priority. As a result, in late 1930s DRG had, in general, very modern locomotives.

Among other types, it was decided to develop a 1-4-1 tank locomotive for local heavy freight traffic, with axle load not exceeding 15 tonnes, to replace Prussian classes T14 and T14¹. Many elements and sub-assemblies were intended to be interchangeable with that of classes 24 and 64, also designed for local traffic, but lighter. Design of the new machine, designated class 86, was submitted in 1927 and production started the next year, first seven machines being supplied by Maschinenbau-Gesellschaft (MBG) of Karlsruhe. As with other normalized German types, production, which lasted until 1938, was scattered among several companies, to keep them busy. In the case of class 86 there were nine of them: MBG (11 machines), Linke-Hoffman (5), Schichau (118), Krupp (17), Maschinenfabrik Esslingen (23), Borsig (38), Henschel (53), BMAG (18, including one for a private railway) and Orenstein (18); first two of them failed to survive the Great Crisis. Thus, during eleven years, production reached just 301 examples.

After Anschluss, further 77 examples were ordered from WLF (Floridsdorf) and delivered in 1939; this company eventually became the largest source of 86s, supplying 191 machines until production was finally terminated in 1943. Also former Cegielski (HCP) works of Poznań, renamed DWM Posen, joined in 1942 and built 73 examples (86 456 through 487 and 86 835 through 875). Wartime deliveries from Krupp (45), Borsig (22), Henschel (40), BMAG (57) and MBA (formerly Orenstein & Koppel – 46) brought total output to 775 examples. In 1943 all remaining orders were cancelled and, as certain sequences of service numbers had already been reserved, the last machine was accepted as 86 966 (86 1000 was built for a private railway in 1938 and impressed into DRG in 1943).

There were several modifications, including steel firebox (from 86 230 onwards), gradual introduction of welding instead of riveting, modified water and coal boxes, several variants of brakes (it was intended to increase maximum speed) and many minor changes. After successful tests, Bissel semi-truck was supplanted with Krauss-Helmholtz truck from 86 338 onwards, which considerably improved running qualities. Externally, three major versions can be distinguished: initial one with small cutoffs in water boxes, second one (from 86 378 onwards) with much longer cutoffs and final wartime ÜK (Übergangs-Kriegslok), introduced in 1941, with simplified cab and smoke-box door and several equipment items removed; they were slightly lighter than the original variant.

After WWII most of these locomotives remained in Germany, with DB (about 385 examples, in use until 1974) and DR (about 175, in use until 1976). About twenty machines were destroyed during hostilities. Several examples were taken over by Austria (27 machines, class designation unchanged), Czechoslovakia (69 machines, 26 of which were impressed into ČSD as class 455.2 – the last one was withdrawn in 1957, several went to industry) and Soviet Union (according to Kurt H.Miska, over 90; an older source gives 46 examples).

In 1945 Poland took over seven machines built in Poznań, which were considered Polish property; in 1951 one more followed, from Czechoslovakia. Furthermore about 40 German-built locomotives of this type were impressed into service. 46 examples were given PKP service numbers TKt3-1 to 46; at least one more (Schichau 3284/1935) was not repaired and finally scrapped. Most of TKt3s were used in southern Poland, on mountain lines with comparatively weak tracks; they were well suited for such service. Even on poor and uneven tracks their running qualities were considered very good. Despite their designation, many of them hauled passenger trains and due to fast startup and sufficient tractive effort were particularly suitable on suburban lines. With mounting supplies of indigenous TKt48s, designed basically for the same tasks, they were gradually shifted to switching.

Eight examples were written off before 1965, half of them (TKt3-16, 20, 21 and 41) being transferred to collieries; two more (TKt3-1 and 25) served at railway depots. It was intended to withdraw all remaining machines until 1972 and in fact only two survived in the PKP service for longer: TKt3-11 (ex 86 158, Borsig 14486/1934) was written off in March 1974 and TKt3-15 (ex 86 239, Schichau 3285/1935) in January 1975. TKt3-16 (ex 86 240, Schichau 3286/1935), transferred to Zabrze coal mine in 1964, remained in use there until October 1982; this machine, the last Polish TKt3 in service, has been preserved at the Chabówka rolling stock heritage park and is still there on static display. All other examples were scrapped.

TKi3 was a versatile and useful machine. Its successor, TKt48 (with the same axle arrangement), was slightly longer and heavier by some 10 tonnes, with comparable output and tractive effort; due to higher boiler pressure, however, overall characteristic were improved.

Main technical data

No.	Parameter	Unit	Value
1.	Years of manufacture	-	1927 – 1943
2.	Total built / used in Poland	-	775^1) / 47^4)
3.	Tender class	-	-
4.	Axle arrangement	-	1-4-1
5.	Design maximum speed	km/h	70 / 80^3)
6.	Cylinder bore	mm	2 X 570
7.	Piston stroke	mm	660
8.	Engine rating	kW/hp	758 / 1030
9.	Tractive effort	kG	12 300
10.	Boiler pressure	MPa	1.43
11.	Grate dimensions	m X m	2.2 X 1.07
12.	Firebox heating surface	m^2	10.0
13.	Distance between tube plates	mm	4 500
14.	Number of flue tubes	-	110
15.	Heating surface of flue tubes	m^2	61.8
16.	Number of smoke tubes	-	26
17.	Heating surface of smoke tubes	m^2	45.9
18.	Evaporating surface, total	m^2	117.7
19.	Superheater heating surface	m^2	47.0
20.	Diameter of drivers	mm	1400
21.	Diameter of idlers front/rear	mm	850 / 850
22.	Total weight, empty	kg	70 400^5)
23.	Total weight, working order	kg	88 500
24.	Weight on drivers, working order	kg	60 600
25.	Weight with tender, empty	kg	-
26.	Weight with tender, working order	kg	-
27.	Maximum axle load	T	15.6
28.	Axle base (with tender)	mm	10 300
29.	Overall length (with tender)	mm	13 820^2)
30.	Brake type	-	Knorr

1) Some sources give 744 – probably just a mistake.

2) From 91 230 onwards 13 920 mm

3) After reconstruction of brakes

4) Including one machine never restored in service and scrapped

5) 66 850 kg for ÜK.

References and acknowledgments

Detailed description can be found in a monograph article by Paweł Terczyński in SK vol.2/2003. Concise description can be found in TB vol.2. Very comprehensive account is available at Kurt H. Miska’s website http://www-personals.umich.edu/~khmiska.