TKh3

 

 

The sole surviving T8: prototype Linke-Hofmann 359/1906, photographed in Potsdam on May 17, 1993, by someone who wishes to be known as MPW57. Source: www.commons.wikipedia.org. The engine displays the KPEV livery and is designated Berlin 7001.  

 

 

A locomotive with a history. Elberfeld 7004 (Linke-Hofmann 399/1907) later became 89 011, was sold to Butzbach-Licher Eisenbahn in 1928 (No. 35), then to Dahme-Uckroer Eisenbahn in 1932 (No. 1) and to Brandenburgische Städtebahn in 1938 (No. 61). Taken over by DR in 1950, it became 89 6476 and was sold for scrap in 1966. The picture was taken somewhere in Eastern Germany in 1961. Photo by G. Meyer; source: Brandenburgische Städtebahn (see References).

 

 

Side drawing of the earlier…

 

 

…and later production variants. Source: Lokomotiv-Archiv Preußen (see References).

 

 

 

First tank locomotive running on superheated steam in the KPEV (Königlich Preußische Eisenbahnverwaltung) service was not successful. It was developed against the requirement for a machine suitable for local and secondary lines and also for switching, with maximum speed increased to 60 km/h. It was intended to keep axle load below 14 T, which was recommended by military authorities. Following successful applications of superheaters in express (class S4) and passenger (class P6) locomotives, Robert Garbe designed his first superheated tank engine. Prototype (Linke-Hofmann 359/1906) was assigned to the Magdeburg regional management, where it underwent service tests. Results were not particularly satisfactory. Due to short axle base of only 3400 mm and heavy superheater, weight distribution was quite uneven, with overloaded front axle. Running qualities at higher speeds thus left much to be desired and the engine quickly earned a nickname of ‘bone shaker’. The type was finally standardized as T8 and remained in production until 1909, but only 100 examples were built by Linke-Hofmann (59), Orenstein & Koppel (26) and Hanomag (15). Last examples, built from 1908 onwards, had axle base increased by 200 mm (overall length remained unchanged); in order to improve weight distribution, steam dome was shifted to the rear and sand dome slightly forward. Improvement was, however, marginal. Moreover, axle load exceeded 15 T and was higher than in very successful class T93 which had been in production since 1902. After a few years T8s were relegated exclusively to switching. Two engines, Hanomag 4862/1907 and 4863/1907, were experimentally fitted with Lentz-type poppet valves, but were later converted to standard version.

After WWI German state railways DRG retained 78 examples, classed 890. Despite their comparatively young age, all but six were withdrawn in late 1920s. Only those sold to various private railways and enterprises survived until WWII. Two engines from Lokalbahn AG and two from Mecklenburgische Friedrich-Wilhelm-Eisenbahn (MFWE) were re-entered into DRG rosters in 1938 and 1941, respectively, and re-numbered 89 1001 through 1004. In 1949 DR took over former 89 071 from Kreisbahn Schönermark-Damme and in 1950 89 011 followed, from Brandenburgische Städtebahn. They became 89 6576 and 89 6476, respectively. The former (Orenstein & Koppel 2576/1908) was the last engine of this type in service: sold in 1958 to industry, it remained in use until 1974, albeit last six years only as a stationary boiler.

According to LP, Polish state railways obtained six locomotives of this type, classed TKh3 in 1926. Assignment of service numbers to individual examples is not known. Locomotive types list, issued by the Ministry of Transport in 1927, gives five, so one was probably withdrawn earlier. All were written off before 1931. Virtually nothing is known about their service, but they were probably considered unsatisfactory and were eventually outlived by many older types. Some older sources mention that a few engines of this type served with PKP after WWII, which is incorrect.

Despite early withdrawal of this class in Germany, the prototype survived until today. Initially numbered Magdeburg 7001, later assigned to regional managements in Berlin and then Kassel, it became 89 001 in 1925. Sold to industry in 1926, it later was purchased by Prenzlauer Kreisbahn and then by MFWE. Re-acquired by DRG in 1941, it became 89 1004. Withdrawn from DR in 1966, this locomotive finally ended up in the DB Museum of Halle (Saale).

 


Main technical data

 

No.

Parameter

Unit

Value

1.

Years of manufacture

-

1906 – 1909

2.

Total built / used in Poland

-

100 / 6

3.

Tender class

-

-

4.

Axle arrangement

-

0-3-0

5.

Design maximum speed

km/h

60

6.

Cylinder bore

mm

2 ´ 500

7.

Piston stroke

mm

600

8.

Engine rating

kW/hp

490 / 690

9.

Tractive effort

kG

10.

Boiler pressure

MPa

1.22

11.

Grate dimensions

m X m

1.32 m2

12.

Firebox heating surface

m2

7.5

13.

Distance between tube plates

mm

3 700

14.

Number of flue tubes

-

93

15.

Heating surface of flue tubes

m2

16.

Number of smoke tubes

-

12

17.

Heating surface of smoke tubes

m2

18.

Evaporating surface, total

m2

68.3

19.

Superheater heating surface

m2

16.4

20.

Diameter of drivers

mm

1350

21.

Diameter of idlers front/rear

mm

- / -

22.

Total weight, empty

kg

35 800 / 36 6001)

23.

Total weight, working order

kg

45 700 / 46 5001)

24.

Weight on drivers, working order

kg

45 700 / 46 5001)

25.

Weight with tender, empty

kg

-

26.

Weight with tender, working order

kg

-

27.

Maximum axle load

T

15.2 / 15.51)

28.

Axle base (with tender)

mm

3 400 / 3 6001)

29.

Overall length (with tender)

mm

9 460

30.

Brake type

-

 

1)      Later production variant.

 

References and acknowledgments

 

-       TB vol. 2;

-       LP;

-       Lokomotiv-Archiv Preußen Band 3 by Andreas Wagner (Bechtermünz Verlag, 1996);

-       Die Brandenburgische Städtebahn by Walter Menzel (Transpress, 1983).