Ok103

 

799px-S_3-5

 

Bavarian No. 3303 (Maffei 2353/1903), possibly a factory photo. After WWI this engine went to France. Source: www.pl.wikipedia.org.

 

Ok103_sc

 

Side drawing of class S 3/5 N from Lokomotiv-Archiv Bayern (see references).

 

Among German locomotives acquired by PKP after WWI, the majority were of Prussian origin. Railways of other German lands, however, also had their contributions – far less numerous, but by no means less interesting. An example is Among oddities and rarities in the PKP inventory after WWI was a single S 3/5 N of Bavarian state railways (Königlich Bayerische Staatseisenbahnen). Between 1903 and 1907, J.A.Maffei of Munich delivered 39 engines of this type – four-cylinder compounds running on saturated steam, numbered 3301 through 3340 (No. 3329 was the prototype of class S 3/5 H with Schmidt-type superheater, of which thirty examples were eventually built). With 1870 mm drivers and maximum speed of 110 km/h, they served as light express locomotives and were assigned to Munich I and Nuremberg depots. Later engines of this type, built from 1904 onwards (starting from 3311) had boilers shortened by 300 mm; with boiler pressure increased from 14 to 16 bar, they were slightly heavier, but effect on performance was marginal.

After WWI, twenty locomotives of this type were impressed into DRG as class 174. Between 1924 and 1925 most were rebuilt and fitted with steam superheaters, but their designation was not changed. Withdrawals started in early 1930s and only seven engines, all with ‘short’ boilers and superheaters, survived until WWII. The last one, 17 415 (former 3326, Maffei 2421/1905), was withdrawn in January 1948. French railways took over eighteen examples, which were impressed into Chemins de Fer de l’Est (thirteen, numbered XI.3351 through 3363) and Chemins de Fer d’Alsace-Lorraine (five, class S9, numbered 982 through 986 – ‘original’ class S9 comprised eighty De Glehn locomotives, built from 1906 onwards). Polish state railways received one engine of this type, former No. 3333 (Maffei 2601/1907). Initially it was designated P8Bw, the superscript standing for ‘Bawaria’, or Bayern, although had nothing to do with class P8, apart from axle arrangement. In 1925 it was re-designated Ok103-1. It seems probable that this untypical locomotive had been brought from France for evaluation purposes (just like the single Prussian G12, later Ty1, or class C of the Königlich Wüttembergische Staatseisenbahn, which became Om101), but this is just a conjecture. Ok103-1 still remained in the PKP inventory in 1927, but disappeared before 1931. No details concerning her service are available. Not a single example of this beautiful engine has survived until today.

 


Main technical data

 

No.

Parameter

Unit

Value

1.

Years of manufacture

-

1903 – 1907

2.

Total built / used in Poland

-

39 / 1

3.

Tender class

-

4.

Axle arrangement

-

2-3-0

5.

Design maximum speed

km/h

110

6.

Cylinder bore

mm

2 X 335 / 2 X 570

2 X 340 / 2 X 5701)

7.

Piston stroke

mm

640

8.

Engine rating

kW/hp

810 / 1100

9.

Tractive effort

kG

10.

Boiler pressure

MPa

1.43 / 1.631)

11.

Grate dimensions

m X m

3.27 m2

12.

Firebox heating surface

m2

14.5

13.

Distance between tube plates

mm

4 850 / 4 5501)

14.

Number of flue tubes

-

278

15.

Heating surface of flue tubes

m2

196.0 / 191.01)

16.

Number of smoke tubes

-

-

17.

Heating surface of smoke tubes

m2

-

18.

Evaporating surface, total

m2

210.5 / 205.51)

19.

Superheater heating surface

m2

-

20.

Diameter of drivers

mm

1870

21.

Diameter of idlers front/rear

mm

950 / -

22.

Total weight, empty

kg

23.

Total weight, working order

kg

69 300 / 69 8001)

24.

Adhesive weight, working order

kg

46 200 / 46 6001)

25.

Weight with tender, empty

kg

26.

Weight with tender, working order

kg

27.

Maximum axle load

T

15.4 / 15.51)

28.

Axle base (with tender)

mm

16 712

29.

Overall length (with tender)

mm

19 325

30.

Brake type

-

 

1)      Later examples from 3311 onwards (since 1904).

 

References and acknowledgments

 

-       TB vol.1, LP;

-       Lokomotiv-Archiv Bayern by Heinz Schnabel (Transpress, 1987);

-       www.lokomotive.de (website by Ingo Hütter);

-       www.pl.wikipedia.org.