SU46 and ST46

 

SU46_1

 

SU46-039 (HCP 311/1977), Kościerzyna, February 5, 2003.

 

SU46_2

 

SU46-009 (HCP 277/1976), Hel, August 16, 2003.

 

SU46_3

 

SU46-047 (HCP 319/1977), Zawidów, September 30, 2003 (here SU46s take over heavy freight trains from Czech Republic).

 

SU46_20

 

Another picture of the SU46-047, taken at the Węgliniec depot on July 16, 2008. On the right there are SU46-025, SU46-032 and an ASF battery-powered switcher.

 

SU46_4

 

Another SU46 in Zawidów: this time SU46-035 (HCP 306/1977), June 29, 2005.

 

SU46_15

 

And yet another: SU46-025, March 17, 2008.

 

 SU46_5

 

SU46-014 (HCP 282/1976), Legnica, July 1, 2005.

 

SU46_14

 

Another picture of the SU46-014, taken near the Poznań Franowo depot on February 18, 2008.

 

SU46_sc

 

SU46, production variant; side drawing by M. Ćwikła from the monograph quoted in references.

 

SU46_6

 

SU46-010 (HCP 278/1976) with passenger train 15521 to Pisz. Ruciane Nida, October 16, 2005.

 

SU46_7

 

SU46-054 – the last one built – photographed in Zgorzelec on December 21, 2005, with train 511 from Wrocław.

 

SU46_8

 

SU46-032 (HCP 300/1977), sporting new PKP Cargo livery; Legnica depot, June 9, 2006. This livery variant was short-lived.

 

SU46_9

 

Most SU46s in the PKP service have, however, retained their traditional green livery: SU46-004, Ełk, June 15, 2006.

 

SU46_10

 

SU46-026 ready to depart from Zgorzelec to Wrocław; photo taken on December 15, 2006.

 

SU46_11

 

SU46-029, photographed at exactly the same location on April 27, 2007...

 

SU46_13

 

...and SU46-026, spotted at the Węgliniec depot on the same day...

 

SU46_12

 

...together with SU46-043.

 

SU46_16

 

Another picture of SU46-029, taken in Zawidów on April 17, 2008

 

SU46_23

 

…and yet another, Węgliniec station, October 20, 2008.

 

SU46_17

 

SU46-033, photographed in Wolsztyn on May 2, 2008.

 

SU46_25

 

The same locomotive in Zawidów, June 2, 2009.

 

SU46_18

 

Zawidów again: SU46-013, July 14, 2008.

 

SU46_21

 

The same locomotive, photographed at the Węgliniec station two days later.

 

SU46_19

 

SU46-008, photographed at the Węgliniec depot on the same day.

 

SU46_22

 

SU46-015, Korsze, September 9, 2008.

 

SU46_24

 

SU46-031, photographed at the Bolesławiec station on March 20, 2009.

 

SU46_27

 

SU46-017, Węgliniec depot, August 5, 2009.

 

SU46_26

 

Once again SU46-026, photographed on the same3 occasion: new (final?) PKP Cargo livery version.

 

SU46_28

 

SU46-043 again, but this time in new livery: Zgorzelec, September 25, 2009.

 

SU46_29

 

SU46-011, photographed in Zawidów on February 17, 2010.

 

SU46_30

 

The next day: SU46-007 and SU46-011 double-heading a draft of dumpcars, heading for the Turów power station in Bogatynia. Dumpcars are loaded with limestone, used in low-emission combustion systems.

 

SU46_31

 

Another picture taken at almost the same location: SU46-047 at the Turoszów station (closed in early 2000s). February 17, 2011.

 

SU46_32

 

Two picures, taken at the Węgliniec depot on March 27, 2011: SU46-047…

 

SU46_33

 

…and SU46-048. Both display the ‘ultimate’ (?) PKP Cargo livery.

 

SU46_34

 

Back to Zawidów (I used to visit this station quite often): SU46-013…

 

SU46_35

 

…and SU46-022. Despite different liveries, both display new UIC numbers. July 26, 2011.

 

SU46_36

 

SU46-048, Żagań, November 24, 2008…

 

SU46_37

 

… and SU46-033 (fill ‘er up!), location and date unknown. Both photos by Michał Korfel (from my collection).

 

ST46_1

 

Modernized ST46-01, photographed at the Turoszów station on May 23, 2013.

 

 

Another picture of the ST46-01, taken at the same location on October 31, 2013.

 

SU46_38

 

SU46-051 (HCP 323/1977), location and date unknown. Photo from my collection.

 

SU46_39

 

SU46-054 again: Kędzierzyn Koźle, June 1991. Photo by Mariusz Plewka (from my collection).

 

SU46_40

 

SU46-008 (HCP 276/1976) somewhere in Poland, date unknown. Photo from my collection.

 

SU46_41

 

Another photo from my collection: SU46-046 (HCP 318/1977), Kłodzko, May 1991.

 

SU46_42

 

SU46-030, photographed in Ełk on May 11, 2003. Photo by Rafał Roskosz (from my collection).

 

SU46_43

 

Another picture by the same author: SU46-054 with a local train near Dytmarów, November 5, 2003.

 

 

Four more pictures from my collection: SU46-026, Kamieniec Ząbkowicki, date and author unknown…

 

 

…SU46-034, Kędzierzyn-Koźle, April 29, 2000, photo by M. Plewka…

 

 

SU46-041, Legnica, February 27, 1999, the same author…

 

 

…and SU46-017, Kędzierzyn-Koźle again, date unknown, the same author.

 

 

SU46-004, PKP Cargo, Olsztyn Główny station, July 2, 2015.

 

 

Three pictures by Marek Niemiec (from my collection): SU46-054, Jaworzyna Śląska, June 9, 1995…

 

 

… SU46-037, Legnica, August 31, 1996…

 

 

… and SU46-042, location and date unknown.

 

 

SU46-029, Poznań Franowo depot, June 7, 2023. This locomotive is owned by PKP Cargo and is a heritage machine. Photo by Gabriel Kliponis (postcard from my collection).

SP45, first line diesel locomotive built in Poland, was successful, but soon proved too weak for heavy passenger trains. The need for a stronger machine was recognized quite soon and as early as in March 1972, when first SP45s were entering service with PKP, a specification was drawn up for their more powerful development. Initially a variant with two 1200 hp diesels (most probably a8C22W) was contemplated, but finally a more conventional layout with the up-rated 2112SSF engine, built under FIAT license, was chosen. This diesel – designated W2112SSF – were basically the same as in SP45, but with higher supercharging the rated power was boosted from 1700 hp to 2250 hp. Specific fuel consumption remained almost unchanged.

Apart from more powerful diesel and new electric motors, new locomotive – designated SU46 –  had many other improvements, including a generator for 3000 V dc car heating – the first of that kind installed in a Polish locomotive, which supplanted obsolete steam heating installation. This modification was later retroactively introduced in most SP45s during overhauls, their designation changing from SP45 to SU45. Externally new locomotive differed in having more angular body, perhaps aesthetically inferior, but easier to manufacture.

Prototype SU46-001 (factory designation type 303D, s/n 268/1974) was rolled out in November 1974 and second example followed next April. Service evaluation revealed several minor shortcomings, concerning mainly electric and hydraulic systems, but these were soon eradicated and between 1976 and 1977 HCP built further 50 machines. All were supplied to PKP, to be joined later by two prototypes – SU46-002 was accepted in March 1978. Termination of the SU46 production had nothing to do with technical matters: in 1976 HCP were obliged to undertake design and manufacture of a two-unit heavy electric freight locomotive, based on EU07 (to emerge in 1977 as ET41) and, at the same time, it was agreed among the Eastern Block countries that heavy road diesel locomotives shall not be built in Poland. Thus, instead of producing a successful indigenous locomotive, Poland purchased well over 1,000 Soviet ST44s with lower output and higher fuel consumption. This had nothing to do with either economy or common sense and perhaps only railway fans benefited from the deal…

Discontinuation of the diesel locomotives production at HCP immediately resulted in lack of spares for existing machines. Problems with diesel engines were particularly acute, as production of the W2112SSF was also halted. As a result, availability of SP45s and SU46s in PKP service deteriorated rapidly. Many local passenger trains had to be hauled by steam locomotives or diesel freighters with heating cars. Thus, in 1984, Ministry of Transport issued a specification calling for delivery of 267 slightly modified SU46s. Deep economic crisis, however, turned these plans into a mere wishful thinking. It proved impossible to maintain simultaneous production of electric and diesel locomotives at HCP and, as the former were given priority, only two more SU46s were built in December 1985. These machines – SU46-53 and SU46-54 – differed from their predecessors only in minor details and factory designation remained unchanged (externally they could be distinguished by different louvers on side walls). Proposed export variant, type 308D for Greek state railways OSE, with many minor improvements, never saw fruition and production of diesel locomotives at HCP was thus finally terminated with last two SU46s.

First SU46s in PKP service were used mainly with heavy express passenger trains, for which SP45s had been too weak (double-heading had not been uncommon). Modest deliveries of heavy passenger diesel locomotives never allowed for complete elimination of steam traction, which remained in regular service in Poland much longer than in other European countries. As electrification progressed, steam finally disappeared and later many SU46 were relegated to secondary lines; for a number of years a SU46 with just one or two coaches was not an uncommon view. Despite their designation, which implies a universal locomotive, they were initially seldom used with freight trains; later, however, they often appeared on the Węgliniec-Horka line between Poland and Germany, as Germans were reluctant to let ST43s in. With gradual introduction of diesel railcars, which offer much better economy on secondary lines, more and more SU46s were shifted to freight traffic.

 Two prototypes were withdrawn in 1990 (both were later scrapped) and several more were written off in late 1990s, when almost 100 heavy passenger diesels were declared surplus by PKP (in fact, most of them were unserviceable examples, awaiting spares, often for several years). When PKP was split into several companies in 2001, SU46s went to PKP Cargo which, according to rosters quoted in AL, in 2004 had 36 examples. PKP InterCity hired some of them, but later decided to introduce a new diesel locomotive for passenger traffic, which finally materialized in 2014 as class SU160 (factory type 111Db) from PESA.

There were plans to modernize 30 SU46s until 2005 and fit them with new diesel engines; however, these plans, conceived in late 1990s, failed to materialize. In late 2007 it was announced that a modernization program, including replacement of obsolete diesel engines and fitting new generators (at least 1450 kW to supply traction motors and about 440 kW for heating), should be launched in a short time. These plans also did not see fruition. Planned introduction of new passenger diesels and withdrawals of old ST43s and ST44s from PKP Cargo brought about yet another plan and this finally materialized. In 2011 SU46-049 (HCP 321/1977) was rebuilt by PESA and fitted with the MTU 12V4000R43L 12-cylinder diesel engine, de-rated to 2500 hp. Old traction motors were retained. Car heating equipment was removed and, apart from many minor improvements, cab air-conditioning system and new rectangular headlights were fitted. ‘New’ locomotive (type 303Da) was re-designated ST46-01, as it was intended for freight traffic only. It was outshopped in December 2011 and after service tests was assigned to the Węgliniec depot. There were plans to modernize ten (some sources give even twenty) SU46s to this standard during a few years, but in the end ST46-01 remained the sole example. According to www.kolejowaklatka.org, this locomotive is fitted with the 315/1977 number plate, which previously belonged to SU46-43 (badly damaged by fire in 2007). In mid-2017 34 SU46s still existed, but only eight were serviceable. In late 2021 only three examples (SU46-29, -31 and -35) were operational, with remaining service life estimated at two years at most. Two more (SU46-34 and -54) physically existed, but were cannibalized for spares. These are plans to retain three locomotives of this type for preservation.


 

Main technical data – SU46

 

No.

Parameter

Unit

Value

1.

Years of manufacture

-

1974 – 1977 (1985)1)

2.

Total built / used in Poland

-

54 / 54

3.

Axle arrangement

-

Co’Co

4.

Transmission type

-

electric 725 V

5.

Design maximum speed

km/h

120

6.

Prime mover type

-

W2112SSF

7.

Engine rating

kW/hp

1654 / 2250

8.

Bore x stroke

mm x mm

210 x 230

9.

Number of cylinders

-

12

10.

Number of electric motors

-

6 x LSm-493

11.

Rated output of electric motors

kW

6 x 225

12.

Main reduction gear ratio

-

18:67

13.

Diameter of drivers

mm

1100

14.

Total weight

kg

105 000

15.

Axle load

T

17.5

16.

Axle base

mm

14 050

17.

Overall length

mm

18 990

18.

Maximum width

mm

3 034

19.

Train heating

-

electric 3000 V

20.

Brake type

-

Oerlikon

 

1)      Two additional examples built in 1985.

 

Main technical data – ST46

 

No.

Parameter

Unit

Value

1.

Years of manufacture

-

20121)

2.

Total built / used in Poland

-

1

3.

Axle arrangement

-

Co’Co

4.

Transmission type

-

electric 725 V

5.

Design maximum speed

km/h

120

6.

Prime mover type

-

MTU 4000

7.

Engine rating

kW/hp

1840 / 2500

8.

Bore x stroke

mm x mm

9.

Number of cylinders

-

12

10.

Number of electric motors

-

6 x LSm-493

11.

Rated output of electric motors

kW

6 x 225

12.

Main reduction gear ratio

-

18:67

13.

Diameter of drivers

mm

1100

14.

Total weight

kg

102 000

15.

Axle load

T

17.0

16.

Axle base

mm

14 050

17.

Overall length

mm

18 990

18.

Maximum width

mm

2 900

19.

Train heating

-

-

20.

Brake type

-

Oerlikon

 

1) Rebuilt from SU46.

 

References and acknowledgments

 

-       Monograph HCP Diesel Locomotives, Classes SP45, SU46, SP47 by Marek Ćwikła and Paweł Terczyński (Kolpress, 2004);

-       www.kolejowaklatka.org (website by Marek Dąbrowski);

-       SK, various issues.