SM31 (production model 411D) is a Polish series of

diesel Diesel may refer to: * Diesel engine, an internal combustion engine where ignition is caused by compression * Diesel fuel, a liquid fuel used in diesel engines * Diesel locomotive, a railway locomotive in which the prime mover is a diesel engin ...

shunting locomotives used by PKP and industry.

History

SM31 class had been designed for shunting heavy freight

train In rail transport, a train (from Old French , from Latin , "to pull, to draw") is a series of connected vehicles that run along a railway track and transport people or freight. Trains are typically pulled or pushed by locomotives (often ...

s in large freight stations, works and harbours. The design was elaborated in

Fablok Fablok is a Polish manufacturer of locomotives, based in Chrzanów. Until 1947 the official name was ''First Factory of Locomotives in Poland Ltd.'' ( pl, Pierwsza Fabryka Lokomotyw w Polsce Sp. Akc.), Fablok being a widely used syllabic abbreviat ...

in 1973, mainly on the basis of

SM42 SM42 is the PKP classification system, PKP class for a Polish switcher, shunter diesel locomotive for shunting and light freight traffic, built by Fablok in Chrzanów (manufacturer's designation is Ls800E, designer's designation 6D). History Th ...

locomotive. Production of this series lasted between 1976 and 1981, as well as between 1983 and 1985. In this period PKP bought 167 items of this series machines. A total number of ca. 200 locomotives was produced, with the rest of them servicing

Polish Polish may refer to: * Anything from or related to Poland, a country in Europe * Polish language * Poles Poles,, ; singular masculine: ''Polak'', singular feminine: ''Polka'' or Polish people, are a West Slavic nation and ethnic group, w ...

industry, chiefly

mining Mining is the extraction of valuable minerals or other geological materials from the Earth, usually from an ore body, lode, vein, seam, reef, or placer deposit. The exploitation of these deposits for raw material is based on the economic ...

. Also first two prototypes (SM31-001 and SM31-002) were sold to industrial works, and the last one locomotive for PKP was re-bought from the industry (SM31-170). As the main purpose of this series was shunting heavy freight trains, after its introduction PKP possessed shunters suited for all purposes. For extremely light trains mainly SM03 locomotives were used. Medium light trains were shunted by SM30 series, medium weight trains were left for

engines. The last thing to be done was the introduction of heavy shunter able to work in severe climatic conditions, what did not happen before SM48 were brought to Poland. Today SM31 locomotives are mainly to be found on

Upper Silesia Upper Silesia ( pl, Górny Śląsk; szl, Gůrny Ślůnsk, Gōrny Ślōnsk; cs, Horní Slezsko; german: Oberschlesien; Silesian German: ; la, Silesia Superior) is the southeastern part of the historical and geographical region of Silesia, locate ...

railway tracks, pulling heavy freight trains from works to marshalling yards in

Łazy Łazy is a town in Zawiercie County, Silesian Voivodeship, Poland. Until 1947 the town was the seat of the Rokitno Szlacheckie municipality. In the years 1975–1998 the town administratively belonged to the Katowice province. As of 2019, the ...

Jaworzno Jaworzno is a city in southern Poland, near Katowice. It lies in the Silesian Highlands, on the Przemsza river (a tributary of the Vistula). Jaworzno belongs to the historic province of Lesser Poland. The city is situated in the Silesian Voivod ...

, Szczakowa,

Tarnowskie Góry Tarnowskie Góry (German: ''Tarnowitz''; szl, Tarnowske Gōry) is a town in Silesia, southern Poland, located in the Silesian Highlands near Katowice. On the south it borders the Upper Silesian Metropolitan Union, a megalopolis, the greater Si ...

and

Rybnik Rybnik (Polish pronunciation: ; szl, Rybńik) is a city in southern Poland, in the Silesian Voivodeship, around 38 km (24 mi) southwest of Katowice, the region's capital, and around 19 km (11 miles) from the Czech border. It is ...

. Other engines are deployed at the stations of

Łódź Łódź, also rendered in English as Lodz, is a city in central Poland and a former industrial centre. It is the capital of Łódź Voivodeship, and is located approximately south-west of Warsaw. The city's coat of arms is an example of cant ...

, Nowy Sącz,

Poznań Poznań () is a city on the River Warta in west-central Poland, within the Greater Poland region. The city is an important cultural and business centre, and one of Poland's most populous regions with many regional customs such as Saint Joh ...

, Szczecin and

Wrocław Wrocław (; german: Breslau, or . ; Silesian German: ''Brassel'') is a city in southwestern Poland and the largest city in the historical region of Silesia. It lies on the banks of the River Oder in the Silesian Lowlands of Central Europe, rou ...

Technical data

SM31 is a Co-Co locomotive, what means it runs on two bogies, each equipped with three axles. Bogies are similar in construction to those used in SU45 and SU46 locomotives. This gives SM31 locomotive good performance on highland tracks. Being a typical shunter, SM31 has one crew compartment of the same height as machine and electric compartments. The engine (V8 compression-ignition engine) is in fact a developed version of

locomotive engine, with its total power raised by ca. 50%. The engine propels main alternator, which gives power to six 196 kW

traction motor A traction motor is an electric motor used for propulsion of a vehicle, such as locomotives, electric or hydrogen vehicles, elevators or electric multiple unit. Traction motors are used in electrically powered rail vehicles ( electric multiple ...

Nicknames

Trumna ( En.: '' Coffin'') - from locomotive's angular shape.

References

{{PKP Locomotives Diesel-electric locomotives of Poland Co′Co′ locomotives Standard gauge locomotives of Poland Railway locomotives introduced in 1976 Shunting locomotives