ET40 is the name for

Bo′Bo′+Bo′Bo′ B-B and Bo-Bo are the Association of American Railroads (AAR) and British classifications of wheel arrangement for railway locomotives with four axles in two individual bogies. They are equivalent to the B′B′ and Bo′Bo′ classifications ...

two-unit freight

electric locomotive An electric locomotive is a locomotive powered by electricity from overhead lines, a third rail or on-board energy storage such as a Battery (electricity), battery or a supercapacitor. Locomotives with on-board fuelled prime mover (locomotive), ...

in service of

Polish Polish may refer to: * Anything from or related to Poland, a country in Europe * Polish language * Polish people, people from Poland or of Polish descent * Polish chicken * Polish brothers (Mark Polish and Michael Polish, born 1970), American twin ...

national rail operator, PKP. The locomotive was produced by

Škoda Works The Škoda Works (, ) was one of the largest European industrial conglomerates of the 20th century. In 1859, Czech engineer Emil Škoda bought a foundry and machine factory in Plzeň, Bohemia, Austria-Hungary that had been established ten ye ...

in the

Czechoslovakia Czechoslovakia ( ; Czech language, Czech and , ''Česko-Slovensko'') was a landlocked country in Central Europe, created in 1918, when it declared its independence from Austria-Hungary. In 1938, after the Munich Agreement, the Sudetenland beca ...

History

During the 1960s and 1970s, a massive increase in freight transport was seen in Poland, especially on the routes between

Silesia Silesia (see names #Etymology, below) is a historical region of Central Europe that lies mostly within Poland, with small parts in the Czech Silesia, Czech Republic and Germany. Its area is approximately , and the population is estimated at 8, ...

coal mine Coal mining is the process of resource extraction, extracting coal from the ground or from a mine. Coal is valued for its Energy value of coal, energy content and since the 1880s has been widely used to Electricity generation, generate electr ...

s and Polish

Baltic Baltic may refer to: Peoples and languages *Baltic languages, a subfamily of Indo-European languages, including Lithuanian, Latvian and extinct Old Prussian *Balts (or Baltic peoples), ethnic groups speaking the Baltic languages and/or originatin ...

port A port is a maritime facility comprising one or more wharves or loading areas, where ships load and discharge cargo and passengers. Although usually situated on a sea coast or estuary, ports can also be found far inland, such as Hamburg, Manch ...

s. In the beginning of the 1970s, the whole Trunk Coal Line ( Pl: Magistrala Węglowa), which was the main route for exporting Polish coal, had been

electrified Electrification is the process of powering by electricity and, in many contexts, the introduction of such power by changing over from an earlier power source. In the context of history of technology and economic development, electrification refe ...

. This situation caused an urgent need for suitable locomotives able to pull heavy freight trains. As a result,` negotiations with

Plzeň Plzeň (), also known in English and German as Pilsen (), is a city in the Czech Republic. It is the Statutory city (Czech Republic), fourth most populous city in the Czech Republic with about 188,000 inhabitants. It is located about west of P ...

started. Poland sent an order for 60 articulated freight locomotives, based on the EU05, which was currently in service at the time. As of 2007, ET40 locomotives work mostly for

Bydgoszcz Bydgoszcz is a city in northern Poland and the largest city in the historical region of Kuyavia. Straddling the confluence of the Vistula River and its bank (geography), left-bank tributary, the Brda (river), Brda, the strategic location of Byd ...

engine shed A motive power depot (MPD) or locomotive depot, or traction maintenance depot (TMD), is where locomotives are usually housed, repaired and maintained. They were originally known as "running sheds", "engine sheds" or just "sheds". Facilit ...

, but in 2000 several units were sent to

Wrocław Wrocław is a city in southwestern Poland, and the capital of the Lower Silesian Voivodeship. It is the largest city and historical capital of the region of Silesia. It lies on the banks of the Oder River in the Silesian Lowlands of Central Eu ...

in order to serve on the highland Wrocław-

Jelenia Góra Jelenia Góra (; ; ) is a historic city in southwestern Poland, within the historical region of Lower Silesia. Jelenia Góra is situated in the Lower Silesian Voivodeship, close to the Karkonosze mountain range running along the Polish-Czech bo ...

line, where they are intended to replace

ET21 ET21 (also manufactured as Pafawag 3E) is a name for a Polish electric freight locomotive produced between years 1957 to 1971 in Pafawag. It was the first post-war Polish electric locomotive, designed in 1955. Besides being delivered for PKP, ET21 ...

locomotives.

Further innovations

One locomotive from the series - ET40-41 was rebuilt in 1990 into EP40 standard for high-speed passenger trains (up to 160 km/h), but as the result was not satisfactory, PKP resigned from further modernisations and the only EP40 was rebuilt back to ET40 standard in 1993.

Technical data

As a development of EU05 locomotive the ET40 technical features are in many ways similar to its predecessor, this refers mostly to the electric installation. The main differences are in the

transmission Transmission or transmit may refer to: Science and technology * Power transmission ** Electric power transmission ** Transmission (mechanical device), technology that allows controlled application of power *** Automatic transmission *** Manual tra ...

and cooling system. The locomotive consists of two mechanically and electrically identical sections. Each part has a crew compartment on one end and doors on the other, which enable moving between sections. It is possible to drive sections separately after they have been disconnected. Sections are distinguished by an additional letter A and B added to the locomotive's designation. ET40 is a

locomotive, meaning it is an articulated engine with two cabs fixed to the

frames A frame is often a structural system that supports other components of a physical construction and/or steel frame that limits the construction's extent. Frame and FRAME may also refer to: Physical objects In building construction *Framing (con ...

placed on two

bogie A bogie ( ) (or truck in North American English) comprises two or more Wheelset (rail transport), wheelsets (two Railroad wheel, wheels on an axle), in a frame, attached under a vehicle by a pivot. Bogies take various forms in various modes ...

s. Each bogie has two driving axles and each axle is propelled separately by 7AL-484ZT

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

with 510 kW constant power. Its parameters allow the machine to pull freight trains of approximately 4,000 t. weight. Crew compartments provide convenient driving of the machine in both directions. Entrance is possible through the doors on both sides of the locomotive. Crew compartments are heated with a fan powered electrically;

windscreen The windshield (American English and Canadian English) or windscreen (Commonwealth English) of an aircraft, car, bus, motorbike, truck, train, boat or streetcar is the front window, which provides visibility while protecting occupants from t ...

s are equipped with de-freezers and wipers. On the rear side of the crew section a locker for clothes and electric devices is mounted. Entry to the mechanical compartment is possible through two doors. The right one leads to

high voltage High voltage electricity refers to electrical potential large enough to cause injury or damage. In certain industries, ''high voltage'' refers to voltage above a certain threshold. Equipment and conductors that carry high voltage warrant sp ...

section, whilst the left provide access to the other crew compartment through a corridor running along the whole locomotive. The mechanical compartment is divided into three parts. Auxiliary fixtures, like

s cooling systems,

resistor A resistor is a passive two-terminal electronic component that implements electrical resistance as a circuit element. In electronic circuits, resistors are used to reduce current flow, adjust signal levels, to divide voltages, bias active e ...

s and main

compressor A compressor is a mechanical device that increases the pressure of a gas by reducing its volume. An air compressor is a specific type of gas compressor. Many compressors can be staged, that is, the gas is compressed several times in steps o ...

are located in the rear part of the section.

Refrigerator A refrigerator, commonly shortened to fridge, is a commercial and home appliance consisting of a thermal insulation, thermally insulated compartment and a heat pump (mechanical, electronic or chemical) that transfers heat from its inside to ...

washbasin A sink (also known as ''basin'' in the United Kingdom, UK) is a bowl-shaped plumbing fixture for washing hands, dishwashing, and other purposes. Sinks have a Tap (valve), tap (faucet) that supplies hot and cold water and may include a spray (l ...

and

cooker Cooker may refer to several types of cooking appliances and devices used for cooking foods. Types * AGA cooker – a heat storage stove and cooker, which works on the principle that a heavy frame made from cast iron components can absorb heat ...

occupied the front part of the corridor. The ET40 locomotive is equipped with an electro-

pneumatic Pneumatics (from Greek 'wind, breath') is the use of gas or pressurized air in mechanical systems. Pneumatic systems used in Industrial sector, industry are commonly powered by compressed air or compressed inert gases. A centrally located a ...

device to level otherwise unequal load on the track. The machine is equipped with two pneumatic

brake A brake is a machine, mechanical device that inhibits motion by absorbing energy from a moving system. It is used for Acceleration, slowing or stopping a moving vehicle, wheel, axle, or to prevent its motion, most often accomplished by means of ...

s - one automatic Oerlikon and additionally, braking only one section. Locomotives numbered from 01 to 30 had one

pantograph A pantograph (, from their original use for copying writing) is a Linkage (mechanical), mechanical linkage connected in a manner based on parallelograms so that the movement of one pen, in tracing an image, produces identical movements in a se ...

per section, whilst those numbered from 31 to 60 had two pantographs per section. Traction motors are connected with a

series connection Two-terminal components and electrical networks can be connected in series or parallel. The resulting electrical network will have two terminals, and itself can participate in a series or parallel topology. Whether a two-terminal "object" is ...

with voltage for each motor being 1500 V. They are cooled by two fans (one fan for two engines) with the air supplied by two intakes in the roof of the locomotive. Air for braking systems is provided by two compressors (one for each section) with nominal power of 140 m³/h.

Nicknames

*Bombowiec (''The Bomber'') *Bomba (''The Bomb'')

References

{{DEFAULTSORT:Pkp Class Et40 Škoda locomotives Bo′Bo′+Bo′Bo′ locomotives 3000 V DC locomotives Railway locomotives introduced in 1975 Polish State Railways electric locomotives Standard-gauge locomotives of Poland Freight locomotives