PKP class ET22

ET22 (also manufactured as Pafawag 201E) is a Polish six-axle electric freight locomotive built by Pafawag from 1969 to 1989. Factory designation is 201E. With 1183 units, it is one of the most numerous standard gauge electric locomotive built in Europe. Further 23 units were built for Morocco as E-1000 class.

Soon after Pafawag started the production of the universal EU07 locomotive, The Rolling-stock Industry Central Bureau of Construction (Polish: Centralne Biuro Konstrukcyjne Przemysłu Taboru Kolejowego) began to develop a new heavy Co-Co freight locomotive. The electrical components of the locomotive, including the traction motors, were based on the equipment used in the EU07. The new locomotive had some modern features, including its body.

The first two prototypes of the class 201E were ready by the end of 1969 (ET22-001 and 002). A short series of ten was made in 1971, and large scale production started the following year. PKP bought 1183 locomotives until the production was ceased in 1989 (numbered ET22-001 to ET22-1183, including two 201Ec type), the last of which were delivered in 1990. This made the ET22 class the most numerous standard gauge electric locomotive built in Europe.

During the production the design of the ET22 locomotive was slightly altered. Some changes were also made during repair and maintenance.

The body of the locomotives in use is different from the prototypes in details. There are three basic types of locomotive bodies where the main differences are the size and placement of the side windows, air intakes and ventilation grids. From ET22-013 big grids on the left side for resistors' cooling were moved from upper part to lower part of the body. From ET22-242 air intakes for engines' cooling were moved from a roof edge to side walls, on both sides, which is most popular configuration.

From ET22-122 there was simplified and improved a suspension of the body, without transversal beams. From ET22-282, big headlights, typical for Polish railways, were fitted in conical covers instead of hexagonal.

In 1973 Pafawag built a prototype passenger locomotive of the building type 201Ea, which had a different gear ratio for top speed 160 km/h, with no other substantial changes. The locomotive was classified as EP23-001, being a sole machine of this class. After a series of tests, the locomotive characteristics were found unsatisfactory and no more were built. In 1979 the prototype was rebuilt to ET22 standard and renamed ET22-121 in place of former locomotive 121 scrapped in 1977. Today this locomotive is conserved in Jaworzyna Śląska railway museum.

Another two prototype locomotives were produced in 1978 as type 201Ec (also known as type 202E). Main changes introduced were an improved secondary suspension, multiple unit control and several small modernisations, like automatic door control. Wheelbase of bogies increased from 3,500 to 3,800 mm (11 to 12 ft) and they were connected with a linkage, but the overall wheelbase increased only by 80 mm (3.1 in). Those locomotives were first given the numbers 501 and 502. As the production of ET22 continued, those were renumbered to 701 and 702 and finally to 1001 and 1002, which they carried until the end. A modernization was considered successful, but in a view of an economical crisis in 1980s in Poland, the authorities of a planned economy lost interest in starting production of an improved locomotive.