PKP class EU06

EU06 (also manufactured as AEI E) is a class of electric locomotives in service with the Polish state railway PKP.

EU06 has driving cabs at both ends. The locomotives are equipped for multiple working which allows one driver to drive two coupled engines from one cab. One locomotive can haul passenger trains of up to 650 tonnes (640 long tons; 720 short tons) at 125 kilometres per hour (78 mph) and freight trains of up to 2,000 tonnes (2,000 long tons; 2,200 short tons) at a speed of 70 kilometres per hour (43 mph).^{[citation needed]} Two locomotives coupled in multiple can haul a freight train of up to 3,600 tonnes (3,500 long tons; 4,000 short tons).^{[citation needed]} These figures apply to driving on level gradients.

All members and panels are made of Cor-Ten steel and the underframe is a shallow, cellular structure with closely spaced light-gauge longitudinal and transverse members plated above and below to make a set of closed cells.

The body sides are built up on rectangular vertical tubes forming a set of pillars and are double-skinned for additional strength and rigidity. This maintains the shape of the locomotive allowing the roof of the entire machine space between the two cabs to be removed to allow machinery to be lifted out and replaced. The superstructure is built to withstand buffing loads up to 295 long tons (300 t; 330 short tons). English Electric made extensive use of aluminium alloys and GRP for panelling, doors and ducts.

Current collection is by single-pan air operated pantographs, which feed the main power circuits by a high-speed circuit breaker. The main resistances were made by Metropolitan-Vickers' parent company, Associated Electrical Industries. The four traction motors are permanently connected in series pairs, with series-parallel combinations between pairs. Parallel and 12 field weakening positions give a total of 55 running notches. The four traction motors have Alstom quill drives.

The minimum curve radius that the locomotives can negotiate is 6 chains (396 ft; 121 m): any curve tighter than this could cause severe flange wear on the wheels. In order to reduce flange forces, the bogies are linked by a tubular-framed spring-loaded inter-coupling and flange lubricators are fitted to each wheel.

In 1936–1938 the Contractors' Committee, a joint venture of Metropolitan-Vickers and English Electric, had supplied six 1,200 brake horsepower (890 kW) electric locomotives and 80 three-car electric multiple units for the electrification of Warsaw suburban services. British Insulated Cables supplied the overhead line equipment. In 1945 British Insulated merged with a competitor to become British Insulated Callender's Cables, and in 1949 Metropolitan-Vickers, English Electric and BICC contracts to replace locomotives, EMUs and equipment damaged in the Second World War.

In the early 1950s PKP urgently wanted mixed-traffic electric locomotives for the rapid electrification of Poland's railways. ET21 freight locomotives were already in production but there was a lack of passenger locomotives. The plan was to buy several items of foreign-built locomotives and a license and start domestic production afterwards.