DK4
| DK4 | |
|---|---|
A DK4 converted to Korean State Railway operation, fitted with a pantograph. The wraparound windows have been replaced with simpler, flat windows and 2 out of 4 headlights have been removed | |
| In service | 1973– |
| Manufacturer | Changchun Railway Vehicles |
| Constructed | 1970s |
| Number built | 112 |
| Successor | BVG Class D |
| Formation | 1972–1990s Mc+Mc-Mc, Mc+Mc 1990s onwards Mc-Mc+M+Mc |
| Fleet numbers | 001-112 (original) 200s (later built non-driving trailers) |
| Capacity | 60 seated, 120 standing (not including 20% overload) |
| Operators | Pyongyang Metro Korean State Railway |
| Depots | Sopo depot |
| Lines served | Chollima Line, Hyoksin Line |
| Specifications | |
| Train length | 39,040 mm (128 ft 1 in) (two car) |
| Car length | 19,000 mm (62 ft 4 in) |
| Width | 2,650 mm (8 ft 8 in) |
| Height | 3,587 mm (11 ft 9.2 in) |
| Doors | 3 doors on each side, 1,200 mm (3 ft 11 in) wide |
| Wheel diameter | 840 mm (2 ft 9 in) |
| Maximum speed | 80 kilometres per hour (50 mph) |
| Weight | 34,500 kg (76,100 lb) |
| Axle load | 20.5 tons |
| Traction system | Variable camshaft resistor |
| Traction motors | ZQ76-3 |
| Tractive effort | 304 kW (one hour) 280 kW (longer periods) |
| Acceleration | 0.9 ms−2 |
| Deceleration | 1 ms−2 (service) 1.3 ms−2 (emergency) |
| Power supply | 110 volts |
| HVAC | 220V single-phase AC powered ventilation |
| Electric system(s) | 750 volts (+20%, -35%) |
| Current collector(s) | Third rail, top contact In State Railway service: pantograph |
| AAR wheel arrangement | 20–20 |
| Braking system(s) | resistor braking, electro-pneumatic brake, hydraulic brake |
| Coupling system | Scharfenburg |
| Headlight type | 220V AC lighting |
| Track gauge | 1,435 mm (4 ft 8+1⁄2 in) |
| Notes/references | |
The DK4 are a class of electrical multiple units built by Changchun Railway Vehicles, operated on the Pyongyang Metro, and later the Korean State Railway. The sets developed in parallel with the DK3, and these sets were delivered new to the Pyongyang Metro when it opened in September 1973, although they have since almost entirely disappeared from the metro network, with many sets being converted to be used under overhead catenary as electric multiple units, or as a locomotive.