EMD DDA40X
| UP DDA40X "Centennial" | |
|---|---|
 6915 in Pomona Fairplex, Pomona (California, USA)
|
|
| Numbering: | 6900-6946 |
| Number: | 47 |
| Manufacturer: | EMD |
| Year of construction (s): | 1969-1971 |
| Axis formula : | Do 'Do' |
| Gauge : | 1435 mm ( standard gauge ) |
| Length over coupling: | 29,997 mm |
| Height: | 4,980 mm |
| Width: | 3,150 mm |
| Service mass: | 257.4 t |
| Wheel set mass : | approx. 31 t |
| Top speed: | 144 km / h |
| Installed capacity: | 6,690 hp (4,920 kW) |
| Starting tractive effort: | 596 kN |
| Driving wheel diameter: | 1016 mm |
| Fuel supply: | 31,151 liters of diesel |
| Motor type: | 16-645E3A |
| Motor type: | 2 × 16-cylinder V-engine with exhaust gas turbocharger |
The EMD DDA40X was a heavy diesel locomotive operated by the Union Pacific Railroad . Between June 1969 and September 1971 were 47 locomotives from General Motors Electro-Motive Division in La Grange , Illinois built. They were given the numbers 6900 to 6946.
Construction and technology
The locomotive was intended for use in front of heavy freight trains on the mountain routes of the Union Pacific, which previously had to be mastered with up to eight locomotives traveling in multiple traction. In the summer of 1965, the company had already gained experience with the DD35A , which basically consisted of two GP35 locomotives mounted on a frame . When the centenary of the first transcontinental railroad was approaching in 1969, the board decided to have a special locomotive built for the occasion. It should be the largest and most powerful diesel locomotive in the world.
The DDA40X is based on the use of the technical equipment of two GP40 locomotives in a single locomotive body , which is supported on two four-axle bogies . The locomotive was provided with a single cab at the end. It is driven by eight electrical traction motors suspended , the power was two 16 cylinder - diesel engines (hp per 3345) with flange-mounted alternator generated. The electricity produced was silicon - diode rectified, this technique has been applied to the DDA40 for the first time and found later, as well as many other new features, moving into other diesel-electric locomotive series.
Operational use
The first locomotive was handed over to the Union Pacific in April 1969, just in time for the anniversary celebrations, where it pulled the special train "Golden Spike". The other 46 machines were delivered by September 1971. The machines were mostly used in front of high-speed freight trains until 1980, when the freight volume declined in the early 1980s, they were taken out of active service and mothballed. In March 1984, 25 machines were reactivated, as larger transport capacities were required as the American economy grew. At the end of 1986 the machines were finally decommissioned.
Preserved machines
Of the original 47 locomotives, 13 vehicles have been preserved to this day, mostly in railway museums . One machine (6936) is still in working order and is used by the Union Pacific Heritage Fleet for special trips.
Web links
- Overview of the museum machines (english)