GN class Z1
| Great Northern Railway Z-1 | |
|---|---|
_(14574492017).jpg) Z-1 No. 5004 and 5005
|
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| Numbering: | 5004-5013 |
| Number: | 10 (5 double locomotives ) |
| Manufacturer: | Baldwin Locomotive Works , Westinghouse Electric |
| Year of construction (s): | 1926-1928 |
| Retirement: | 1956 |
| Axis formula : | 1'Th 1 ' |
| Gauge : | Standard gauge (1,435 mm ) |
| Service mass: | 168 t |
| Hourly output : | 1,614 kW |
| Continuous output : | 1,365 kW (1,830 hp ) |
| Continuous tensile force: | 393 kN |
| Power system : | 11 kV , 25 Hz |
| Power transmission: | Overhead line |
The class Z-1 of the Great Northern Railway comprised ten electric locomotives built by Baldwin and Westinghouse with the axle formula 1'Do 1 'for operation on the electrified railway line through the Cascade Tunnel .
history
Between 1925 and 1929, the Great Northern built a new 12.5 kilometer long Cascade Tunnel under Stevens Pass . Steam locomotives should also not be used in this tunnel due to the inadequate ventilation .
The entire electrified section between Wenatchee and Skykomish in Washington state was 117 km long. In contrast to the 6.6 kV 25 Hertz three-phase system previously used in the old tunnel, 11 kV 25 Hz single-phase alternating current was used in the new tunnel . This took over the experience from the successful tests with the same system on the Detroit, Toledo and Ironton Railroad . New locomotives also had to be purchased for use on the new tunnel route.
The first four locomotives were delivered in 1926. The mechanical part was made by Baldwin and the electrical part by Westinghouse. These locomotives were delivered as two permanently coupled double locomotives . Until 1946, the other locomotives were gradually connected in pairs to form double locomotives. Four locomotives were able to move a 2900-ton train over the 2.2% gradient.
The two double locomotives were initially given the numbers 5002A / B and 5007A / B, whereby the appended letter was used to distinguish the two halves of the locomotive. The other locomotives were given the numbers 5000–5001 and 5004–5007. After several redesignations, the locomotives that had meanwhile been combined into double locomotives were finally given the numbers 5000A / B, 5002A / B, 5004A / B, 5006A / B and 5008A / B.
After a more efficient ventilation system was installed in the tunnel, all locomotives were retired and scrapped in 1956.
technology
It was converters - locomotives , where the alternating current from the overhead line initially stepped down was and two AC motors drive. This in turn driven DC generators to which the four Westinghouse 356-A DC - traction motors supplied.
The locomotives had multiple controls and a regenerative brake .
literature
- William D. Middleton : When the steam railroads electrified . 2nd revised edition. Indiana University Press, Bloomington, IN 2001, ISBN 978-0-253-33979-9 (American English).
