CPR class T4a
| CPR T4a | |
|---|---|
 Factory picture
|
|
| Numbering: | 8000 |
| Number: | 1 |
| Manufacturer: | Angus Shops , Montreal |
| Year of construction (s): | 1931 |
| Retirement: | 1940 |
| Type : | 1'E2 'hv3 |
| Gauge : | 1435 mm ( standard gauge ) |
| Length: | 30.1 m |
| Height: | 4.7 m |
| Width: | 3.1 m |
| Service mass: | 224.5 t |
| Service mass with tender: | 361.2 t |
| Starting tractive effort: | 400 kN |
| Coupling wheel diameter: | 1600 mm |
| Control type : | Heusinger control |
| Number of cylinders: | 3 |
| HD cylinder diameter: | 393 mm (15 ½ '') |
| LP cylinder diameter: | 610 mm (24``) |
| Piston stroke: | HD cylinder: 711 mm (28``) LP cylinder: |
| Boiler : | Schmidt-Henschel boiler |
| Cup length: | 5.8 m |
| Boiler overpressure: | Primary circuit: 90 bar Secondary circuit: 60 bar Long tank: 17 bar |
| Number of heating pipes: | 214 × 3.5 '' |
| Grate area: | 7.15 m² |
| Radiant heating surface: | 48.3 m³ |
| Tubular heating surface: | Schmidt boiler: 70 m³ Long boiler: 348 m³ |
| Service weight of the tender: | 137 t |
| Water supply: | 45 m³ |
| Fuel supply: | 15.5 m³ of oil |
The class T4a of the Canadian Pacific Railway (CPR) consisted of a single built for experimental purposes high pressure locomotive . Like the Selkirk locomotives, it was intended for use on the transcontinental route through the Rocky Mountains . The Texas locomotives had a 1'E2 ' wheel arrangement, i.e. a leading running axle , five coupling axles and a trailing bogie . The locomotive was built in the railroad's Angus Shops in Montreal . It is considered to be the largest high-pressure locomotive ever built and, without a booster, had the highest starting tractive effort of all CPR locomotives.
history
The design came from Henry Blane Bowen, a native of England and since 1928 chief engineer for train conveyance of the CPR. In the search for a more economical steam locomotive, in cooperation with Alco, the plans for a high-pressure locomotive emerged in 1929 , which was also to become the longest and heaviest locomotive built for CPR. The Superheater Company contributed superheaters and water tube boilers based on the patents of the German engineer Wilhelm Schmidt .
The locomotive was built in the railway's own workshops at the beginning of the Great Depression and delivered in May 1931. In October 1931, the locomotive was transferred cold on a freight train to British Columbia because there was no possibility of storing oil between Montreal and Calgary. In the Rocky Mountains , the locomotive was used in front of freight trains on the difficult section between Field and Revelstoke . Although the new locomotive saved a quarter of fuel and water, it was not a success. It was too delicate and complicated to operate for the drivers who were not sufficiently trained in this special design. In addition, many train drivers and stokers were afraid of the high boiler pressures that they would not show up for work when they were assigned to the 8000.
The locomotive also stood for repairs in the Calgary workshop for 17 months during its four years of service . The high pressure pump , which pressed the water from the long boiler into the secondary circuit of the Schmidt boiler, caused the most problems . With the technology of that time it was not yet possible to build reliable seals for pressures up to 60 bar. In addition, the mechanical expertise around this locomotive was only available in Montreal, which is more than 3000 km away.
In September 1936, the locomotive was withdrawn from scheduled service and transferred to Montreal. First the locomotive should be overhauled, but then doubts came. The locomotive was scrapped in late 1936 and scrapped in late 1940.
technology
The locomotive was equipped with a Schmidt-Henschel boiler . This water tube boiler consisted of a closed primary circuit filled with distilled water which was used to generate the high pressure steam in an open secondary circuit. The arrangement was intended to prevent the formation of scale in the tubular boiler, because the evaporation did not take place inside the pipes, but in an evaporation drum above the fire box.
The locomotive had three cylinders - a single high pressure cylinder located between the wheels and two external low pressure cylinders. The closed primary circuit of the Schmidt boiler had a pressure of 90 bar, the secondary circuit had a pressure of 60 bar and the live steam generated in the long boiler had a pressure of 17 bar.
The high pressure cylinder was supplied with the steam from the secondary circuit of the Schmidt boiler. The exhaust steam was fed to the two low-pressure cylinders together with the live steam from the long boiler.
Web links
Individual evidence
- ↑ Experimental Locomotives . Part 2. In: Railway Wonders of the World . December 6, 1935, p. 1413-1415 (English, html ).
- ↑ a b Jonathan Hanna: In the steam era, bigger was not always better . In: Steel Wheels . Summer, 2006 (English, html ).
- ↑ a b c d Super-powered rail engine's history is not that stellar. In: Moose Jaw Times Herald. September 24, 2010, accessed October 19, 2018 .
- ↑ T4a 2-10-4 Selkirk. In: Old Time Trains. Retrieved October 19, 2018 .