The largest and most powerful locomotive of its kind in the world and the first of the type in America was completed and ready for service when the giant, oil-burning, three cylinder “8000” type engine, representing a new era in the advancement of steam motive power of greater efficiency and higher sustained capacity, was placed on exhibition in the Windsor Street station of the Canadian Pacific Railway at Montreal recently. It was built by the railway at its Angus Shops in Montreal and is destined for use in freight and passenger service in the Rockies, It is attracting much interest in mechanical and railroad circles, particularly because of the radical departure in boiler design from the present type of locomotive boiler, and also because of the high steam pressures used with resultant economies in fuel without additional costs for boiler maintenance.

Particulars of the Locomotive.

Statistics in regard to this monster locomotive will give some idea of its size. The weight of the engine is 485,000lbs. and the tender 300,000lbs”, a total of 785,000lbs. or 3921/2 tons, while length overall of the two is 99 feet 3 3-8 inches, an increase in weight of 44,800lbs. and an added length of 1 foot two inches over the “5900” series locomotive, the biggest locomotive prior to the construction of the “8000.” The ten driving wheels are 63 inches in diameter, the two low-pressure cylinders located outside the frame and using superheated steam at 250lbs. pressure per square inch are 24 inches in diameter by 30 inches, stroke. The high-pressure cylinder situated between the frame and using superheated steam at 850lbs. pressure per square inch is 151/2 inches in diameter by 28 inches stroke, transmitting its power through a piston and connecting rod to a crank axle located at the second pair of driving wheels. The tractive effort of the locomotive is 90,000lbs., an increase of about 17,000lbs. over the “5900” series. This means that on a level track the “8000” will be able to haul a freight train of 150 forty-ton freight cars, a total weight of 6000 tons and over a mile in length. The tender has a capacity of 12,000 gallons of water and 4350 gallons of fuel oil, enabling the locomotive to make long hauls without replenishing. The aggregate length of all the seamless steel tubes used in the construction of the boiler units alone totals to 18,695 feet or slightly over 31/2 miles.

The “8000” is termed a “multi-pressure” locomotive because steam is generated in three separated portions and at three different pressures. The firebox and combustion chamber are formed by tubes in which steam at 1300 or 1350lbs. pressure per square inch is generated from distilled water. The water in this system, heated by the furnace gases, is converted into steam which passes through coils located inside the highpressure page 35 drum. The heat from this steam passes through the walls of these tubular coils and is absorbed by the water in the high-pressure drum. The condensate flows downwards to the bottom of the firebox, and is again re-circulated through tubes without loss. The water in the high-pressure drum is heated, as described above, and is converted into steam at 850lbs. pressure. From the high-pressure drum this steam passes through a type “E” superheater, an “MV” throttle and to the high-pressure cylinder. The low-pressure boiler, which resembles the barrel portion of the conventional locomotive boiler, generates steam at 250lbs. pressure per square inch. This steam flows through a second type “E” superheater, an “MV” throttle and into steam pipes which join the exhaust steam pipes from the high-pressure cylinder. The steam exhausted from the high-pressure cylinder joins with the steam from the low-pressure boiler and flows to two low-pressure cylinders located in the normal position.

The firebox unit is designed for 1700lbs. pressure per square inch with an average working pressure of about 1350lbs.

Wonder Trails of the “Iron Horse.”
(Photo, courtesy Mr. S. Fahey, Featherstott.)
The electric metre-gauge line of the Rhaetian Railway on the Coire-St. Moritz route, in the Canton of the Grisons, Switzerland. The illustration shews how the engineers solved the difficulty of overcoming a difference in altitude of 1,335 feet, between. Bergun and Preda, by the construction of three spiral tunnels. On the extreme right is shewn the portal of Zuondra Tunnel, and just above, the continuation of the line to Preda; in the middle centre is shewn the portal of Toua Tunnel, its exit appearing just, below the viaduct in the middle foreground, thus completing a double-spiral In the left background, the third spiral is shewn. The portal of Rugnux Tunnel is entered just after crossing the viaduct, and after making the complete spiral the line emerges on to the viaduct shewn below and to the right of the uppermost viaduct. An unusual feature of these spiral tunnels is that they complete the entire spiral circle, within the heart of the mountains.

This unit is really a closed circuit containing approximately 300 gallons of distilled water. The use of distilled water is to prevent the accumulation of sludge and scale so common in water tube boilers. The closed circuit or firebox unit extends into the high-pressure boiler drum in the form of 16 coils, called heat transfer coils.

There are three locomotives of this type in Europe which are showing excellent savings in fuel, ranging from 25 to 35 per cent. in comparison with the conventional design of locomotive. The largest of the European locomotives is only 42 per cent, of the weight and develops 36 per cent, of the power of the “8000.”

In co-operation with the American Locomotive Company and the super-heater Company, of New York, H. B. Bowen, Chief of Motive Power and Rolling Stock, Canadian Pacific Railway, designed the “8000” after he had made a special trip to Europe in 1929 for the purpose of studying various types and developments of locomotives there. The construction of this giant locomotive was handled under the direct supervision of J. Burns, Works Manager, Angus Shops, and T. Donald, of Mr. Bowen's staff.