1940: Railroad Equipment

The year 1940 has been unprecedented in the number of streamlined trains that have been placed in service in the country, there being a total addition of 32 trains and 203 cars. Moreover, there are also on order 26 more of such trains and coincidentally 203 cars, the same number as for 1940. This increase in streamliners is due to the fact that existing streamliners have shown splendid earnings. In both railway cars and Pullman cars the comforts have been greatly increased and the interior designs have become even more attractive. Fluorescent lighting now prevails in most of the later car designs. In fact, a 6-watt, 9-inch lamp has been designed particularly for Pullman berths and airliners. The effect of the railroads' efforts, begun just a short time ago, to attract the public back to rail travel, although belated, is now bearing fruit.

In the earlier days of streamliners the trains were 'fixed,' that is, cars could not be added by a mere switching operation. However, the use of such trains became so popular it was found that the inability to provide flexibility incident to the sudden demands that frequently occurred was a distinct disadvantage, so that now with most trains cars can be added easily when the occasion demands it. Moreover, in the construction of cars, the design is towards light weight commensurate with rigidity and safety. The cost of operation, both as regards motive power and maintenance of rolling stock, and rails, is greatly diminished with reduction in weight.

The Pennsylvania railroad increased its motor power equipment by the addition of twenty streamlined electric locomotives constructed in its Altoona Shops, the electrical equipment being supplied by the General Electric Co. These locomotives are now used in handling the high-speed passenger transportation between New York and Washington and operate on daily schedules exceeding 60 miles per hour between terminals.

The electrification of this railroad now involves nearly 2,200 miles of electrified tracks and more than 200 electric locomotives, and stands out as one of the foremost electrification installations in the world.

New Electric Locomotives.

The four most powerful dc passenger electric locomotives ever built were completed during the year by the General Electric Co. for the Paulista Railway in Brazil. Each unit weighs 185 tons, has a nominal rating of 4,050 horsepower in continuous service and 4,420 horsepower on an hourly basis. This is the largest continuous rating in a single cab direct-current locomotive ever built in the United States up to date. These locomotives give a maximum speed of 93 miles per hour. On a 2 per cent grade the locomotive will handle a 1,000-ton train at 50 miles per hour. The motive power consists of six-series traction motors of the force ventilated type, each designed for 1500-volt dc operation and designed to operate two in series at 3,000 volts dc. Power is collected from a 3,000-volt overhead trolley by two air-raised, gravity-lowered pantographs equipped with two contact shoes each, the two pantographs working independently. There is a three-speed system of control which gives motor combinations of six in series (lowest speed); three in series, two groups in parallel (intermediate speed); and two in series, three groups in parallel (maximum speed).

Regenerative Braking.

Since there are many grades on the road, regenerative braking is highly desirable. In regenerative braking the traction motors are connected to operate as generators and the energy of the moving train is converted into electrical energy and pumped back into the trolley system. Another important advantage of regenerative braking is the saving of wear and overheating of the brake shoes. Series motors such as are used on electric locomotives will not, of themselves, operate satisfactorily to return power to the line, on account of their electrical characteristics. However, by exciting their fields by an independent low-voltage motor-generator set on the locomotive, very satisfactory regeneration is obtained.

The Paulista Railroad has increased its electrification to 178 route miles and 350 track miles. It now has 49 electric locomotives.

Diesel-Driven Units.

The year 1940 has probably seen the greatest annual increase to date in Diesel engine motive-power traction units, both in the locomotive and in unit plants in cars. The Diesel engine is in many cases operated to drive through a clutch mechanism and it is also used in connection with an electric drive.

Diesel-Electric Freight Locomotive.

There has been considerable interest in the performance of the new Diesel-electric locomotive manufactured by the Electro-Motive Co. and proportioned for freight service. Data from its performance are awaited to determine the place which it may be expected to assume during the coming era of higher freight-train speeds. The locomotive is made up of two two-unit locomotives, each unit of which is carried on two four-wheel trucks and driven by a General Motors Diesel-electric power plant. The two locomotives coupled back to back make a multiple unit locomotive of 5,400 engine horsepower which weighs about 912,000 lb. and is 193 ft. long over the coupler pulling faces. With all the weight on the driving wheels, the starting tractive force is 228,000 lb. The maximum speed is 75 miles per hour.

It is interesting to compare the Diesel-electric locomotive with the steam locomotive as regards starting and running performance since such performance characteristics are highly important in determining its adaptability to freight service where high tractive effort, ability to perform switching operations readily, and high speed are all necessary. The Diesel-electric is essentially a constant horsepower machine and accordingly develops a high ratio of tractive force to rated horsepower capacity, whereas the steam locomotive, which develops its maximum horsepower rating at relatively high speeds has a low ratio of tractive force to rated horsepower capacity. For example, with the Diesel-electric the ratio of starting tractive force to maximum drawbar horsepower is almost 52.8 whereas that for the steam locomotive is only 17, which can be raised to 20 by means of a booster. Accordingly, if the freight trains require sufficient horsepower to operate from 40 to 60 miles per hour, the Diesel-electric would have ample capacity to start the train, whereas the steam locomotive might require assistance. Moreover, it follows that the Diesel-electric locomotive is far better adapted to switching duty than the steam locomotive. At lesser speeds than 40 miles per hour the Diesel-electric would accelerate more rapidly than the steam locomotive. The steam locomotive would probably prove advantageous on long grades with heavy trains, which tend to cause overheating of the electric equipment in the Diesel-electric locomotive. There has not as yet been opportunity to make an extended comparison of the performance of this new Diesel-electric locomotive with its steam counterpart. The results are awaited with interest and will be reported when available.

Puerto Mexico-Campeche Railroad.

Mexico has just completed a new railroad 460 miles long from Puerto Mexico to Campeche, Yucatan, and it is interesting to note that after careful consideration Diesel-electric locomotives have been selected as being best adapted to the service. The route lies through subtropical country where water is at a premium so that steam-locomotive operation would be difficult. The line is a low-grade one, the maximum grade being 1.35 per cent.

At present only two locomotives have been delivered. These are ultimately intended for switching service but are now hauling work trains and other trains. Each is of a semi-streamlined design, having a Cooper-Bessemer 500-hp., 7500 rpm, 4-cycle, 6-cylinder Diesel engine directly connected to a General Electric generator. The motors are series-wound traction motors having a rating of 108 horsepower each. The locomotive weighs 130,000 lb. and has a continuous tractive effort of 17,900 lb. at 8 miles per hour. A 56-cell Exide Ironclad battery for starting and control is charged while the engine is idling.

The first Diesel electric passenger locomotive to be built by the American Locomotive Co. was delivered to the Chicago, Rock Island & Pacific Railroad where it is being used on the road's 'Rocket' trains. This locomotive is equipped with two 1,000-hp. MacIntosh & Seymour six-cylinder four-cycle vertical engines.

Other Diesel-electric locomotives used to drive the Rockets have two 1,000-horsepower, V-type, twelve cylinder, two-cycle engines.

Self-Contained Diesel-Driven Cars.

The year 1940 has seen a rapid increase in the use of the self-contained Diesel-engine or similar oil-fuel motive power plant for use on individual cars. Two types of drive are embodied, the use of an electric generator driven by the engine, the generator supplying the direct current to series-connected driving motors; and the use of some form of hydraulic clutch combined with gears for the transmission of the mechanical power to the wheels. The use of the mechanical drive has been made possible by the recent development in the automotive field of the highly efficient hydraulic clutch or, as it is called in traction work, a hydraulic torque converter. This hydraulic torque converter absorbs engine vibration and shock loads, permits smooth starting and gives different ratios of engine to driving-wheel speed.

The advantage of the unit car is the flexibility, permitting frequent and fast passenger service with minimum cost and weight of equipment. Moreover, when conditions require it, provision may be made whereby the individual cars can be made into trains as is described later.

Of particular interest are the two cars of new design recently completed by the American Car and Foundry Co. for fast passenger service. One of these cars, the Illini, is in service on the Illinois Central between Chicago and Champaign. The other, Miss Lou, will operate between Jackson, Mississippi, and New Orleans, La. The Illini covers the 183-mile run from Chicago to Champaign in exactly four hours, with 16 stops, with an average speed of 45.8 mi. per hour. The overall length is 72 feet and the seating capacity is 69 and the light weight on the rails is 85,300 lbs. Low-alloy, high tensile steels are used throughout for the framing or strength members. The power plant consists of two six-cylinder Waukesha-Hesselman 225-horsepower oil engines with a twin disc clutch and torque converter. Although the engines burn Diesel oil they are not Diesel engines but are solid injection, low-pressure (150 lb.) electric-ignition oil engines. The engine, like the Diesel, draws in a charge of air alone, which is then compressed to a maximum compression of 140 lb. per sq. in. Near the top of the compression a measured charge of fuel oil is injected by a fuel pump into the turbulent air and the charge is ignited by a spark plug.

Each engine develops 225 hp. at 1800 rpm. Each will operate independently or together from one control station permitting flexibility in car performance.

The transmission is a hydraulic torque converter which includes a direct mechanical-drive feature. In one position of the control handle the speed may be brought up gradually to 45.8 miles per hour while in a second position of the control handle the speed is increased to 73.5 miles per hour, direct mechanical drive then being used.

Similar cars, also built by the American Car & Foundry Co., have been put in service by the New York, Susquehanna & Western R.R. for the service of commuters in the New Jersey metropolitan area. The cars are 76 feet long, being designed for 80 passengers, and the weight on the rails is 73,500 pounds. The cars are made of United States Steel Co. Cor-Ten steel and are both spot welded and riveted. Aluminum alloys are used for interior finish. These cars are also driven by a Waukesha supercharged engine using Diesel fuel with spark plugs. The engine is rated at 290 horsepower and the maximum governed speed is 1800 rpm. A hydraulic torque converter is used for transmission of power from the engine to the wheels.

The Chicago, Burlington and Quincy Railroad has extended the unit car to a 4-car train, the General Pershing. In each passenger car there is a 69-horsepower Diesel engine, direct-connected to 30-kilowatt generators mounted under the car. The engine and generator supply heating, cooling, lighting and all auxiliary requirements, making each car a completely independent unit. Heat is derived not only from the generator output but also from the engine cooling water.

It is notable that railroad engineers continue to follow automobile practice in the increasing use of the mechanical disc and rotor-type brakes. This relieves or eliminates braking from the rims of the wheels.