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THE EVOLUTION OF ELECTRIC RAILWAYS In the space of about ten years or so, diesel electric locomotives completely displaced all the hundreds of thousands of tried and proven steam locomotives that had served well for one hundred and twenty years! Why? By BRYAN MAHER Herr Doktor Rudolph Diesel (Germany, 1858-1913), inventor of the internal combustion engine which now bears his name, envisaged a simpler and more efficient engine than the system pioneered by fellow German Karl Benz in 1878. The 76 SILICON CHIP diesel engine needs no electric spark nor carburettor, only a piston, cylinder, two valves and a pump to inject fuel oil under high pressure. When the piston has drawn air into the cylinder and compressed it to a high pressure and temperature, a small quantity of fuel oil is injected to cause self-combustion. This drives the piston down and turns the crankshaft. Herr Diesel originally intended his design for airplane propulsion but his first successful engine in 1897 was too heavy to fly. Consequently he turned his thoughts to diesel ship propulsion. His engine was more efficient than some of the reciprocating steam engines in shipping use at the time. Sadly his life was cut short, for he died in mysterious circumstances in 1913. After boarding a ship bound for England he apparently disappeared en route and was never seen again. It was before the outbreak of FACING PAGE - AMTRAK'S TURBOLINERS represent a blend of American and French design with their modern lines and comfortable interiors. Seven of these red, white and blue "turbos", built by Rohr Industries in California, are used on inter-city rail services. The photograph above shows an early NSW SRA diesel-electric passenger train. These trains were used on NSW country routes but have now given way to the recently introduced XPT. World War 1 and he might have been walking a political tightrope, as his 4-stroke diesel engine had potential for naval ship propulsion. The four "strokes" of his engine piston are air intake, air compression, power (fuel burning) and exhaust. Thus power is delivered on only one piston stroke out of each four; ie, one quarter of the time. Later Sir Dugald Clerk of England extended the diesel design to give one power stroke every time the piston travels downwards and one compression stroke on each upward movement; ie, one power stroke out of each two. This is called the "2-stroke" principle, which gives power one half of the time. Compared to a 4-stroke engine, the 2-stroke design gives more power for a given size and weight but its efficiency and fuel consumption may be greater or less depending on the construction. Since those days the diesel engine has pervaded every area of the transport industry, some ships today having engines so large that you would climb up two flights of stairs to go from the crankshaft floor to the cylinder head level. Their pistons can measure a metre in diameter and have a piston stroke of two metres. First diesel electric In 1913 the Mallesta and Sodermanlands Railway Company of Sweden made history as the first railway to use diesel electric propulsion regularly. But because diesel oil was scarce in Europe and hydro-electric power available, the Swedes retained their preference for electric railway traction. Today in Sweden there are only 533 diesel electric locomotives compared to 726 electric locomotives. But that little Swedish experi- ment did not go unnoticed on the other side of the world. In the USA the motor car and truck firm General Motors (GM to most people) had observed the advantages of diesel electric railroad propulsion and thought well ahead. We remember that in the period 1900 to 1930 the American steam locomotive had grown from 100 tonnes to over 500 tonnes, featuring designs with up to 24 driving wheels, such as the Erie Railroad's 2-8-8-8-2 monster built by the Baldwin Locomotive Works in 1914. The Mallet type loco itself weighed 384 tonnes and had an enormous tender carrying 37,850 litres of water (37.85 tonnes) and 16 tonnes of coal. This loco featured six steam cylinders each 91cm (3 feet) in diameter, working in compound with a boiler pressure of 1448 kilopascals (210psi). The tractive effort exerted was 72.7 tonnes. DECEMBER1988 77 AMTRAK'S "MINUTE MAN" HEADS for Boston on its way from Washington, near Warwick, Rhode Island. Although the Northeast Corridor is electrified between Washington and New Haven, diesel-electric locomotives are used the rest of the way to Boston. To ensure crew safety, the windscreen is bullet proof and can withstand the impact of a concrete block at speed. More powerful still was a 2-10-10-2 articulated steam locomotive built by Baldwin for the Virginian Railroad in 1918. Its largest cylinders were 1.22 metres (4 feet) in diameter and when all cylinders were fed with full steam pressure at 1483kPa (215psi) this locomotive produced a tractive effort of 79.38 tonnes (175,000lbs). Would you believe that it was the enormous power and tractive effort produced by these monster steam locos, the largest ever built, which produced the decline and death of the steam locomotive worldwide and the rise to dominance of the diesel electric locomotive? If you find that that strains credibility, consider if you will the following sequence of events. Single large locomotives American Railroads could be divided into the coal carriers (Virginian, Erie, Norfolk & Western, and 78 SILICON CHIP Chesapeake & Ohio Railroads) on the eastern side of the country and the long-haul freight carriers (Union Pacific, Santa Fe, etc) whose tracks crossed the western Rocky Mountains to the Pacific coast. The eastern coal carriers naturally leaned towards steam locos as coal and water were near at hand, tenders could be refilled often and their routes were not too long. All the eastern coal lines had to surmount the Appalachian and Allegheny mountains of Virginia and West Virginia on their way to the Atlantic Ocean export ports of Chesapeake Bay. Their monstrous locomotives single-handedly hauled coal trains of 7000 tonnes up the mountains on 1-in-62 grades and dragged 15,000 tonne trains on the coastal plains to the ports. But why not use two smaller locomotives in double-head mode? There were two reasons: (1) the difficulty in synchronising the starting of two huge steam locos; and (2) the cost of the extra loco crew of three (driver and two firemen). This led to the concentration on single huge locos. In contrast, the long-line freight railroads such as Union Pacific had to carry coal (and even water) thousands of kilometres to their locorefuelling points. In 1942, Santa Fe were hauling more than 200 large water tank wagons daily to quench the thirst of their steam locos running between Winslow, Arizona, through Flagstaff to Barstow, California. Thus in America the western Rocky Mountains were crossed by beautiful steam locomotives, each with a tender as big as a ship in tow. The 6000hp (4.5MW) "Big Boys", the largest Union Pacific steam locomotives, had a tender carrying 32 tonnes of coal and 110 tonnes of water. Two 16-wheel bogies were needed to support the nearly 200 tonnes of the tender. Australian inland railways had the same problem. Many a reader will remember outback steam passenger trains which included a large water tank truck immediately behind the loco tender. The Australian National Railways by necessity carried huge quantities of water between Port Pirie and Kalgoorlie. The classic steam loco used to cross the Nullarbor Plain was a copy of the NSW 36 class but with an oversize tender which weighed more than the loco! Such a line was ripe for the diesel electric salesmen! Enter diesel electrics Herr Doktor Diesel's first effort at rail traction in 1913 was a failure because he attempted direct drive from the engine to four coupled wheels. His 4-4-4 locomotive ran but was unpopular. The Swedish idea, pioneered by ASEA, used the diesel engine to drive a DC generator which powered electric traction motors, giving better control of speed and starting. By 1924 the first diesel electric loco appeared in the USA. Though only 300hp (334kW), this yard switching loco built by American General Electric Company was the beginning of an era. The world's first diesel electric loco for export was also produced in 1924 but it came not from the USA. It was an ASEA 200hp (149kW) Bo-Bo locomotive exported to Tunisia. It was a great success. In the same year both Austria and Germany were experimenting and Brown-Boveri/Fiat built a 440hp (328kW) diesel electric for service in Italy. In 1933 Germany had a diesel electric "Flying Hamburger" train running between Berlin and Hamburg. It covered the 285km in two hours eighteen minutes, averaging 123km/hour. Still, American railroads had steam hauled trains that ran faster. For example, the Santa Fe had to run some trains at 160km/hour to keep to timetable. So why did diesel electric traction demolish the steam locomotive? TWO POWERFUL CONRAIL Bo-Bo diesel electric locomotives are shown here hauling a heavy freight train. Each loco is an EMD Model GP9 weighing 114 tonnes and rated at 1.3MW (1700hp). The diesel engine is a 16-cylinder Model 567C which is direct-coupled to a DC generator. Cost comparisons Was the answer prime cost? No, not at all, for the big American manufacturers, like the Baldwin Locomotive Works, could turn out three steam locomotives per day, each costing only one third that of a diesel electric unit of equivalent power. Perhaps readers think that the cost of servicing a dirty steam locomotive for each 1000km run was more than the cost of keeping a diesel electric on the road? Not necessarily so. Many countries, including Australia, serviced their old steam locomotives in ancient, ill-equipped running shops. In 1940 it was still a practice at Eveleigh shops in NSW for candles to be used for illumination when lubricating the valve rods between mainframes in 50-class steam locos. Contrast that with the modern Norfolk & Western Railroad running shops in the USA which could service a 500 tonne giant steam locomotive and have it out on the road again in 50 minutes. And that included a complete clean, lubricate and refuel job, including cleaning inside the smokebox. It was entirely unrealistic for Australians in 1950 to compare the maintenance cost of a NSW 50-class steam freight locomotive, then 60 years old, with the 40-class diesel electric, in those days the latest thing on twelve wheels. The 40-class of 1650 hp (1.23MW) lasted about thirty years, about half the life of many steamers. A further complication arose with these diesel electrics: an instruction was issued that should they ever suffer a simple derailment, the diesel engine was to be stopped and not restarted until the maintenance workshop had stripped the engine down and tested the alignment of the long crankshaft! A more realistic comparison in 1950 would have been to compare diesel electrics with the newer 38-class steam locomotive. This was a beautiful machine, very fast, whisper quiet, powerful, and using local coal and water instead of imported diesel oil. No, maintenance costs were not the reason for the steamers' demise. To see why diesel electrics conquered the world, we must look at the biggest and most successful American steam locomotives. Efficiency and running cost Was it the inefficiency and running costs of steam? No, running cost was not the the reason. The Norfolk DECEMBER 1988 79 AMTRAK'S P-30CH DIESEL-ELECTRIC locomotives are built by General Electric for medium and long-haul routes. These powerful 6-axle Co-Co locomotives are rated at 2.24MW (3000hp), have a top speed of 165km/hr and weigh 176 tonnes. and Western Railway resisted the diesel electric demonstrations as late as 1960, showing that their very large modern steam locomotives could equal or outperform any diesel electric units on running costs alone. Those tests were conducted hauling equal train tonnage over the same tracks at equal timetable. The running costs (per tonne hauled) of the huge steam locos were so low simply because those locomotives were so big. One 3-man loco crew could haul any train of the day up any mountain. But competition between railroads being fast and fierce, there was continual striving for yet bigger locos to haul even longer heavier trains. And by the 1930s the design of large steam locos had reached the absolute practical limit. Any increase in steam loco power must mean higher steam 80 SILICON CHIP pressure. This in turn requires larger fire grate area or a larger boiler and cylinders. But the boiler and cylinders could not be increased further in diameter otherwise the locos would not fit through the tunnels. For the same reason, the height could not be increased. The American locos were already up to a metre taller than many Australian machines. Boiler problems No, the only boiler dimension which could be increased was the length. Such an increase could restrict running speed on curves but there is a more critical problem. An overly long boiler has trouble with its fire tubes which run the length of the boiler from the firebox to the smokebox at the front. If the boiler is too long the fire inside those tubes goes cold before reaching the front and boils no more water. So increased boiler length gains nothing. They just could not build larger steam locomotives. Therein lies the reason why diesel electrics won the survival battle. Diesel electrics had the advantage that railroads could couple as many together as they needed to pull a given train and only one loco crew was required. The result? The 175,000 steam locomotives built in the US over the past 120 years are now gone, entirely replaced by 27,000 diesel electrics and a few hundred electric locomotives. And the rest of the world followed suit, largely because they had to. The big three American steam locomotive manufacturers Baldwin, The American Locomotive Company (Alco) and Lima - all had trouble seeing the diesel electric ECONOMY TRANSFORMERS 1-9 ARLEC SUPER TOOL 10 + 2155 240 V6-15V 1A Cat. M12155 $9.95 $8.95 2156 240V 6- 1SV 2A Ca t. M1 2 156 $14.95 $13.95 2840 240V 9V CT Cat. M1 2840 - $5.95 $4.95 2851 240V 12-SV CT 1SOmA Cat. M1285 1 $5.95 $5.50 2860 240V 15V CT 250mA Cat. M1 2860 $5.95 $4.95 6672 240 V 15-30V 1A tapped Cat. M1 6672 $14 .95 $13.95 DB25 CONNECTOR SPECIALS! 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' Oenotl:S registered !racfmarks ol their respeclrve owners RELICS OF A BYGONE ERA - SANTA FE's 2900 class steam locomotives used 2-metre high driving wheels to achieve express speeds and pulled a huge tender that carried 32 tonnes of fuel and 120 tonnes of water. Despite their low running costs, nothing could stop the trend to diesel-electric locos and the Santa Fe steam era ended in 1959. trend coming. And they all found that tradition means little in competitive business. Three newcomers to the loco building business had appeared on the American scene. Electromotive Division (EMD) The General Motors Corporation in 1941 established their Electromotive Division which soon became known to the world as EMD, maker today of most diesel electric locomotives (89 % of American production one year). Even when manufacturers outside the USA produce locos, often the diesel engine used is an EMD product. In 1942 EMD unveiled to the world their new philosophy railroads would find it cheaper to purchase EMD diesel electric locomotives ready made "off the showroom floor" and couple as many as needed together for each haulage task. Revolutionary thinking indeed! And it took some years for the railroads to see this new wisdom. Eventually they did. Any number of smaller diesel electric locomotives could be coupled together and controlled in unison by one driver with one motor controller situated at the head end. If a railroad needed 6000hp (4.5MW), simply sell them six 82 SILICON CHIP lO00hp (746kW) locomotives or four 1500hp (1.12MW) units and let the user couple them all together. For loads up to about 25,000 tonnes, the very large couplings and drawbar systems already in use in the USA would allow an incredible number of diesel electric locomotives to be coupled together at the head end. In America six locos coupled .together is a common sight with up to twelve being occasionally used in mountain regions where long cork-screw tunnels inhibit the use of radio controlled locos in midtrain. This "multiple coupled locomotive" philosophy was expounded by the EMD salesmen, pushing the belief that no longer was it necessary to custom-design locomotives for a particular rail-road. General Electric, experienced in electric locomotive production for many years, had less trouble in turning to diesel electric manufacture than did factories like Baldwin. The latter had enormous investments in plant tailored to steamer production, a dedication which severely dented their fortunes. A worse mistake was its failure to see that railroads no longer needed single huge locomotives. Traditionally the big three had custom built large steam locos to the requirements of each railroad. They even designed locomotives specifically for one mountain section of line. Don't laugh, Australian railways did likewise. For example, the NSW 57-class steam locomotive was designed specifically to conquer the Blue Mountain section from Emu Plains to Lithgow. So specific was that design that the 57-class could not run on the northern line of NSW. The wide firebox and ashpan of the 5 7-class would not pass through platforms of stations to the north of Hornsby. So the idea of "general purpose" locomotives took some getting used to. While the big three did eventually enter diesel electric locomotive production, they had to contend with EMD as well as the other two innovative newcomers. For a while the innovations challenged EMD's "stock line" philosophy. But that story we leave till next month. l!tl Subscribers Are you about to change your address? Please advise us by the middle of the month to ensure that your next issue arrives at your new address.