Research Rides the Rails..
(Above) STREAMLINED SINGLE-CAR TRAINSARE
SHORTRUNS
POPULAR O N
Courtesy, American Car and Foundry Company
(Below) STREAMLINED SHEATHINQ AND ROLLER BEARINGS
cHARACTERIZE M~~~~~ LIGHT-wEIQHT pAssENGER T~~~~~
S
OMETHING has happened to the railroads. Evidence is to be found on every hand. Just what it is and why it is are less evident on the surface. Yet surface manifestations of a deep-seated change are obvious and important. Lately a great gathering of railway men and those who supply them equipment and materials attracted an important display of what is new in railroad equipment, and there was sought a quick view of the railroad revolution. To find the cause of the present rail renaissance, we must search in the now distant past for t h e guiding thought in railroad management and operation. The era of “the public be damned’’ ended long ago with the beginning and growth of what may be called the age of “safety first.” For decades those two words so dominated railroad thinking that every other consideration was forced almost out of mind. The wrecks of a generation ago were major calamities and involved staggering losses of human lives and money values. In even the least of them, wooden cars collapsed, splintered, telescoped with each other to magnify minor mishaps into catastrophes. Happily the solution was found in strong steel equipment, in innumerable safety devices which took control of the train at
.
The consequence has been that the very bulk and meiglit of rail equipment has laid this vital transportation system at the mercy of others more rapid in their development. With mass and size has come safety but also a certain inertia both physical and mental. This tendency towards immobility of outlook has not hampered automotive development nor has it interfered with the swift growth of air transport. Both of these newcomers took toll from railroad revenues to such an extent that something had to be done to save these vital carriers. No change of such a fundamental character as was needed here could be put into effect over the whole country quickly. From its very nature it had to be accomplished by degrees and with the most careful consideration of each step. Already most of the technology required has been developed in other fields to a point where the railroad problem becomes primarily one of adaptation. Yet even this adaptation had to be accomplished in a system of vast proportions where units must always be completely interchangeable in such a way as not to interfere with its continuing and continuous operation. Kew cars must always be interchangeable with old and both must be able to operate in the same train. Under such circumstances, adaptation is a major problem.
Nature of the Problem Obviously the first step was to state the problem correctly. This was complicated by the many points from which it could be viewed, but in the main the railroads must carry passengers and goods safely, quickly, and cheaply over long distanes if they are to succeed. Highway transport has proved convenient, cheap, and rapid over shorter distances. Airplanes pro-
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SEPTEMBER, 1937
vide a swiftness over long distances still unattainable otherwise, but necessarily their flight requires relatively large power to hold cargoes aloft, too large to allow them to compete in the usual freight haul. This, then, requires the railroads to develop speed, convenience, and economy as their means of regaining and retaining their position as basic carriers. Perhaps a better division of the problem would include speed with convenience and make them correlative with economy, which represents the public's requirements. Stated in such terms the problem has numerous important ramifications and requires to be broken down further into more definite parts to fit the railroads' point of view. Whatever else may be done, safety cannot be impaired in the slightest degree.
Locomotive Design Higher speed requires that greater power be applied to the same load or that the same power be used to draw a smaller load. Steam locomotive boilers (rail men are reasonably sure that steam locomotives must continue to be their most useful power units) are closely approaching the limits of increased size as a means of gaining more power. Already the handling of a giant locomotive, even with modern mechanical aids, is becoming difficult almost to the point of jeopardizing the safety factor. Tunnel and right-of-way clearances limit cross-sectional increases, and length is held down by the limits imposed by curves. TABLEI. IMPROVEMEXTS IN LOCOMOTIVES (9) Year
Type
Max. Indicated
H. P. per Driving Axle
H. P . 1904 1914 E915 1922 1925 1933
2- 8-0 2- 8-2 2- 8-2 2- 8-2 2- 8 - 4 2-10-4
Freight Locomotives 1036" 260 625 2500 709 2s37a 2965 741 972 3890 1171 5855 Passenger Locomotives 522" 261 612 1224" 979 1958= 1177 2355" 1244 248W 1061 3183" 1358 4075 1600 3200b
4- 4-0 1895 4-4-2 1904 4-4-2 1910 4-4-2 1912 1914 4-4-2 4-6-2 1915 4-64 1927 1937 4-4-2 Test plant data. b Calculated; others from road tests.
.4v. Weight per Driving Bxle Lb. 43,300 60,000 59,000 62.000 62 000
Indicated H. P. per Ton on Drivers
12
20 8
74:500
24.0 23.9 31.3 31.4
28,000 55,000 64,000 70,000 66,500 67,600 62,000 70,000
18 6 22 2 30 5 33 6 37 4 31 4 43 8 45 7
Q
Consequently the problem of power becomes one of efficiency of steam production and use. Here, again, the obvious answer of higher boiler pressures is apparently impossible because of the limitations of locomotive fire tube boilers. A pressure greater than the present maximum of 300 to 325 pounds per square inch would so fill the boiler space with the stay bolts required for strength that necessary rapid circulation of water would be unduly impeded. Condensing engines have been considered but discarded as impractical with the limited water supply of a locomotive and space limitations on air condensers. An important second consideration in this question is the present necessity of using the exhaust steam to produce draft for the fire. Even multiple expansion engines must be left out of the improved efficiency possibilities because of the immense size (interfering with clearances) of their low-pressure cylinders. All of these limitations, some of which may well be removed by the development of entirely new types of equipment, have left the locomotive designer with a narrow field for his operations. Within it, increased efficiency in the use of steam has in thirty years brought steam consumption down from about 28
1003
pounds per indicator horsepower hour to barely half that in road service, and further savings are in immediate prospect. Redesign of the running gear to increase its efficiency, lightening connecting rods by making them of alloy steels to reduce inertia loads, improvements in wheel design to balance rotating weights more accurately a t greater speeds, and otherwise improving the mechanical efficiency of this fundamental power unit, all have been important. Accurate dynamic balancing of rotating and reciprocating weights is essential to higher speeds because any lack of precision produces serious damaging shocks to the track. Although lacking much of the fixity of the past, the railroad view of its power plant is definitely centered on the steam locomotive. Electric locomotives must necessarily operate in regions where electric power is cheap, where frequency of the train service supplies a more or less balanced load for the electric power plant, or where other considerations become paramount, as in congested city areas. Gasoline engines have been used in single-car units. Diesel power has'been proved successful in operating regular railroad trains across the continent. High and increasing efficiency of Diesel engines assures them an important place in the railroad sun of the next generation, but the innate conservatism of railroad managements will probably confine Diesel service to special situations for some time. Of a total of 234 Diesel locomotives in service at the beginning of this year, only 18 were in road service, the remainder being used in transfer and switching. Probably no source of power will ever be as cheap as coal for most railroads, particularly in view of their original development to includf coal areas in the respective territories of each. In the power field, then, we may reasonably expect impor tant developments in coal-fired steam locomotives, even is. cluding radical departures from current practice. Diesel and electric locomotives probably will occupy special fields, particularly that of high-speed passenger service where their comparative freedom from heavy reciprocating parts minimizes damaging shocks to both track and engine. Streamlining has attracted special attention lately with the advent of ultrafast passenger trains. From the public's point of view, streamlining and air conditioning are the important points about these trains, for the first is connected with speed and the second with passenger comfort. Railroad men stress light weight in the new cars and look on them as experiments primarily in the direction of reduced nonpay load. Streamlining from the railroad point of view is still a long way from standard practice, for the enormous weight of present cars (both passenger and freight) is too great a power consumer to be offset by any reasonably expected saving through streamlining. The opinion is held, that the weight added to a locomotive in the process of shaping it to a streamlined form may more than offset any gain to be anticipated from its reduced air resistance. Similarly, the dead weight of cars now in service would be in reased beyond the profit point if streamlined shields were added to them. Necessarily, the decision rests on speed alone, for air resistance that is of no moment a t 30 miles per hour is substantial a t double and higher velocities.
Car Structure On the other hand, the conception of a train as a unit rather than as an aggregation of engine and cars, and the redesign of this unit to serve a particular purpose are very much to the fore in railroad thinking. The railroad car, from an engineering point of view, has most nearly resembled a covered bridge between its two trucks, the essential difference being that the car is carried on what is virtually a two-point suspension. Although the car body in the past has contributed to strength, the new trend is towards a better and better utilization of the whole fabric of the car for purposes of structural strength. The side whlls are being developed into trusses, and
b
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SEPTEMBER, 1937
INDUSTRIAL AND ENGI NEERING CHEMISTRY
even the roof takes part in carrying the load. By utilizing this method of design and discarding unnecessary material which does not contribute to the strength of the entire unit, it has been possible to effect substantial savings of weight throughout the car structure. Carrying this trend to its ultiinate conclusion, the car becomes a tube of trusses, and the sheathing applied to this tube can be made as light as desired. Although this phase of car and train design has received special prominence recently, it has been developing in a less pronounced degree for many years, and the present trend is towards a general adoption and practice of ideas never before so freely used. Coupled with the redesign of the car unit has been the substitution of stronger alloy steels to reduce weight still further. Aluminum alloys are similarly used. The trend in design includes many other changes in technic looking towards the same .end-lightness of load-carrying equipment. Power equipment does not lend itself to the weight-reducing process since tractive effort is necessarily a function of the friction between driving wheels and rails and that, in turn, is greater, the greater the weight on the wheels. Cars, on the contrary, are merely vehicles for their contents and constitute unavoidable dead weight; any reduction of this dead weight, consistent with safety, is advantageous. The old idea that weight is essential to keep cars on tracks has given way to the more reasonable view that dead weight is less important in this respect than proper location of the center of gravity with respect t o rails and a more complete control of the vibration of cars with their loads. Vibration may become a serious factor through the fact that small, regularly transmitted impulses may set up synchronous movements in car springs. In this way a whole train may be set into such violent lateral or vertical motion as to jump from the track. This tendency is being overcome by the use of various devices for damping spring travel so that harmful motion can be snubbed before it becomes serious. Similarly a reduction in nonsprung weight and more accurate finishing of freight car wheels to secure exact concentricity are part of the improvement in railroad cars. . The adoption of alloy steels of high tensile strength to replace mild carbon steels is contributing importantly to the reduction of car weight. Some of the steels used are already standard elsewhere. Others have been specially developed for railroads. Simultaneously, improvements in car wheels, the result of a long program of cooperative research, and in the design of car trucks have lightened these essential parts of the structure without sacrificing strength or safety. ’ Roller and ball bearings, applied so far to locomotive and passenger car wheel bearings, are materially reducing the force required to start and propel a train. Essential in the whole picture is the improved practice achieved through welding. Formerly all joints in railroad equipment were riveted. Strong as this construction is, it adds weight to the finished job, weight which modern welding efficiency makes unnecessary. Welding of alloy steels presented a special problem in railroad equipment since it is essential that minimal changes be produced in the character of the steel to maintain its strength and corrosion resistance. The welding of thin sheets required for sheathing cars was a particularly difficult case. The solution of this problem has, however, been successfully accomplished by electric welding methods based on the instantaneous development of welding temperatures in very small areas. Members of larger cross section caused less trouble. Welding has entered the car building picture to stay, and riveted construction is likely to be used less and less in the future. Sonferrous alloys and metals are used to some extent in car construction, but the general attitude of railroad men is t o stick to steel and to gain lightness by using high-tensile ferrous
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,
alloys. Aluminum alloy truck frames and car bodies have been successfully built and used and may yet become more generally useful. The development reported from abroad of alloys of copper and aluminum with lithium, beryllium, and other alloying ingredients for railroad service has not yet convinced American carriers of the utility and value of these materials except in isolated instances for special purposes. Here, again, the innate conservatism of railroad thinking shows itself. Development of aluminum alloys and their use for special purposes may well provide the entering wedge for more general application of nonferrous metals.
Improvement in Freight and Passenger Service In the foregoing we have dealt in general considerations applicable to all types of rail service. These ideas and developments are of the utmost importance since they lie a t the base of our most useful transportation system. By applying these principles, the dead weight of a freight car for ordinary or for refrigerated service has already been reduced by 5 tons. Not only can this reduction be effected now in cars having an average weight of 23 tons without affecting safety and cargo capacity, but the cost of the new light car may be no greater than that of its heavier predecessor of equal load capacity. Translated to other terms, this means that a locomotive accustomed to drawing a 40-car train can with the same expenditure of fuel haul as much as 200 tons more pay freight over the same route. Actually this is equivalent to an increase of 10 to 12 per cent in pay load or an economy of the same proportion in the cost of rail transportation. In passenger service the improvement already achieved is quite as striking. The public appeal of streamlining has somewhat overshadowed the real change which has been made in weight reduction of passenger, as well as of freight, equipment. Part of the weight saving has been utilized to provide new conveniences and comforts for travelers; but in spite of this offset and allowing for differences in type, a reduction of 40 per cent or more has been reached in the new light-weight cars, as compared with the old standards. This has been accomplished in the new alloy streamlined trains. Changes in standard designs, although less radical, have also affected substantial savings in dead weight by replacing mild steel with high-tensile alloy steels, by welding instead of riveting, and by modifying designs to utilize these improvements economically. T9BLE 11. NUMBER -OF PASSENGER CARS WITH VARIOUS TYPES OF AIR CONDITIONING (1) --Compression Year Installed 1933 1934 1935 1936
Steam 41 197 549 322 ~
Total
1109
Ice llctlvated 297 749 993 1131 ~
3170
System-Independent drive
Motor drive
Direct drive
218 438 1725 333
-
92 494 82 704
__
1 63
648 1878 3350 2553
2714
1372
04
8429
-
Tota
~
Most significant has been the growth of air conditioning as standard in passenger equipment (Table 11). Insulation of steel car bodies more effectively than heretofore and design of ducting systems supplying treated air throughout the car have been the principal problems of the car builders. Both fibrous (organic and inorganic) and metal foil insulations are used. Air washing, filtering, and cooling systems in great variety have been made available for car use. One type depends upon power drawn direct from the car axle, another stores power from this source in storage batteries for use when needed. These methods provide power for cooling and circulating air by indirectly utilizing the locomotive’s output and are widely used. However, despite convenience in normal car operation, indirect power supply has disadvantages. Others have sought.
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INDUSTRIAL AND ENGINEERING CHEMISTRY
to overcome its defects and inefficiencies by drawing power more directly from the locomotive as steam for operating a vacuum refrigeration system. Still another system depends upon an internal combustion motor driven by propane stored underneath the car for its power, each car having a completely independent plant of its own. These and other refrigeration systems are replacing units in which ice is the cooling agent. Rapid strides in this field assure increasing passenger comfort in the future. Almost as significant from the passengers’ standpoint as any of these developments is the trend towards design of trains as complete units. Passenger requirements and desires are being met in increasing degree by the inclusion in unit trains of all reasonable services. By integrating these into welldesigned equipment, designers are providing greater economy of operation, vital to the railroads, and greater travel comfort on which depends increased patronage.
VOL. 29, NO. 9
Obvious throughout the railroad world today is the investigative spirit of research, both into the physical requirements of efficient transportation and into the too-long-neglected aspects of consumer service necessary to increased use of railroad facilities. Cooperative research by the Association of American Railroads through numerous active committees, by organizations supplying equipment and materials, and by independent and quasi-independent agencies is actively developing our railroad systems to meet modern needs well. The value of this movement to all concerned is obvious.
Literature Cited (1) Am. Assoc. Railroads, Mech. Div.’, Report of Comm. on Air Conditioning and Equipment Lighting at Atlantic City, N. J., June 18, 1937. (2) Winterrowd, N’. H., paper presented before Mech. Div., Assoc Am. Railroads, Atlantic City, N. J., June 17, 1937. R B I C E I V July ~ D 13, 1937.
Lost Monopolies of Names and Things E. W. LEAVENWORTH Watson, Bristol, Johnson & Leavenwortb, 6 East 45th Street, N e w York, N. Y.
T
HE fate that has overtaken such well-known names as aspirin and cellophane has aroused interest and comment, and some of the comment is decidedly pessimistic. It is said, for example, that the manufacturer who invents a name to use as his trade-mark, and who succeeds in making it so well known that it comes into common usage, is likely, because of his success, to lose the monopoly of the name just when it has become most valuable. Questions are asked as to ways and means of avoiding the risk of losing the monopoly. Has anything helpful been learned, and if so what is it? How would a prudent person proceed from the start in order to adopt a trade-mark and make it valuable without risk of losing it?
Cellophane The histories of the lost monopolies are strikingly alike, but none teaches so many helpful lessons as that of cellophane. The word cellophane was coined in France in 1909 by Brandenburger, an inventor whose inventions are credited with the production and use of cellophane in commerce. He coined the word as suggesting a transparent product made of cellulose, but was not content to use it as aproduct name. He wanted to monopolize it, so he registered “ L a Cellophane” as a trade-mark. He did not coin any other name for the product although commercially it was a new product which had never been known to the public or sold, and which had no name even among chemists other than a chemical description. He permitted it to go nameless commercially except in so far as the name which he claimed as a trademark might be used as the name of the product. So the labels on the first shipments of the product to this aountry in 1911 read “Cellophane” or “La Cellophane” with nothing more except specifications of color, size, etc. The meaning conveyed by such labels was that the packages con-
tained cellophane. It was not that the packages contained the Cellophane brand of some otherwise known thing. The labels introduced the word cellophane as the name of a new product. The advertising followed the lead of the labels by featuring cellophane, not as a brand, but as the product itself, a “superior wrapping material.’’ Some of the advertisements stated that “Cellophane” was a registered trade-mark (the word having been registered here by an importer) but used the word as the name of the product. Other publicity of the period, such as an occasional article or news item in a newspaper, magazine, or scientific journal, used the word cellophane as the name of the product and helped to make the word a part of the common vocabulary. When an American manufacturer took over the United States business in 1923, the word cellophane had been used and known as a product name in this country for twelve years. It would have been It then to build up for the that ceQophane is not just word a new meaning to the a product but a particular brand of a product. It would have been impossible to do so without teaching and persuading the public to adopt another name for the product sufficiently specific to be capable of identifying the product as distinct from all other materials. Without such a name purchasers of the product would have no name except cellophane which they could use with assurance that they would get what they wanted, other manufacturers would be unable to compete unless they could sell their product as cellophane, and the alleged trade-mark monopoly would be a perpetual product monopoly in disguise. This brings us to the main lesson taught by cellophane and the other lost monopolies : A product or thing may lawfully be monopolized only by patent and during the patent period. When it appears that the monopoly of a name will result in
