The Iron Age 1925-12-10: Vol 116 Iss 24

eT aa eee ESTABLISHED 1855 I OU are driving down a country road one sunny morning in 1950. You stop beside a prosperous farmhouse and clamber out in seach of water for the radiator’s innards. Behind the house is a huge steel shed similar to a hangar—but there are no fragile planes in that shed; only a dozen huge-wheeled,-snub-nosed machines which would find it hard to leave the ground save under the persuasive influence of a hoist. You approach one of the overalled mechanics who is busy with a spanner tightening various parts of a tractor. “Where’s the farmer?” “I’m the farmer,” replies he of the wrench. “What can I do for you?” Back in 1925 you might have been surprised to find a son of the soil looking like a machinist, but in 1950 you are not astonished. The machinist has come to the farm to stay. Farming is a mechanical industry in 1950. II F you think that such a view of the future is exag- gerated, recall the changes which have taken place in the last two generations. Sixty years ago the power for farms was furnished by animals. Horses and mules and oxen still help the farmer. But their proportion of the total power used on farms is less each year. Today more than half the primary power on our farms is me- chanical. The beast of burden requires a machinist more often than a veterinary. Farms use more power than all our mines and fac tories. And in two short generations, more than half this enormous transformation has been effected. Nor does it stop at the power phase of agriculture. From hay stackers to potato diggers, the whole field of agri- culture is being revolutionized—mechanized. In 1850 the production of agricultural implements was less than $7,000,000. Last year the output of farm machinery, including tractors, passed the $300,000,000 mark. THE IRON AGE New York, December 10, 1925 1579 VOL. 116, No. 24 Mechanizing the Farm: A Prophecy How a Revolution in Agricultural Methods Is Taking Place and What It Holds in Store for the Metal Trades BY PRENTICE WINCHELL But this is only a beginning. Rapid as has been the growth in use of mechanical aids for food produc- tion, such applications in the future will be even more rapid. There are many reasons for this. IIT TRONGEST of many reasons is the growth of population. Econo- mists say that popula- tion tends to double about every 25 to 30 years. Statistics show that this is close to the facts in the United States. If the present trend is maintained— and there is no reason Population in the United States : . joubles about every thirty years. to suppose it will not What will it be in 1940? 19702 be—the United States will have to supply food for some 175,000,000 people in 1950—perhaps many millions more. Nor is there any reason to suppose that new terri- tory will be added to our possessions in any such ratio as the increase in population. Our population per square mile has been doubling about every 40 years. This simply means that more food will have to come from every acre. Now it is a well-understood fact that the more food which must be grown on any given area of land, the more labor in proportion is required to produce it. The best and richest land is used first, naturally. As the need for more and more food brings into use the less productive land, more work is needed to grow the bushel of potatoes or the peck of peas. Under these circumstances, rapidly growing popu- lation, need for increased food production and an ac- celerating cost of production, it will be seen that not only would more labor be needed on the farms, but food TS noe neo ees Prats eeciniries ie ver ed Sed rik oe ae een wa er he ony rer errmneneiatl ogg pate ag selbibertpnege=+ theleemipemnes Duly myarms “RANE noe ttm TONE wr 2 <= re.) ssigteetMa Rs doce? a a\¢ 9 - i eS td eT Te year? nea SAE AT NS - «pg - J 1580 would cost more and living costs in general would ad- vance. All of these things would undoubtedly have their effect today were it not for the improvements in agri- cultural methods, and particularly, the increased use of machinery. And ing, the need for improved machinery on the farm will as these factors become more press- become more evident and many farmers, who now hesi- tate about purchasing an expensive piece of equipment on grounds of cost, will find that the territory economists call “marginal utility” has been crossed and which that the new equipment is a necessity. [V HAT machinery has done for the farmer is best shown by the productivity of the individual farm hand. Sixty-five years ago 100 average farm workers produ ed enough to feed 651 people. In 1910 these same 100 workers were enabled, by the use of machin- e1 (and improved methods made possible by ma nine! ( produce enough food for 727 people. And 20 the same 100 workers fed 966 hungry mouths Nearly 2,000,000 less workers were required o1 farms in 1920 than ten years earlier. Thus machinery is making possible a reduction the working forces on our farms, despite the increased demands upon them. And it is very possible that the unwillingness of young men to do heavy drudgery or farms has had something to do with high cost of farn labor and consequently with the introduction of ma Certain it is that, with the growth of popu lation, the enormous increase in demand for food and the reluctance of labor to do the old type oI larm work, machinery offers the only solution. Moreover, as more food is required, more land must used to produce it. With every increase in area cultivated, the efficiency of machine farming becomes vident. Less than one-fifth of the land area of this country now cultivation, according to that half our land will be used for agri under Government estimates. Some say the day will come when nearly culture—but if the increase is very much less than that, an expansion f vllow. in the use of farm machinery will surely NOTHER facto: tarded the which has re- sale of farm equipment has been the dif- ficulty of adapting present implements to machine use. Many a clings to obsolete equipment manufacturer because he does not know how to get any value out of adapta it through sale or tion and because he thinks he cannot afford to throw ; liens Meee away that much money. tractors The farmer has made the ne same mistake concerning his implements. A recent bulletin of the Department of Agriculture pointed out that most farm implements intended for field work were originally designed for the use of animal power. When tractors came into use for field work, they were easily adapted to the majority of the operations required for non-row crops, but for row crops there have been difficulties which meant the de- signing of new equipment. Each year sees newly de- signed implements for use with tractors; each year THE IRON AGE December 10, 1925 sees many of the old implements worn out or discarded. The use of machinery is increased thereby. Another factor is the changing in training of the farmer. Our agricultural schools and colleges are turning out thousands of tomorrow’s farmers who are believers in mechanizing the farm. Many of them will design and invent new applications of power to the cul- tivation of the soil, planting of crops, harvesting, stor- ing and transporting of grain and all the duties which formerly took man or horse power. Still another reason for expecting increased sales of farm equipment is the competition which our farmers have to face from cheap food products grown More efficient production will help to offset this disadvantage in the world markets. abroad. VI HAT is true of the United States in particular is \ \ true of the rest of the world in general. So far as plentiful food supplies for a steadily increasing pop- ulation are concerned, there is but one solution, a grow- ing use of farm machinery, milking machines, seeders, huskers, the thousand and one items of farm machinery plus the appliances which are necessary to keep such equipment in good running order. Therefore manufac- turers of such machines and appliances may and do expect a continual gain in demand for their products. Is there any reasonable way of determining how much ‘f an increase may be anticipated during a _ given period? the number of fed and the amount of food required. There is a direct relation between mouths to be Quality or variety of food products might conceivably change considerably, but quantity could not be reduced per person without immediate and_ seriotfs_ results. There may be many who eat overmuch—but there are also some who are not properly fed. The quantity of food consumed in the United States (regardless of ex- ports or imports) might well be expected to double every 50 years. What are the facts in regard to value of actual production? From 1890 to 1920 the total wealth pro- duced by farms (crops, livestock, dairy products, etc., but not including gain in farm property) showed a distinct tendency to double every decade. If constant, and exports and imports were eliminated, the tendency would presumably be to double once every 50 years. value of prices were But price increases, large exports and growth of consumption combined to give a total farm production in 1890 of about $2,500,000,000; 1900, $5,000,000,000; 1910, $9,000,000,000, and 1920, $18,- 000,000,000. (All figures approximate.) How much machinery is employed to produce this enormous wealth? The Department of Commerce lists the total value of all farm implements and machinery on farms in 1890 as $494,000,000. Ten years later, when food production had doubled, the value of imple- ments and machinery had advanced to $749,000,000— about a 50 per cent increase. After another decade, the value of such equipment was estimated at $1,265,- 000,000—this time more than a 50 per cent increase. And during the last decade in question, the value of implements and machinery on farms jumped to $3,594,- 000,000—not far from three times the value in pre- vious years. Difference in price levels, errors of computation and lack of comparable data may all be brought into the problem to justify any discrepancies which appear, but the fact remains that in recent years the gain in value of machinery employed on farms has been more rapid than formerly. This bears out the contention previously made, that as population increases and food December 10, 1925 becomes increasingly difficult to produce, the applica- tion of machinery to farming will be steadily accel- erated. VII ERE is another element which enters into the fu- ture of farm machinery and those who produce the raw materials for it as well as those who actually manufacture the imple- ments. This is the ele- ment which, overlooked for many years by the automobile business, is now the mainstay of that industry. We refer to re- Total production of farm im- Placements. It is well plements, dotted area. Output known that a very large of tractors, lined area. The proportion of the total trend is clearly upward despite : . : business in automobiles the drop after the unusual busi- : is now traced to replace- ness of 1920. ment orders. Farm implements and machines also have to be replaced, of course. Manufacturers have been getting replacement orders for many years. But with every increase in total value of farm implements in use, the total annual replacement business must show a corre sponding gain. Fifteen years ago, when the entire Compressed Gas Manufacturers to Meet in January The Compressed Gas Manufacturers’ Association will hold its thirteenth annual meeting on Jan. 25, 1926, at the Hotel Astor, New York. The association represents manufacturers of all industrial gases, such as acetylene, ammonia, carbonic gas, chlorine, hydro- gen, nitrous oxide, nitrogen, oxygen, sulphur dioxide and various hydrocarbon gases. These gases are used for isolated lighting and heating plants, in the fabri- cation of metal by means of the welding and cutting . torch, for mechanical refrigeration, for carbonation of beverages, for bleaching in the textile and paper indus- | tries, in the purification of water and sewage by 7 chlorination, as anaesthetics, in fire extinction, and for various other purposes. The value of compressed gases consumed in the United States yearly is now estimated as at least ; $60,000,000. They are transported under high pressure in steel cylinders or tank cars. About 4,000,000 gas cylinders are in service representing an investment of some $40,000,000. The headquarters of the association are at 120 é West Forty-second Street, New York, and John H. Luening is secretary. + A dipper dredge is now under eonstruction at the works of the Bucyrus Co., South Milwaukee, Wis. It will be driven through electric motors by Diese! en- gines of 1200 hp. capacity, the fact that the Diesel engines have been applied being of interest in addi- tion to the size of the dredge. THE IRON AGE 1581 valuation of such machinery in use on farms was $1,- 265,000,000, replacement business was, perhaps, not such an important item. Today, when new machines are being placed on the market every month, when graduates of agricultural colleges apply scientific methods to the old farm, and when the total value of farm equipment must be well above the $4,000,000,000 mark, the replacement business is of much more im- portance. Twenty-five years from now, if population is double that of 1920, when food production will have increased proportionately (possibly exports may drop and im- ports increase) when the total value of farm imple- ments climbs toward the $10,000,000,000 mark, then the replacement business will presumably dominate the implement industry as it does the automotive industry today in the domestic market. Those who were astonished at the continual acceler- ation of automobile production will probably be aston- ished again by the great strides which the agricultural machinery business will make in the next decade or two. But those who look at the figures concerning population, food, farm labor and the use of imple- ments will not be surprised. As the age of hand production of industrial articles has largely given way to the machine production of commodities, so will the planting and growing and har- vesting of food become a machine, rather than a hand, industry. The old order changeth before our eyes. | \ a Steel Treaters’ Winter Sectional Meeting at Buffalo Active preparations are being made by the Buffalo Chapter of the American Society for Steel Treating for the winter sectional meeting which will be held at the Hotel Statler on Thursday and Friday, Jan. 21 and 22. The chairman of the chapter, G. J. Armstrong, has appointed five committees, one on publicity, another on registration, a third on finance, a fourth for the dinner and a fifth on entertainment and arrangements, and they are all actively at work. Some of the metal- lurgists who will deliver papers are H. J. French, of the Bureau of Standards; Dr. Egeberg, Halcomb Steel Co., Syracuse, N. Y., and E. C. Bain, Union Carbide and Carbon Research Laboratories, Long Island City, N. Y. On the day preceding the opening of the sec tional meeting, the first session of the newly elected directors of the national society will be held. “Concentration in Boilers,” a paper read by Grant D. Bradshaw, Andrews-Bradshaw Co., Pittsburgh, be- fore the Engineering Society of Western Pennsylvania, has been reprinted and is being distributed by the com- pany. It deals with treatment of feed water for boiler use, to prevent scaling and other difficulties in opera- tion. The American Oil Burner Association will hold its next annual convention and exposition at the Book Cadi lac Hotel, Detroit, April 6 to 8, 1926. Leod D. Becker, 350 Madison Avenue, New York, is executive secretary. Machine-Shop Facilities Improve Progress Summarized in Report Submitted at Meeting of Mechanical Engineers—Optical Measurements, Design Fallacies and Gear Problems Discussed COMPREHENSIVE report of the progress shop facilities during the past few years was one of several contributions of the machine-sho} practice division of the American Society of Mechanical Engineers to the forty-sixth annual meeting of the society, held in the Engineering Societies Building, New York, Nov. 30-De 1. This report, together with similar £ progress reports of the other professional divisions of the society, was presented at the general session held Dec. 2, and was read by W. F. Dixon, works manage} of the Singer Mfg. Co., Elizabethport, N. J., and chair- man of the shop practice division. The use and advantages of optical measuring struments, some fallacies in machine design, and a dis cussion of gear problems were among the subject taken up at other sessions arranged by the machin¢ sho} practice division. Progress a Matter of Orderly Development Che improvement in shop facilities was said been to a considerable extent a matter of the order levelopme f known principles, rather than the d covery of new ones. There are nevertheless ex which are noted in the report. According to the report, the general tendency ha been, quite properly, toward relieving the operator more and mere of the burden of tedious hand labor. As new machine tools are substituted for older ones, the operator usually finds that more power and more of his employer’s capital have been placed under his control, and that this condition has been accompanied by the capacity for doing more and better work s end, machine-shop machinery is being de- signed stronger and heavier, and more power is being ipplied t t Direct electric-motor drive for machines s coming into greater use, partly as a result of ap plying more power to the machines and partly because ' its facilit f control. To a great extent, however, individual-motor drive is popular in spite of more costly installation because it makes possible a cleaner and light shop, eliminates overhead works, and permits the icing of machinery to greater advantage. Motor lriv ng further developed into unit drive. Several motors are often applied to one machine as this elin plicated gear trains and in some cases helps toward re economical construction. Sometimes the base of the machine incloses the motor. rication is receiving more and more considera Pressure and splash feed to all bearings and geal th filters on the return, are becoming commo! The nec ty for improved lubrication increases n ecomes more complicated, more powe1 applied nd greater accuracy and longer life are demand Son of these latter reasons have turned mar nachine builders to the use of ball and rolle bea gs, which are installed quite as often to assur uninterrupted service and freedom from lubricatior power. Machine control is another factor which is claiming re ent Hand-cranking of tables, car- ges, and slides is being replaced by fast feed move- ment ontrolled by handy levers or push buttons, whic! e both the time and energy of the operator. M: f b ynserving device . such as chucks Am} perated mechanically, hydraulically, ele« trical y compressed air, are coming into use and are rapidly superseding those manually operated. Entire rooms occupied by machines working on cast iron are served by dust-collecting systems which clea ind change the air, keep the floors clean, and minimiz« the necessity for brushing fixtures. Increasing atten- tion is being given to the elimination of accidents by guarding dangerous mechanisms, and specially trained men are being employed to look for and correct hazar- dous machines and practices. All-geared heads and single-pulley drives, for example, increase the oper- ator’s safety. Hopper and magazine feeds are becoming common on high-production machines for light and medium- weight parts Basic Machine Tools Improved In lathes, mention might be made of one huge irning machine recently built which swings 300,000 b. between centers and has eight electric motors and 6-in. grinding machine built on a carriage for use anywhere along its 45 ft. of working length. The designs of other new lathes include automatic features, multiple-feed slides, and single-pulley drives, and on at least one of these machines the work is fed automatic- ally from a magazine. Planing machines are being provided with ywer fast traverse, faster cutting and return speeds, and better lubrication. Milling machines now have stiffer over-arms, fast power table feeds and motors inside the column. The special and manufacturing types have been developed to do a wide variety of work; in some casgs they com- pete with the planer in the job shop, while in others they operate continuously on quantity production. The development of these manufacturing millers has been of prime importance to some industries. For drilling, we have more rigid machines, higher- peed machines, and more sensitive machines. Mul- iple-spindle drills (both standard and special) are being yuilt for larger production. If quantities warrant, it is usually possible to secure a machine, made up of semi-standard units, to drill all the holes in a part from almost any direction. Rapid Progress in Grinding Process Grinding as a shop process has been developed re- ly during the past few years. One of the most itstanding of these developments is the centerless grinder, the unusual production and precision possibili- ties of which have opened up wide fields for its use. Improvements on internal grinders extend from an at- tachment on a universal grinding machine to an almost automatic machine which is self-gaging, self-dressing, and self-feeding. Cylindrical grinders are being made with better bearings, better lubrication, and greater ease of control. Some auto-loading machines have been built for special production. Wide-wheel straight- in grinding has come into favor on some varieties of work, Extremely powerful and accurate surface grinders are now being built. One of these has a 100-hp. drive, while another has an automatic sizing device and is arranged to finish the work in one pass iarKa inder the wheel. The grinding of threads on taps, gages, hobs, etc., has been a development of recent ears, and some progress has been made in the grind- ng of gears. Disk grinding, which has been developed to a high state of perfection, is an important operation n many industries. Mechanical lapping has filled a need for greater precision and better finish, and machines have been developed to lap both flat and cylindrical parts with great accuracy and high finish. It is possible by this method to economically produce work which is accurate to fractions of a ten-thousandth part of an inch. Besides the general classes of machines mentioned. 1582 December 10, 1925 an endless variety of more or less special machines for centering, tapping, milling, threading, polishing, buf- fing, stamping, etc., is being produced. The increased use of pressed metal, which calls for better and larger presses, has led to the recent development of machines which duplicate automatically blanking and forming dies, iron patterns, molds, and engraved work. To facilitate jig and fixture work there are now available precision boring machines which take the guessing out of this line of work and effect a great saving in cost. The use of automatic machinery has extended to the heat-treating shop, where various mechanical de- vices make this phase of manufacture more accurate and economical, and more pleasant for those engaged in it. Important Developments in Measuring Devices One of the most important developments has been that of precision measuring. Some time ago we passed from the caliper to the micrometer. Now we are pass- ing from the micrometer to the precision gage block, the sensitive comparator, and light interference as bases for close measurements in the shop. These ac- curate instruments and tools have gone far toward making real interchangeable manufacture possible at a low cost. With the increasing demand for closer limits in shop work, it is fortunate that a standard of measurement can be referred to which is many times times more accurate than is actually required. Along with the mechanical progress made _ in machine-shop practice, there has been a corresponding improvement in human relations in the shop. Lighting, ventilation, cleanliness, and safety are planned into modern shop construction. Hospitals are installed to care for those injured and, in addition, to guard the general health of workers. Schools and apprenticeship systems are being highly developed. Possibilities of Extending Use of Optical Measuring Instruments AX interesting outline of the use of optical measuring instruments and the possibilities of extending their application in the making of machine parts was given by Henry F. Kurtz, optical engineer, scientific bureau, Bausch & Lomb Optical Co., Rochester, N. Y. Mr. Kurtz’s paper, under the subject of “Principles and Advantages of Optical Methods for Measuring Machine Parts,” was presented at the machine shop practice session held Dec. 1. In many cases, said Mr. Kurtz: light, because of its peculiar properties, may be used for making precise measurements of quantities that are entirely beyond the possibilities of the engineer’s usual equipment. The increasing demand for accuracy at low cost has led to the design within the last few years of many optical instruments, four types of optical apparatus having been applied to the measuring of machine parts. The field of application of these devices was said, however, to have been barely touched upon. Interference appartus, one of the types discussed, was said to have a wide potential field of usefulness for the engineer. The optician has checked the plane- ness of surfaces and has compared curvatures and sphericities by means of the interference principle for many years, but it is only within the past few years that the engineer has used this method in the making and checking of master gages. With careful work he is now able to compare lengths with certainty to within observed differences of a few millionths of an inch. It was stated that the principle of interference of light can doubtless be extended to many other phases of mechanical work through the construction of suitable appartus. Such apparatus would not be delicate nor complicated, and would require less skill in use than the ordinary micrometer caliper. The results, it was said, would be a hundred fold more accurate and there- fore much more dependable. Application of the optical lever was briefly dis- cussed, and also imaging systems, by which with the help of lens systems, beams of light may be controlled THE IRON AGE 1583 in such a manner as to form images of objects. These lens systems may be designed to give an image many times larger than the object itself, the errors of the object being magnified to a high degree and becoming correspondingly easier to observe and to measure. The lens system may be arranged to present the image for inspection in a plane containing a measuring device, for instance a scale, cross-hair micrometer, or a stand- ard templet or contour plate, or an accurately made scale drawing of the object under investigation. One of the most serviceable arrangements is that of the projection system, which is coming into use because of the ease of observation, no eyepiece being required, because large magnifications are easily attained, and because a photographic plate may be inserted in the image plane and a permanent and accurate record made of the conditions under investigation. Among several applications shown by lantern slides was a microscope arranged for setting the cutting tool in a machine, the tool being set in a few minutes to an accuracy of about 0.001 in. Previous to the adoption of this method the tool could be set only by trial and error, at the expense of % hr. in time. Thread tool- setting microscopes were also shown, these devices per- mitting judging the angle of the tool and its angu- lar position to within a few minutes of arc. A tool maker’s microscope used in locating holes in a drill jig was another device of interest, as well as a Goni- ometer eyepiece for tool makers’ microscopes. The latter permits measuring flank angle and angle of “lean” as well as helix angle of screw and also making angular measurements on other machine parts. Two Optical Projection Types In optical projection apparatus two types were dis- cussed: 1, Comparators, by means of which the pro- jected image of a thread is compared with a standard outline, and 2, direct measuring apparatus, which does not require a standard of comparison. An interesting section of the paper was devoted to optical scale reading. Angle measuring tools used by the tool maker are usually provided with scales and verniers divided on steel. The verniers are hard to read for the average mechanic, the lines are coarse and conducive to inaccuracy, and the scales are susceptible to damage by abrasion and corrosion, said Mr. Kurtz. Advantage of magnification has been taken recently in the use of a glass scale, divided to fractions of a degree and a single line index by means of which angles may be estimated to 5 min. of arc. For linear measurements the scale is divided to read fractions of an inch, either by means of a single-line or an eye- piece micrometer. The scale is completely inclosed and protected from abrasion. The elimination of the vernier was stressed as reducing the setting and reading to the lowest terms of simplicity. A caliper made with such a scale was shown, also level protractor and devices for setting a milling machine indexing head. Other illustrations included thickness gages, by means of which thickness of 0.00005 in. may be read with cer- tainty, and a length comparator provided with two micrometer microscopes and capable of measuring to an accuracy of one micron or 1/25,000 in. In concluding his paper Mr. Kurtz said: “The success of such specially designed optical tools, to- gether with the obvious capabilities and possibilities for further uses of optical apparatus, indicate that much remains to be done before these possibilities are exhausted.” Among those taking part in the discussion were R. E. Flanders, manager Jones & Lamson Machine Co., Springfield, Vt.; G. M. Eaton, chief mechanical engi- neer Westinghouse Electric & Mfg. Co., East Pitts- burgh: W. J. Peets, engineer Singer Mfg. Co., Eliza- bethport, N. J.; C. W. Keuffel, Keuffel & Esser Co., New York, and D. R. Miller and H. W. Bearce, Bureau of Standards, Washington. Another paper at the same session was on “The Tension Ratio and Transmissive Power of Belts,” pre- sented by C. A. Norman, professor of machine design, Ohio State University. The paper gives in the form of curves the results of an investigation on rubber, Te ™ a tan rg a aes 1584 leather and fabric belts, conclusions drawn from the tests being given also. Loose Thinking in Design and Use of Engineering Products HE methods of the engineer in solving problems arising in the design of machinery, as contrasted with those who substitute guess work for analysis and chance for judgment, were outlined in a paper on “The Question Mark in Machine Design,” by Forrest E. Car- dullo, chief engineer, G. A. Gray Co., Cincinnati. The paper, which was read by A. L. Jenkins, professo1 of mechanical University of Cincinnati, Cincinnati, at a second held Dec. 2 under the auspices of the machine shop practice division, dealt also with the effects of loose thinking in the and use of engineering products. engineering, session erection The attitude of the average machinery user on the the method of attaching of foundations and on + subjec machinery to foundations was said to give some machinery builders a great deal of trouble. Machine frames, it was pointed out, are of two types: Those which have inherent rigidity and so have need of su} port at three points only; and those without inherent rigidity, which must be supported at intervals in orde to maintain their form and maintain alinement. At- tempts to confer rigidity on machines of the latter typ¢ by bolting or grouting them firmly to a foundation were said to be fatal to the satisfactory use of planers lathes and machines of that type. The bed of machine should be set on a good foundation, and sup- such a ported on suitable wedges or other leveling devices at intervals of 3 to 5 ft. Many shop men, said Mr Cardullo, assume that a foundation will remain true, and that if a machine bed without inherent rigidity be grouted to the foundation, it will add to the stiffness and strength of the bed and eliminate vibration. Foun dations sometimes settle from %4 to % in., a case being cited where planer beds were forcibly sprung over % in., by being firmly settled. Of the grouted to a foundation which had types of foundations, rock-supported. pile-supported, and floating, the rock-supported founda- tion was said to be the best machine foundation, if obtainable at cost. But this type 1s subject to some seasonable movement, and long beds or frames must not be grouted or bolted to it. Where the cannot be carried down to rock, it may be laid upon piles, columns or beams which are rock-sup- ported, such a foundation being less subject to seas- onal movement, but likely to settle at where it concentrated loads. three reasonapbie even foundation more ° pes carries Supporting Power of Floating Foundations The floating foundation, which is one laid on an ordinary earth surface and which has been properly leveled and compacted, must be stiff enough to transmit the load equally to all parts of the surface. It must also be large enough so that the distributed load does ot exceed the safe bearing power of the earth. It igned reinforced- persons mistak- of a floating and spend money s usually in the form of a properly des oncrete slak It said that many that the supporting powe1 s proportional to its depth, and was ingly imagine foundation unnecessarily for excavation concrete, or, Worse vet, erect n achin« ry on floating piers. It was pointed out that even a good floating foundation may settle and provision must st level. If the be made for keeping the machinery foundation carries only fixed it can support a number of machines with only slight seasonal changes and very little settling If, however, the loading varies time to time, as for instance, supports a column supporting a traveling crane, independent slabs should be provided for ma- chines without inherent rigidity, while a slab will do for a number of machines whose frames have in- weights, from if a slab common herent rigidity. When a floating foundation is laid near a pile or rock-supported foundation, many masons think that they add to the rigidity and supporting power of the floating foundation by anchoring it at this point to the pile or rock-supported foundation. As a matter of fact, said Mr. Cardullo, the foundation is then not so THE IRON December 10, 1925 AGE good as it would be if it were free from such support. It was pointed out that in this case, if the earth set- tles even slightly, the foundation will no longer be true: while if the rock-foundation be subject to moving loads, the floating slab will vary continually in its level. False Impressions Relating to Bearings A great deal of misinformation and false impres- sions were said to be current with regard to the design and use of bearings. The best bearing, where possible to use it, was said to be a perfectly cylindrical hole, the hole being larger than the shaft by an amount sufficient to permit an oil film of proper thickness. One of the things which is often done wrong is to “scrape in” or “fit” a bearing, “scraping in” being spoken of as the old-fashioned mechanical method of making a hole of the same size as the shaft. Therefore a bearing that has been scraped-in has no room between the shaft and box for an oil film. Half boxes were said to be often necessary in order to assemble the bearing, but in such a case the two half boxes should e machined to a perfect cylindrical hole and no shims should be used. The use of a “quarter-box” was char- acterized as a mechanical crime. In addition to being mechanically incorrect, the quarter-box was said to be an expensive form of bearing, and by substituting a properly designed half-box a great deal of bearing trouble will be eliminated. In referring briefly to lu- brication and oil grooving, Mr. Cardullo said that the figure eights, criss crosses and complicated systems of reversed spirals with which many bearings are pro- vided, show that their designers are ignorant on these points Another case of design error was said to be the open-side or G-frame for punches and similar machines. Gear Problems Discussed WO papers devoted to gear problems were pre- sented at this session, one being on the subgect of “Normal Pitch—the Index of Gear Performance,” by G. M. Eaton, chief mechanical engineer Westinghouse Electric & Mfg. Co., East Pittsburgh. Mr. Eaton’s paper, which was received with interest, outlined cer- tain departures from previously accepted practice, these departures being said to have been found use- ful in the manufacture of heavy involute gearing, as they ease the performance during the breaking-in stage of operation. The paper shows that improved per- formance may be obtained by adopting the proper re- lation between the normal pitches of the driving and driven gears, measured at the point of tooth engage- ment. A normal pitch indicating device was also de- scribed, this device having been improved, however, since the paper was written. The methods outlined were developed and are in commercial use at the R. D. Nuttall Co., Pittsburgh. They apply particularly to gears for heavy duty, such as those used in heavy traction electric locomotives. The fundamental prin- ciples, however, were said to apply to any involute gearing. Among those discussing Mr. Eaton’s paper were R. E. Flanders, manager Jones & Lamson Machine Co.. Springfield, Vt.; B. F. Waterman, engineer Brown & Sharpe Mfg. Co., Providence; W. H. Phillips, R. D. Nuttall Co., Pittsburgh; S. Timoshenko, research en- gineer Westinghouse Electric & Mfg. Co., East Pitts- burgh, and H. J. Eberhardt, Newark Gear Cutting Machine Co., Newark, N. J. The other paper devoted to gear problems dealt with: “Some Comparative Wear Experiments on Cast Iron Gear Teeth,” and was contributed jointly by Guido H. Marx, professor of machine design, Lawrence E, Cutter, associate professor of mechanical engineer- ing and B. M. Green, assistant professor of mechanical engineering of Stanford University, Palo Alto, Cal. The gears tested had a face-width of 1% in., all pinions having 30 teeth and all gears 60 teeth. Three types were included in the test; four-pitch, 14% deg. involute, standard depth; four-pitch, 20 deg. involute standard depth; and 4/5 pitch, 2 deg. involute stub- The test apparatus, which was designed by the tooth. Professor Cutter, was described, as was also December 10, 1925 method of making the test. Extended data and com- putations were omitted, and the results of the tests were set forth in the graphical form. Among the deductions indicated by the tests were: The standard depth, 20-deg. involute tooth form appears to be a better one to resist wear than the standard depth, 141% deg. involute form; the stub-tooth 20 deg. involute tooth form appears to resist wear better than the standard depth 14% deg. involute form and the standard depth THE IRON AGE 1585 20 deg. involute tooth form appears to resist wear bet- ter than the stub-tooth, 20 deg. involute form. The paper was read by W. R. Eckart, professor of mechanical engineering, Stanford University and among those discussing it were Wilfred Lewis, presi- dent Tabor Mfg. Co., Philadelphia; J. M. Lessells, re- search department Westinghouse Electric & Mfg. Co., East Pittsburgh, and C. W. Ham, associate professor of machine design University of Illinois, Urbana, IIl. Smelting Iron Ores Combustibility of Coke Studied by Bureau of Mines—Use of Manganiferous and Poor Alabama Ores WASHINGTON, Dec. 8.—With a view to increasing efficiency and lessening costs in the smelting of iron, the Bureau of Mines has attempted to determine the fundamental reactions (as in the combustion of coke) that take place in the interior of the commercial iron blast furnace. It has attacked the problem by two methods, says the report of the bureau for the fiscal year 1925. The two methods are: First, by studying the composition of gases between the tuyere level and the stock line; and second, by studying the composition of stock samples from various levels within the fur- nace. The investigation is analogous to work that the bureau has conducted with the small experimental fur- nace at Minneapolis. In a study of the combustibility of coke a survey was made of the combustion zones of 14 blast furnaces. Gas samples were taken at various intervals across the tuyere planes of commercial furnaces, and the bureau’s experimental furnace. Results of sampling at the tuyeres of 14 commercial furnaces, it is stated, show that the combustion of the coke in the hearth takes place in comparatively restricted zones at the nose of each tuyere. The results of sampling in the upper part of the stack of one commercial furnace, says the re- port, show that the movement of stock in the furnace is toward these combustion zones. It seems evident, it is pointed out, that the movement of stock and the process of reduction in the upper part of the blast fur- nace are not uniform; near the walls the charge moves faster than in the center of the furnace. In the blast furnace, the report states, the burning of the coke with pre-heated air at the blast entrance forms a 35 to 65 mixture of carbon monoxide and nitro- gen. This gas, forced upward through the furnace, heats the descending ore particles and reduces the iron oxide to metal. At the surface of contact between ore and gas, it is stated, three things happen: (1) Heat is transferred from the gas to the solid (2) The iron oxide is reduced through the oxida- tion of the carbon monoxide. (3) The gas pressure drops because of the surface friction. Knowledge of these three phenomena is of fundamental importance, and the North Central sta- ton is conducting laboratory experiments relating to them, “Formulas have been found by which the drop in gas pressure may be calculated for any given value of ore size, temperature, gas flow, and degree of packing,” the report says. “Experiments on heat transfer are giving promise. Studies on the rate of ore reduction show that although more than 99 per cent of the carbon monoxide can be oxidized by the ore and the reaction is rapid, the speed of the reaction is affected by the in- timacy of contact between gas and ore. A study of these three fundamental reactions will, it is hoped, enable the design and operation of the blast furnace to be less dependent upon rule-of-thumb methods and thereby the iron industry may meet better the increas- ing necessity of utilizing lower grades of ores and fuels.” Surveys in Alabama are declared to have shown vast quantities of iron ore that is of a grade too low for making iron under present conditions. The bene- ficiation of this ore to get a product that can be profit- ably smelted is being studied by the Southern station. In addition to a large number of small-scale tests, the station made many large-scale tests of samples of red hematite from the Birmingham district. The tests in- cluded gravity concentration, magnetic concentration, roasting, and microscopic examination. Good results were obtained from tests of ores from part of the gray iron ore mines in Alabama and a reasonably positive method of concentration was developed, it is stated. Samples of ore from Talladega district are to be tested. Use of Manganiferous Ores The report also deals with investigation at the ex- perimental furnace regarding the utilization of man- ganiferous iron ores. It is declared that steel makers and other users of manganese fully appreciate the lack of domestic reserves of high grade ore for ferromanga- nese. The primary object of the run of the furnace for a period of 34 days was to determine the feasibility of running a furnace on a 100 per cent charge of Cuyuna range manganiferous iron ores and to ascer- tain the tonnage, fuel consumption and recovery of manganese which may be expected in the commercial smelting of these ores. In treating of this subject the report adds, in part: During the test the composition of the slag was varied over a rather wide range and the effect upon the amount of manganese recovered in the metal was noted Cuyuna range ores give slags high in alumina and the test showed conclusively that such slags cause operating difficulties unless the basicity ratio of the charge is carefully adjusted to compensate for the Calculations made indicate that the recovery of manganese and the fuel consumption fall within the alumina range of commercial practice at furnaces making spiegel. One hundred and thirty-six tons of metal made during the tests is now available for investigating methods of obtaining a product that can be used in the manufacture of ferromanganese During the run nearly 900 gas samples were taken from various heights in the furnace From the more systematic and comprehensive data obtained, it will be possible to follow the reactions taking place within the furnace As similar data have been taken at a commercial furnace, comparisons can be made between experimental and commercial furnace conditions. Com- parison of gas analyses for the two furnaces indicates that interesting conclusions can be drawn concerning the paths of the materials within the furnaces A new style concrete board nail is being put on the market vy the American Steel Co., Ellwood City, Pa. A double head permits easy pulling of the nail without distortion of the lumber and this makes possible use of both the nails and the wood over again. In this line is also offered a nail that is finding large use in holding the false floor of automobile freight cars. The nail may be removed without destroying car floors. ey = é : eR Ls ES Ta Sulphur Taken Up from Fuel Gases* Absorption in the Open-Hearth from German Lignite Briquettes—Effect of Fluorspar and Ferromanganese INCE 19 the Peine rolling mills have used nsiderable quantity of lignite briquettes in the rotating-grate producers which supply the gas required for the open-hearth furnaces. At first bri quettes with a sulphur content of 3 to 4 per cent were ised, and subsequently the briquettes contained 2.4 to 2.8 per cent It was not possible to make exact measurements at ! s the sulphur content of the scrap used was wn; and, moreover, owing to irregularity the delivery of the briquettes it was seldom possible for any length of time on a single grade of briquettes They generally were mixed with a vari- able proportion of coal so that, for two furnaces whic! produced 35 to 38 tons per heat, there was one pr ducer operating on coal and four on briquettes. The sulphur content of the gases was determine quite regularly. The volatile sulphur in the briquettes ’ cen as being the difference between the total sul und the sulphur remaining in the ash. It has been assumed that only the volatile sulphur went off with the gases, the sulphate sulphur remaining behind n the ash; but it is not known for certain whether the sulphur is distributed in this manner, nor whether the ineration as carried out in the laboratory follows the Same course as the producer where moist air is introduced Determination of the sulphur contents of the bri- quettes and of the gas, taken in conjunction with the eld of gas per kilo of fuel, showed that the gas con- tained considerably more sulphur than would be the se if only the “volatile” sulphur of the lignite had een gasified; while with coal the reverse was true. That this is due to the use of steam rather than to a lag in the composition of the gas when there is a change in the fuel, was shown by the fact that, when no steam was used, the sulphur content of the gases ell to about 78 per cent of its former value. Most of e sulphur in the gases is in the form of hydrogen sulphide, and the presence of steam does not affect the proportion to any considerable extent. The sulphur content of the gas cannot, therefore, e calculated from the total and volatile sulphur con tents of the briquettes, as determined in the laboratory, because: (1) the ash from the producer has not the composition as the analytical ash, the former ng a certain amount of incompletely burned ( the yield of gas per kilo of lignite would have t e determined in each case, as the yield varies wit! he pitch content of the briquettes. The only accurate y } fi S pi i} 10 Ave ‘ got I { ret I t 0.0% { O.020 f 07 of 0.0 ‘ ‘ ( ‘ . . ,no7 i ( f 4, § ( 0.08 0.061 0.027 R §2 026 9 . 4 n¢6 4-1) O8 039 { ( 9 0. R¢ f { and satisfactory procedure is to make a determination of the sulphur in the gas. Use of Fluorspar The harmful action of the sulphur on the steel can be mitigated by the addition of fluorspar. The charge used during the period of the experiments consisted of: Cast iron, 10 to 11 tons; scrap iron, 26 to 28 tons; lime, 1.4 to 1.8 tons; 70 to 80 per cent ferromanganese, 120 to 300 kilos (added at the end) and fluorspar, 45 to 3 kilos per heat. The slag amounted to about 12 per cent of the weight of ingots obtained. The results of 144 heats are given in the table in order of descend- ng sulphur contents of the gas. The metal was sampled just before adding the ferro- manganese. In order to vary the basicity and the man- ganese content of the slag, heats were also run with ariable amounts of lime and of manganiferous sub- stances. A small number of flue gas analyses were made in the case of heats which received no fluorspar. It is difficult to conclude from the results if the metal absorbs more sulphur from the gases during or after fusion; but a previous test had shown this to be the case. When operating a single furnace with a mixture yf high-sulphur lignite br