Document QM0vNBaZy0Od5X38Djb6G9jL

FILE NAME: Garlock (GAR) DATE: 1936 Dec DOC#: GAR047 DOCUMENT DESCRIPTION: Trade Journal Article - Boiler Maker and Plate Fabricator Staybolt material in the storeroom represent!' * relatively amall cost per bolt. * * * Forger], threaded arid applied, as a replacem ent in. a locomotive, it represents m ore than a dollar in actual cost, * In m any cases the out-ofeervice cost for the locomotive must be added to this. * > ' Yet betw een the poorest staybolt material and the best there is a negligible difference in m aterial cost. ' " * The use of A gathon Alloy Staybolt? keeps renew al cost. at a, minimum . * " * A gathon Stayholt Steel has high tensile strength, high resistance to fatigue, and. high resistance to corrosion. " * It w ith stands the high pressures, the constant vibra tion and w eaving of the firebox. It g iv es longer service at Sower costs. * * Specify Agathon Staybob Steel for your difficult jobs. Complete details on request. A ddress D epartm ent BM. and finally THE SERVICE OF SUPPLY Large stock sheds as shown above are located at n\any convenient points throughout the eduntry. . ' Arch Brick supply is one of the most important items for economical locomotive operation. The American Arch Company, in maintaining an adequate stock of Security Arch Brick at many convenient points, recognizes its responsibility to the railroads. Stock sheds carrying ample stocks ready for immediate ship ment safeguard against delay. There's more to Security Arches Jhan ju s t brick This'facilitates locomotive arch maintenance and aids in maintaining maximum fuel economy. H ABBISO N-W ALK ER R EFR A C TO R IES CO. AM ERICAN ARCH CO. IU C O B P O B A IB L o c o m o tiv e (C o m b u s tio n R e fr a c to r y S p e c ia lis t S p e c ia lis t. * VOLUME XXXVI Published m onthly by Sim tnons-Boardm an P u blish in g Corporation, 1309 Noble Street, Philadelphia, Pa. E ntered as second a t the P o st Office a t Philadelphia, Pa., under th e A ct o f M arch 3, 1879. number Ia ss m atter, Jan u ary 5, 1W. Boiler M aker and Plate Fabricator N ew com ers in B oiler Field The steam generating plants, the Besler automatic boiler and the Steamotive, which are featured in two articles in this issue, open up a relatively new field for the utilization of the talents of the boiler maker. The trade in this country should be given due credit for its part in what appear to be the first conspicuous and practical applications of any great success made of the high-pressure quick-steaming boiler or generator of this type. It cannot be said that the basic ideas behind both types of steam generating plants are new or novel as both are refined developments of the flash boiler. How ever, the return of steam power to fields which here tofore appeared to be the exclusive property of Diesel power is definitely an event of considerable interest. The Besler boiler is an importation from Germany where the idea has been thoroughly tested. It appears to have many qualifications to recommend it for appli cation to existing equipment and to new trains. The Steamotive is a native development and is a slightly less ambitious undertaking as regards evapora tion rates, etc., than the Besler. The two types are sim ilar, however, in their marked departure from the more or less established practice and introduce other ideas into the field of steam boiler manufacture. Condition of tlie Industry While accurate statistics concerning employment in the various branches of the heavy plate industry are not available, it is probably true that not since 1928 or 1929 has a year closed with better prospects for the coming one from the standpoint of steady and remunerative work. There is nothing forced or artificial about the term in this connection, however, since it is only the natural result of a long period of curtailment in the demand for new power. The point has been reached where it is essential that the replacement program in every branch of the railroad industry be carried on at an accelerated pace. This condition extends throughout the entire maintenance and repair branches of the industry. In these columns last month attention of the supply trade, engaged in producing materials and auxiliary equipment, was directed to the possibility of using the facilities of this publication to better advantage in pre senting details of their products to the industry. By doing so a worthwhile service may he rendered to those whose duty it is to specify, select and eventuallv to apply such materials and equipment. Actually, a far broader field may he reached through this medium than the locomotive industry alone. 1'roduction and, consequently, employment in tin plate fabricating, have advanced and are still going for ward to meet the accelerated demands in these fields. During the past year these industries have enjoyed a level of business not equaled at any time in six years. N ovem ber R ecord Month for lo co m o tive Orders In the November issue of B oiler M aker a nd P late F abricator, comment was made on the encouraging indications of business recover)- in the locomotive manu facturing industry as shown by the relatively large number of steam locomotives ordered in the first ten months of 1936. This amounted to 143 units and before going to press, the report of an order for 20 by the Union Pacific in the first week of November was also published, making a grand total of 163 for the year up to that time. In November, in addition to the Union Pacific trans action, already mentioned, the New York Central Rail road placed an outstanding order for 100 steam loco motives, contracts being made with the American Loco motive Company and the Lima Locomotive Company for 50 each. The Chicago, Milwaukee, St. Paul & Pa cific ordered 30 locomotives from Baldwin and one from American Locomotive. The Chicago, Burlington & Quincy began the construction of 11 units in its own shops. This brought the total number of new steam lo comotives contracted for or ordered in the month of November to 162, which exceeds the total for the first ten months by 19. From the first of December to the-time of writing, 65 more locomotives have been ordered by American railroads. The Norfolk & Western is beginning in its shops the construction of 8 additional units of the 1200class articulated tvjie described in the Septeml" - issue, the Seaboard Air Line has ordered 5 from ` .aldwin and the Denver & Rio Grand Western has also placed an order for 15 with this company. The Wheeling & Lake Erie ordered 10 locomotives from the American Locomotive Company and the Atchison. Topeka & Santa Fe placed an order for 27 with the Baldwin Lo comotive Works. This surge of locomotive purchasing has not been unanticipated as the pressing need for locomotive re placement has been well known to all followers of railway affairs. It is known that the locomotive build ers have been preparing for the increased volume of business by rebuilding and reinforcing as much as pos sible the staffs and departments that were carried through the depression. It is feared, however, that the locomotive industry like other heavy industries which have suffered severe curtailment of activitv will be bard put to obtain the vitallv necessary experienced workmen and foremen for.efficient production and considerable training will have to be given new em ployes in order to bring the industrv up to its former jpearance somewhat comparable to the road's latest reamline coaches. The cars were stripped down, lowereck roof sheets and some details o f the old deck framig removed to save weight, and new carlines and roof beets applied from side plate to upper deck sheets to >rm a turtleback roof. On the power car a section 8 feet long at one end was eserved for application of the Besler boiler plant and uxiliary equipment. The entire length of 20 feet over he boiler room and baggage room bn the roof is taken ip by the condensers and exhaust steam-driven fans. A lumber of special details of construction had to be vorked out properly to carry the weight of condensers und fans and also maintain the necessary strength across he sides of the car. The necessary control apparatus vas applied in each compartment and the train is operited in either direction without turning. The old truck under the boiler end of the power car was replaced by the Besler power truck, all other trucks remaining the same. Fuel and water tanks of 500 gallons capacity each were applied to the power car. The tars were semi-permanently connected together, the old couplers and draft gears being retained. The overall length of the power truck is 17 feet 8 inches, and the total width over the cylinder lagging cover is 9 feet 5 inches. The wheelbase is 11 feet 6 inches and Bethlehem low-carbon molybdenum wheels with chrome vanadium axles are used. The total weight of the power truck is 35,000 pounds. There are two direct, two-cylinder compound engines, each having cranks pressed onto extensions of the axle stub outside of the journal bearings. The high-pressure cylinder is 6 inches in diameter and the low-pressure cylinder is 11 inches in diameter. Both cylinders have 9inch stroke. These are conventional double-acting com pound engines, with piston valves. The crossheads are cylindrical in shape and are made of cast steel with babbitted shoes. All bearings are of the roller type throughout and all working parts are machined all over. The valve mechanism is a Stephenson link motion arranged to be operated pneumatically to give two posi tions forward and two positions reversed. The lubrica- Steam generator as set np in the laboratory for testing showing compactness of the Besler unit for railroad service Top view of the power trade showing the truck and engineframe castings as well as the brake and spring arrangement The Besler fwo-car steam train on the New Haven New Haven steam rail train features BESLER A U T O M A T IC B O ILE R The New York, New Haven & Hartford now has in service, between Bridgeport, Conn., and Hartford, a two- car steam-powered rail train equipped with the Besler steam power plant. This train is operated in almost con tinuous service from 6:00 a.m. to 10:20 p.m. making six trips of 31.9 miles between Bridgeport and Waterbury and one round trip of 125.86 miles between Bridgeport and Hartford each day, giving a total daily mileage of 317.26. When it was first decided by the New Haven to use a Besler power plant the idea was to make the most econom ical possible application, from the standpoint of initial investment, in order to be able to demonstrate in ser vice the capabilities and reliability of the equipment. This would involve simply the application, to two existing coaches, of the power truck, boiler, condensers and con trol equipment, together with the operating compartments at the ends of the train. A preliminary consideration of this idea, however, indicated. that a much better job could be done by a complete rebuilding and remodeling of the two coaches at a comparatively small increase in cost. / As finally completed, loaded with fuel and water ready to run, the weight of the train is 303,600 pounds. The two steel coaches which were converted into this train had a weight of 258,400 pounds The application of the Besler power plant and the modernizing of the two cars, plus fuel and water and air conditioning equipment, therefore has only added 45,200 pounds to the weight of the original equipment. With 500 horsepower available at the rail the Besler train, ready to run, has a horse- N ote:-- T his article is based on papers presented before the New Yorlt R ailro ad C lub, O ctober 16, 1936, by K. C artw rig h t, N . Y ., N . H . & H . (describing the tra in ), and George D. and W illiam J. B esler (describing the power p lan t), supplem ented by additional details concerning the boiler. T h ere is also included a sum m ary of questions raised d u rin g the discus* sion following the presentation of the two papers. power-weight ratio of 607 pounds (3.3 horsepower pe ton). By comparison the New Haven Comet, loadec with fuel and water ready to run, weighs 260,590 pounds This is powered with two 400-horsepower Diesel engines giving a total of 800 horsepower. If, however, all aux iliary equipment is in operation at once, considering the efficiency of the electric drive, a maximum of 600 horse power is available at the rail. This gives a horsepowerweight ratio of 434 pounds (4.6 horsepower per to n ). If, instead of applying the Besler power plant in the older steel coaches as was done in this case, such a power plant were applied to two of the modern New Haven light-weight streamline coaches, it is reasonable to expect that a two-car train could be built with a total weight, ready to run, of approximately 250,000 pounds. This would have a horsepower-weight ratio of 500 pounds (4 horsepower per ton). Two old New Haven steel coaches, approximately 20 years old, were selected and designs worked out for re modeling them by the application of the Besler power plant and other modifications into a modem appearing streamline train. These old cars were of the monitorroom construction, with narrow letter boards. As re modeled the exterior was changed to give an outside Characteristics of Besler Train and The Comet T o tal horsepow er V.................................. H orsepow er a t rail ............... . ............... .. Seating c a p a c ity ............................................... Baggage capacity ............................................. O verall length, ft. and in ............................. .. T o tal weight-, ready to ru n , lb. .................. D istributed w eight, pow er tru c k , lb ........... T ra ile r tru c k pow er c a r, l b . ......................... T ra ile r, inside tru ck , lb ................................. T railer, leading tru c k . I b . .............................. W eight light tra in , lb....................................... W eight pow er plant and control, lb ........... Besler train 600 550 152 12 ft.-- 3,0001b. 163-- V /t 306,600 104,000 67,000 65,000 67,600 296,100 32,700 (approx.) T he Comet 800 590 (rain.) 160 None 207-- 0 260,590 86,835 43,890 44,375 85,490 248,590 71,039 324 Half section of the Besler Uniflow boiler tion is accomplished by splash within a sealed crankcase, and a circulating plunger pump is furnished to assure lubrication at slow speeds. The cylinder relief valves are air operated. The engine is designed for a steam pressure of 1500 pounds per square inch and, at 1200 pound inlet pressure, the truck has an average starting tractive force of 15.000 pounds. The truck is rated at 1000 horsepower, although it is capable of producing more than this with sufficient boiler capacity. The boiler is of the continuous-flow, non-water level type, having no drums or headers. The general arrange ment of the coils in the boiler is shown in an accompany ing drawing. The tubes in the coils, vary in diameter from y, inch in the top rows to 2j4 inches diameter, in the superheater section. The water enters the top of the boiler, passing down through the pancake coils where it is heated in the coils in the top six-coil sections. In the next lower six-coil sections the water is gradually changed to steam. Having reached a point in the boiler directly above the superheater coils, the saturated steam passes through a tube, indicated by the arrows in the drawing, to the outside of the boiler through which it is taken to the top of the coil group which entirely sur rounds the side walls and bottorh of the combustion chamber. The steam in working its way through these coils passes down alternate rows to the bottom coil underneath the combustion chamber. Having completed a circuit in the bottom coil, it passes up other alternate rows of tubes to a point at the top of the combustion chamber where it enters the bottom of a seven-tube coil immediately under the superheater section. After pass ing through this section it goes into the superheater sec tion composed of five rows of header type coils. The superheater coils are U-shaped in arrangement with the l.w.lj cuu di which clean-oui nanu-noie plates are fitted to the boiler shell. The formation of scale in this type boiler is confined to the superheater section and the clean-out hand-holes are provided to facilitate the use of a mechanical cleaner in the super heater tubes. The entire boiler is encased in an airtight sheet-steel housing with 2 inches of insulation between the inner and outer casings. The inner casing is con structed of corrosion-resisting Inconel and the outer casing, separated from the inner casing by insulating brick, is made of sheet iron. The boiler is equipped with fully automatic safetv devices to protect it against empty water tanks or other contingencies. The burner is the pressure atomizing type of Besler design and construction. It automatically meters the fuel in proportion to the flow of air which is delivered bv a multivane type blower. Adjustment is not necessary because of a change of altitude or a change in draft pressure, and the burner automatically compensates for changes in air flow caused by entering tunnels, high speeds, or cross winds--in every case metering the cor rect amount of fuel. The burner operates fullv on or off. Ignition is secured by a high-tension electric spark. The auxiliaries are driven by a two-cylinder. 90-degree V-tvpe double-acting steam engine. The water pump drives are integral with the main crank shaft. The auxil iary steam engine drives the electric generator through V-belts. The generator supplies current for lighting, ventilating and for the requirements of the power plant. The auxiliary engine also drives the air compressor and the forced-feed main-engine lubricators. It operates at a back pressure and exhausts into the train-heating line. When train-heating is employed the power used to drive the auxiliaries represents only two percent of the boiler output. The condensers are of the fin and tube type, placed on the roof of the car. Propellor type fans driven by individual exhaust-steam turbines of our own design and manufacture are located adjacent to the condenser cores on the roof and draw air through the cores, discharging it upward. The turbine speed inherently varies in proportion to the steam flow, producing the optimum relation between air flow and condenser load at all outputs. Schematic diagram showing the relation and functioning of the various {arts of the equipment ...-- ii i reserve |x>wer truck were available, it would merely be a problem of lifting the car. rolling the new truck in, dropping the car and making the various steam and air connections. 23. Q.--is the boiler operated at constant pressure? A.--No attempt is made to maintain constant pressure. The boiler operates at a constant superheating outlet temperature. A constant temperature is maintained, as that is what determines proper lubrication and ef ficiency. 24. Q.--Is the lubricating oil atomized into the cyl inders or fed onto the cylinder walls? A.-- It is fed into the valve chamber and atomized by the velocity of the steam. 25. Q.--l['hat is the fuel consumption per hour? A.--One pound of fuel per horsepower hour. 26. Q.-- ll'hcn the train is operated by means o f the controls at the opposite end from the power unit, zvhat controls and what gages does the operator have for feedwater for the boiler? A.--The controls consist of a throttle, air-brake valve and reverse mechanism. There is nothing to indicate to the operator what is going on at the power plant, as the operation of the boiler is entirely automatic. 27. Q.-- 11'hat type of a transmission is used? A.-- There is no transmission. The steam engine connect ing rods are directly connected to cranks which are pressed on to an extension of the axles. It is interesting to note that there is not a single gear of any description on these two cars. 28. Q.--Hose is the control operated from the oppo site end of the train? A.--Pneumatically. 29. O.-- What is the storage capacity of the boiler? A.--Only enough to go about half a mile. Storage ca pacity is not carried in the boiler water, but in the hot tubes. As the pressure drops an additional quantity of water comes from the economizer section of the boiler, and in contacting the hot tubing it generates steam which gives this boiler its amazing reserve capacity. 30. Q.--Hose long does it take to get the boiler hot from cold zeafer? A.--The rail car is able to get steam up in an average time of five minutes from dead cold. It cannot be operated in five minutes, however, because of the necessity of pumping up air for about 12 minutes. The time required from stone cold to the point where it is ready for operation depends upon the time required to pump up air. As far as the boiler is concerned, working steam pressure can be built up in approximately 3Y\ to 4 minutes from the time the fire is started. M achine-M ade Jobs and Present Em ploym ent Major industries which have instituted the greatest technological changes in the last few years have added millions of wage earners to their payrolls and many of them employ more workers today than in 1929, accord ing to a study made by the Machinery Institute and re ported recently in a pamphlet "Machine-Made Jobs." The report is the third of a series by the Institute, of which John W. O 'Leary is president, giving factual evi dence that jobs are created by the advance of science and invention. The contents are "buts and ands that must be considered in connection with common statements which on the surface appear to prove that machines cause unemployment." "Vast technological improvements have been made in the automobile industry, which have greatly increased productive capacity of workers in many jobs," says the pamphlet. " But employment per vehicle manufacture was 25 percent higher in 1935 than in 1929. And la: year 109 workers had jobs making automobiles for ever 100 between 1923 and 1925." It deals with many of the leading industries in whic machine developments are often accused of having de stroyed employment opportunities. Among the fact presented are: Telephone girls increased by more than 50,000 during the ten years that the dial system was being installed, anc linemen increased 100 percent. Ice dealers more than doubled between 1920 and 193C because mechanical refrigerators popularized all refrig eration. It takes far more workers to furnish the textile de mands of a thousand Americans today than it did in the colonial days of spinning wheels, due to increased use of textile products as a result of lower prices when machine methods are used. Machines have revolutionized office work in recent years, yet stenographers and typists increased 32 percent and bookkeepers, cashiers and accountants increased 27 percent between the last two census years. Population increased only 16 percent. Sound pictures displaced 50 percent of all theater mu sicians, but during the same years musicians and teachers of music increased by 35,000, actors by 17,000, theater ushers by 7000 and radio employes by 15,000. A printer today can set more than five times as much type as one without a linotype did in 1890, yet there are five times as many employed in the industry as there were then !recause machinery has lowered prices and made possible the vast growth of the printing and pub lishing business. " Some of the greatest technological developments in America in recent years have taken place in the iron and steel industries,'' says the pamphlet. "But the use of steel in the United States increased from 2600 nounds per person in 1900 to 16,800 pounds in 1935. There used to be only two or three kinds of steel, but today there are about 10,000 different specifi cations as to alloys, sizes, finishes and shapes that mod ern industry demands. "And employment has grown from less than 150,000 sixty years ago to about a half million today, and despite, or because of, the recent technological changes employ ment in 1936 passed the 1929 peak. Production is far below capacity and with its inevitable rise employment will go even higher." The employment of both women and children in man ufacturing industries has declined during the last genera tion while mechanization has been greatest, and the em ployment of men in manufacturing and mechanical in dustries has more than doubled since 1890, according to the Institute. Wage and salary earners get a larger per centage of the national income today than ever before, largely because machinery Has increased workers' pro ductive capacity and earning power. Western Bailer Maker Dies Richard J. O'Neill, former national president of the Boiler Makers' Association of America, died November 12 at his home in Denver, Colo. He was 78 years of age. Mr. O'Neill had been employed by railroads in every part of the United States. Forty years ago he built the first camel-backed locomotive in Rawlins, Wyo. He first came to'Colorado in 1904 to accept a position with the Colorado & Southern Railroad. At the time of his retirement he was general foreman boiler maker for that road. > 328 Steamotive unit on flat car ready for shipment Steam otive-- A M odern Pow er Unit The design and testing of a new type of steam-generating unit of good efficiency, relatively light in weight and requiring a minimum of space, was described jointly by the General Electric, Babcock & Wilcox, and Bailey Meter companies at the annual meeting of the American Society of Mechanical Engineers, in New York City, November 30, by E. G. Bailey of the Babcock & Wilcox Company. A. K. Smith of the General Electric Com pany, and P. S. Dickey of the Bailey Meter Company presented the paper at the meeting. The new type of steam-generating equipment has been named the Steamotive. In it, steam is generated at high pressure and tem perature: and fully automatic control in response to changes in demand has been incorporated. The units are intended for capacities of from 2000 to 10,000 horsepower. Two such units have already been built. The first, now in service in the Lynn, Mass., works of the General Electric Company, is used to test marine and other small turbines. It has an output of 21,000 pounds of steam per hour at a pressure of 1500 pounds per square inch. Another, a completely co-ordinated power-generating plant incorporating the Steamotive and turbine-genera tor. with a capacity of 10,000 jxtunds j^er hour and furnishing steam to a turbine at 1200 pnmds per square inch and 950 degrees F.. is being installed in a small, isolated plant of a large industrial concern to supply electric power and low-pressure steam for building heating. Both are oil-fired. Two oil-fired Steamotive units, each with a capacity of 40,000 pounds per hour, are now being constructed for the Union Pacific Railroad for driving two 2500- horsepower electric locomotives, it was announced at the meeting. These units will furnish steam to the turbines at 1500 pounds per square inch and 950 degrees F. Indicating the compactness of the Steamotive unit, the one for Lynn was shipped complete from Schenectady on a railroad'flatcar. Objectives sought in the design of the new equipment were pointed out by the speakers as high steam pressure and temperature, minimum weight and size per unit of steam produced, wide range of capacity with ability of the unit to respond quickly to wide variations in load conditions, adaptability to wide range of fuels, com pletely co-ordinated auxiliaries, completely co-ordinated automatic control, and units of simple design and con structed in sizes small enough to be portable. Answering these s]>ecifications. the Steamotive boiler was designed and built by The Babcock & Wilcox Com pany at Barberton, O. The meters and complete automatic control were designed and built by Bailey Meter Company, Cleveland. The auxiliaries which sup ply fuel, air, and feed water are controlled in accordance 329 A u x ilia r y S z t Drive?. Turb*>C Stccm O u tp u t R cgu lati ng V a iv i \ Steam P ressure Co ntroller Hicjh P re s s u re Tri p Steam Tem perature Indicato r High Tern pe r a t u rv T r.; Drum Level___ C o n tro lle r SIntedaicmatFolro w ____ 0*1 How An' FlOw^-- Controllc r Drivi T u rb in e Stem Valve O p e ra to r Automatic L ig h t in g tq-.Hpm apt .w' r n o r C c n t r o i r - d i t f " d ' J - i-.'r H igh P re ssu re Surge Cham ber B o ile r Feed Pump Fuel OH Rump F u e l OH cm pc ratu re C ontrol F u OH H ju te r Fuel OH a n ut o ff Valve fo r Automatic Light ing Equipm ent General view of generating unit now in commercial service at the Lynn, Mass . works of the General Elec tric Company for testing uti'Oi V.- l-"in`j Of T, with demand- for Complete automatic ignition and safety equipment are included. The auxiliary set was designed and i>uih ltv the (General Flectrie Company, which company al>o did the assembly work ot the complete uni: a: it- Schenectady plant. 'Idle auxiliaries, geared together a- one tarbine- driven unit, in the ease of the unit at Lurn on>i>t uf a teed pump delivering 25.000 pound.- of water per hour at a pressure of 2000 pounds, a blower lor 20.000 pounds of air per hour at dO-inch water pre-.-urc. a fuel-oil pump, and a lubricatin^-oil pump. The complete Steamotive unit was designed and constructed -o as to he suitable for installatimi in a Connotivi- in emihntcnmt with ti l'-oinc- electric drivi- instailol In' i ;u- t irncra'! Idr e- ac ( u-; :prmv. In tin- iipi-ratii m ni the Stcatm m o mut, the literK- nudi na-i-s ; a-- i''i nn tin harm r \ O.e 'h-n-l\ n an '' v.>' ! tnrnacc. !<-tnv ::a : on i ' : -win ar. .-.ml I' a- -c] laratm . 11 ;-i i :' c t u r d ao heater, ana up the .tack. i a ar.' " o o f a n .cm r- th e liluwcr at rclattveh inch |>v<--i:,v I1--.e 11c ' *>iuy1 lanes intersecting tin- slack, ami A wn ar- -mal :: if air- licaii-r till-' n> the m'l hnrmr. T ! ; r i a i- no italno draft fan. tlic hi wer irn'cnm; pu- air thru neb d.: ' hunt rr and furnace mi'liT pressure. "1lie Icol water enters the eemiinnizer mie t Itetele r. and. after leavhtc the mulet header. i- dl\ ulol tnlu -cvcrai eirenits, all uf which form the Hum-. sale. . ami ; 111if of the luniacc, as well a> the sti- a' leap. ;iimu ay tIn huiler screen. All the steam, t- imm r; wd m diem !uma re and limier circuit'. ami . nmr~ : , -1 jsoai'C, oidi a surplus m water m each circuit. f ;h*iii ?A- ' ``I'araior. the <lrv steam ^ue- thrmicii the >ti|>e rheau-r . and ciuvctU to the main turbine. The water from tin- -eparator is called the -pillover. and it p a .w- through a h `-at e x changer to the hot well, where it mixes with the condensate, and is refed to the boiler hv the teed pump. Due to the compact arrangement of the Steamotive unit, it constitutes what is practically a packaged power plant. " Tests made on the developmental Steamotive unit and subsequent design studies indicate tliat a -team- yeneratiny unit of this tvpr is entirclv practical for yener- ation ot hiyh-pcessure and hiyh-temperaiure steam." i: was rep-orted at the meeting. " The principal advantageof tins tyj)e of unit over natural-circulation boiler installations are the small -pace required and the reduc tion in weight ot the unit i For example, in locomotives it is po>-ihle to tit this type of boiler into a restricted space and the design is flexible in im adaptability limits in height, width, or length. Diagrammatic layout of Steamotive unit at Lynn aftercooler and the piping was tested at intervals in the interest of safety. After the accident double extra heavy pipe of inch thickness was installed, and to minimize the possibility of a similar occurrence an oil separator was placed between the after cooler and the receiver. It also was advised that oil being fed to the compressor be kept at an absolute minimum. The other accident occurred to piping used in connec tion with air hammers at a Pennsylvania steel mill. When the air line broke, an air receiver toppled over on a workman with fatal results.-- The Locomotive. and weighing approximately 10 tons. This is thought to be the tallest pre-fabricated steel stack ever erected. The stack is anchored to the floor and roof of the boiler house, which reduces its outside height to 83 feet. A portable tractor-powered crane of all-welded design was built to lift and place this stack and for other heavv duty. To erect this stack, a feat which was performed in 30 minutes, the crane was equipped with an 84-foot boom. It is reversible, however, the boom becoming a tongue and the 22-foot tongue a boom, which gives it a 40-ton capacity. All-w elded Sm oke Stack Erected In building a plant to heat its factory at Peoria, 111., R. G. Le Tourneau, Inc., manufacturers of heavy grad ing equipment, were confronted with the problem of constructing and erecting a smokestack tall enough to carry the smoke clear. Inside the plant, inch plate was pre-fabricated into an all-welded stack 104 feet high, 57 inches in diameter ______ . . . -- Income D erived from M anufacturing Manufacturing is the largest industrial source of the national income, generally contributing 20 percent to 25 percent of the total, according to a study just published by the National Industrial Conference Board. In 1935, the board estimates receipts from manufacturing in sal aries, wages, dividends, interest, and other payments at $12 billion. The Conference Board's study makes available for the first time estimates of income from manufacturing in each of the individual states. Other studies will be ready shortly giving income by states. Income from manufacturing was a little over $18 bil lion in 1929, but dropped rapidly with the advent of the depression and in 1932 and 1933 was less than $8.5 bil lion. From this low point it has risen steadily. Pre liminary indications are that a substantial gain will Ire recorded for 1936. Approximately three-fourths of the total income from manufacturing, the Conference Board points out, is received in the northeastern section of the United States. Of the total estimated income for 1935, the Middle Atlantic states received 34 percent, the East North Central states 30 percent, and the New England states 11.5 percent. New York alone received $2,014 million, or 17 percent of the total. Pennsylvania, the second largest manufacturing state, received an estimated SI. 352 million, or nearlv 12 jtercent of the total. Salaries and wages are by far the largest single t\pe of income contributed bv manufacturing industry and account for 80 percent to 85 percent of the total. Di vidends, the second largest t_\q>e of payment, account for 12 percent to 15 percent of the total. The remaining 4 percent or 5 jtercent of income from manufacturing is made up of entrepreneurial income, interest, and net rent. . Hoisting all-welded stack into position Xew Line <f Eleetrodes Announeed Metal & Thermit Corporation, 120 Broadway, New York, announces an addition to its line of Murex heavy coated electrodes for arc-welding. The new electrode, known as Murex Type N, is de signed for bridging gaps where fit-up between plates is poor and, in the smaller sizes, may be used on vertical and overhead work, or to make rapid, single pass welds on light-gage materials. The physical properties of the metal deposited by this electrode are said to range from 74,000 to 84,000 pounds per square inch in tensile strength, with 26 percent to 24 percent ductility. Tire new electrode is also said to work equally well with either direct current or alternating current and may be used either with straight or reversed polarity. AjpyHwrtioa mf o i e r r iw to Vessels Under External Pressure' The action of a vessel under external pressure is dif ferent, in many respects, from its action under internal pressure. A vessel under internal pressure, is, for the most part, under tensile stress and it tends to change to a shape of greater strength. That is to say, a cyl indrical vessel under internal pressure tends to take the shape of a sphere and would do so if the material were sufficiently ductile. On the other hand, a vessel under external pressure tends to change to a weaker shape. As the change in shape occurs, its resistance to such change is very much reduced and failure takes place rapidly at a pressure even less than the vessel could safely with stand in its original form. The action of vessels under either internal or external pressure may be compared to the action of test speci mens of steel under tensile stress or under compression. The material in the shell of a vessel under internal pres sure acts in the same manner as a specimen under ten- Fig. 1 sion. A vessel under external pressure acts in a manner quite similar to a specimen under compression. This comparison of the effect of external pressure may be carried a little further by considering the action of long and short specimens under compression. Specimens in which the thickness or diameter is small as compared with the length will, under compression, tend to bend easily. Some bending may take place before the stresses reach the yield point or elastic limit of the material. If, when a certain amount of deflection has occurred, and before the yield point of the material is reached, the load is removed, the specimen will return or spring back to its original condition. However, when the specimen bends, it immediately loses strength, it very soon passes the yield point and, hecause of the change in shape, the continued applica- B y \Y. D . H a l s e y ** tion of the load will cause it to fail. Specimens which have a large thickness or diameter as compared to their length will not bend under a compressive load but will upset or change shape by increasing in diameter or cross section. A specimen in which the thickness or diameter is small as compared with the length is said to fail by "instabil ity." On the other hand, a specimen that has a large diameter as compared with the length is said to fail by "yielding." Pressure vessels under external pressure may fail in either of these ways. The ratio of plate thickness to diameter and also the ratio of the length of cylinder to diameter are very im portant in the analysis of vessels subject to external pressure and will be extensively used in this discussion. Vessels with walls that are relatively thin as com pared to the shell diameter change shape readily under external pressure and, by such action, become weaker and deflect still further from the original shape. How ever, until actual permanent change in shape takes place the stresses in the material do not reach the yield point. Such vessels are said to fail by instability. Other vessels which have walls that are relatively thick as compared with the shell diameter do not fail until the stresses in the material reach the yield point. They then start to deflect and thus become progressively weaker. The yield strength of a short thick column is easy to calculate, it being simply a matter of dividing the load by the cross sectional area of the specimen. It is also easy to cal culate the strength of a vessel that will fail by yielding, as the computation is the same as that used for vessels under internal pressure. However, just as the strength of a slender column depends upon its length and its crosssectional dimensions, so also does the strength of a ves sel, that has a thickness small in comparison with its diameter, depend upon its length, thickness, diameter, and, of course, upon the physical properties of the material. In a cylindrical vessel under external pressure, the heads, by maintaining the circular shape of the vessel at its ends, tend also to strengthen the entire structure. Therefore, the distance between the heads, or supporting rings, of a vessel enters into the determination of its strength. On the other hand, when the length of a vessel reaches a certain point the heads no longer help support the middle portion, so that the collapsing pressure re mains unchanged for any further increase in length. The calculation of vessels under external pressure in volves some very complex mathematics. The new rules for external pressures in the Unfired Pressure Vessel * A bstract of paper presented at the tenth annual meeting of the National Board of Boiler and Pressure Vessel Inspectors. ** A ssistant c h ie f engineer, Boiler D ivision, H a rtfo rd Steam Boiler Inspection and Insurance Company. ' 333 334 Boiler Maker and Plate Fabricator Fig. 2 Code of the American Society of Mechanical Engineers relate only to vessels of the three general types shown in Fig. 1 and only when they are built of ordinary boiler steel or material having practically the same physical properties. The vessel (A ) in Fig. 1 will be recognized as a plain cylindrical vessel which might be used as a vacuum tank, the external pressure being only that of the atmosphere. (B ) Fig. 1. represents the typical, cylindrical, jacketed vessel or autoclave. (C) Fig. 1 is a type of vessel, ex tensively used, of which a fat melter in the packing in dustry is typical. It has been found by experiment that vessels having the same ratios of length to diameter and of thickness to diameter will collapse at the same pres sure. For instance, two vessels, one of which is 100 inches diameter, 200 feet long, of 1-inch plate, the o th e r 50 inches diameter, 100 feet long and y i-inch plate have the same collapsing pressure, the t/D and L /D in each case being 0.01 and 2 respectively. Because of the fact that the thickness, diameter and length of a vessel all enter into the computation for its strength, and in a very involved manner, it has been found convenient to refer to the t/D and L /D ratios rather than the actual values of thickness, diameter and length. Furthermore, since the mathematics involved in making calculations are very complex, charts have been devised to make easier the solution of any given problem. The chart applying to cylindrical vessels of the three types shown in Fig. 1, when constructed of ordinary boiler steel or similar material, is given in Fig. 2. The extreme right-hand side of this chart applies to those vessels which have a great length as compared to the diameter. That is to say, the L /D ratio is high and in such vessels the ends do not give any support to the middle section. Therefore, the collapsing pressure of the safe working pressure is independent of their length. The middle section of the chart where the lines are diag onal represents those vessels in which the strength is affected by the length. It will be noted that as the ratio of length to diameter decreases, the working pressure increases. At the left-hand side of the chart the lines again be come horizontal. This section represents those vessels that fail because of yielding of the material irrespective of the strength afforded by the heads or supporting rings. That is to say, as a design is shortened in length, a point is reached where failure will occur in the same way as a short column. Just as with a short column, where the December, 1936 335 strength remains the same regardless of its length, the design of a cylindrical vessel reaches a point where fail ure will occur by yielding and the collapsing pressure or safe working pressure is not changed by designing a shorter vessel. Just for a moment, take a vessel which has a length twice as great as its diameter. With a given thickness and a given diameter that vessel at t/D ratio 0.8 would have an allowable pressure of 45 pounds. If that vessel were twice as long, in other words the length were 4 times the diameter and the L /D ratio up to the 0.8 line, we would find the allowable pressure is 22 pounds. When we make the vessel longer the heads do not give the same support as they did when they were closer together, and therefore there is a lower safe working pressure on those vessels. So that you see the length and the diam eter length ratio of a vessel under external pressure are very important whereas they have no bearing on a vessel under internal pressure. In the calculation of a vessel under external pressure, the length may be taken as the difference between any two points where the support is sufficient adequately to hold the vessel in circular form. The heads on a vessel whether flat, d i s h e d , or hemispherical, are considered to be adequate supports of this nature. For heads that are riveted to the shell, the length of the vessel may be taken as the distance between the head seams. In the case of heads butt welded to the shell, the length should be taken as the distance between the points where the curva ture of the heads begin. Supporting rings may be attached to vessels under ex ternal pressure and, provided they are of adequate strength, the length L may he taken as the distance between such supports. The method for determining whether r i n g supports are adequate will be discussed- later. To illustrate the distance that is to be taken as L in the application of this chart, a few typical constructions are shown in Fig. 3. In the lower left-hand sketch of this figure, several designs of re inforcing rings, and possible methods of attachment are shown. Although the rules given in the A.S.M.E. Code for ves sels subjected to external pressure are primarily in tended for the guidance of designers these rules may also be used to determine whether a vessel already in use has been properly designed and whether it is adequate for the pressure to which it is subjected. The simplest illustration of a vessel under external pres sure is a vacuum tank. As a typical case, assume a tank of riveted construction, with butt type longitudinal joints, a diameter of 5 feet, a length of 20 feet between the head seams and a thick ness of the shell plate of x/ i inch. In this vessel the L /D ratio is 20/5 or 4. The t/D ratio is 0.5/60 or 0.00833. Carefully note that both the fig. 5 Boiler Maker and Plate Fabricator numerator and the denominator of these ratios must be given in the same units of measurements, that is, both must be in inches or both in feet. Referring to the chart, Fig. 2, find the vertical line marked "4" representing the L /D ratio of that amount. Follow vertically on this line to the line representing a t/D ratio of 0.00833. While there is actually no such line, there is one for 0.008 and one for 0.009, so that the line for 0.00833 would be about one-third the distance be tween the two or approximately at 25 pounds, and the vessel would be adapted to that pressure. It is evident, therefore, that the vessel is entirely satisfactory for use as a vacuum vessel which is subjected to only 15 pounds external pressure. The question may be asked how thin a vessel 5 feet in diameter and 20 feet in length, may be and still be satisfactory for use as a vacuum tank. At the bottom of the chart find the horizontal line for 15 pounds pressure and note that the vertical line for L /D crosses this 15 pound line a short distance to the left of the t/D line for 0.007, Estimating the distance between the t/D line 0.006 and that for 0.007 it will be found that the L /D line 4 crosses the 15-pound line at a t/D value of 0.0069. In other words, the vessel in question should have a t/D ratio of 0.0069. If the ratio of t/D is 0.0069 then the thickness will be that ratio multiplied by the diameter. In other words, if t/D = 0.0069 then t = 0.0069 X D and since D is 60 inches t = 0.0069 X 60 = 0.414 inch As a second illustrative example, consider a jacketed autoclave, as shown at the upper right corner of Fig. 3, with a diameter of 45 inches, a length of 36 inches, and a thickness of inch or 0.4375 inch. The desired working pressure is 140 pounds per square inch, but it is not certain that the thickness is sufficient. In this case the L /D ratio is 36/45 or 0.8, and the t/D ratio is 0.4375/45 or 0.0097. Following up the vertical line 0.8. to a point were a line for a t/D ratio of 0.0097 might be drawn, it will be found that the allowable pressure would be only slightly more than 100 pounds. Continuing up the line 0.8 to the 140- pound line, it will lie found that the required t/D value is approximately 0.0135. Since the diameter is 45 inches, the required thickness should be 45 X 0.0135 or 0.608 inch thus showing that the original thickness of Vie was not sufficient. It has been stated previously that if supporting rings attached to vessels are of adequate strength the length L may be taken as the distance be tween such rings. The question arises as to just what constitutes adequate strength. It will be recognized that the required size of support ing rings depends upon the outside diameter of the ves sel, the length between the stiffening rings, and the work ing pressure. The size of such rings may be determined by the application of a theoretical formula relating to the buckling of circular rings under uniform external pres sure. However, this formula is somewhat difficult to use and it seems best, both for the purpose of clarification of the matter and for readiness of application of the code, to obtain the required size of such rings from a chart which is shown in Fig. 4. In applying this chart from a design standpoint, the product of the length, in inches between the centers of the stiffening rings and the working pressure is calcu lated and the line representing this product is located on the side of the chart. Follow horizontally along this line until the vertical line representing the outside diameter of in - - 1 - 1' * of these horizontal and vertical lines there will be found the value for the required moment of inertia of the stif fening rings. For the purpose of illustration, consider the vacuum vessel 5 feet in diameter and 20 feet long that has been mentioned previously. That vessel had an L /D ratio of 4 and it was found that the required thick ness would be 0.414 inch. Suppose that it were decided to use a single stiffening ring in the middle of the vessel with the idea that the thickness of the shell might be decreased. If such construction were used, the L /D ratio would be 2, the t/D ratio would be 0.00525, and the required thickness of the shell would be 0.315 inch. For this construction, the L, or the length between the head and the ring, would be 10 feet, or 120 inches. The working pressure is 15 pounds so that the product of these two is 1800. Locating this value on the chart for stiffening rings and following the line horizontally to a diameter of 60 inches, it will be found that a moment of inertia of 2.5 is required. By reference to structural steel tables it can be seen that an angle 3/4 inches by /4 inch thick would be satisfactory if the 3-inch leg were attached to the shell. Of course any other shape having a moment of inertia of 2.5 would he satisfactory. For instance, a rectangular bar of iron 2/4 inches by 2/4 inches would meet the requirement. Instead of one ring two or even more could be used and it would be found that for this particular vessel every increase in the number of rings would result in a thinner plate and a smaller size of stiffening ring. The limit to such construction would be an economical one and con sideration would have to be given to the relative cost of additional rings and the expense of attaching them as compared to the cost of the vessel without rings or with a small number of rings. While the above discussion has been from the stand point of design, the same principles can readily be applied to the determination of the safe working pressure for a given vessel. In making such a determination it is well to first determine to what pressure a vessel would he limited by the size and spacing of the rings attached to it. It" those rings are found adequate for the desired p r e s sure. then the question of whether the shell plate of the vessel is of sufficient thickness mar be investigated. Supporting rings may be either interna! or external. It will lie apparent that when internal rings are used, it is sufficient merely to secure the rings in place so that they will not more. In the case of outside rings it is necessary to provide sufficient rivets or a sufficient amount of welding to adequately secure the rings to the shell. The size and spacing of such rivets and the minimum amount of welding are given in the code. In developing methods for the calculation or design of cylindrical vessels under external pressure, it has been assumed that such vessels are truly cylindrical, and it will readily be appreciated that out-of-roundness of such' vessels decreases their resistance to collapse. O n the other hand, some degree of out-of-roundness must be permitted since it is practically impossible to construct vessel that is truly cylindrical. The decrease in strprf&th by the out-of-roundness that is permitted is tHkfm into consideration in the factor of safety required. The effect of out-of-roundness on decreasing the re sistance of a vessel to collapse depends on both the L/D and t/D ratios and it, therefore, is impossible to give the permissible tolerance as a fraction of the diameter or of tire thickness of the vessel. While formulae have been developed for determination of the permissible tol erance, they are rather complex and, again for simpli fication of the problem, a chart has been made as shown in Fig. 5. (L /D of 4, l/D of 0.0069, and t of 0.414) it will be found from Fig. 5 that an eccentricity of 0.9 times the thickness would be permitted. Since the thickness of shell is 0.414 the permissible -out-of-roundness is 0.372 or approximately inch. The degree of eccentricity is the difference between the maximum and minimum diameters of the vessel and should be measured at several points. In the case of vessels with lap-seam construction, the amount of ec centricity may be the value obtained from the chart plus the plate thickness. Whereas this provision permits a greater degree of eccentricity in vessels of lap construc tion. on the other hand such vessels are permitted only one-half the pressure that would be allowed on a vessel of butt-seam construction. Still another point to which consideration must be given in connection with cylindrical vessels under ex ternal pressure is the manner in which they are sup ported, which should, in all cases, be such that no con centrated loads are imposed on the shell. In the case of horizontal vessels tlicv should be supported at the heads or from the reinforcing rings, if such rings are used. If no supporting rings are provided and if the vessel is of such length that it would sag or be undulv stressed should the only support be at the heads, then intermediate supports should lie provided but these should be in the form of a saddle, the arc of which ex tends over at least one-third of the circumference. On vertical vessels the legs or brackets that might be used should not be attached directly to the shell but to a sub stantial ring which in turn is secured to the shell, thus distributing the load. There are 1792 tubes of \ y 2-inch bore welded into and connecting the two tube plates. The calandria section was subjected to a test pressure of 375 pounds per square inch and the upper shell 285 pounds per square inch. All the main seams were X-rayed, and altogether about 1200 X-ray photographs were taken of the welding of the four vessels. Tw o Boiler Shop Tools Two devices which assist greatly in connection with boiler works at the Denver, Colo., shops of the Chicago, Burlington & Quincy are shown in the illustrations. The first is a power attachment for cutting off and rolling flues in the front end. This device consists of a revers ible air motor with power attachment and worm-gear drive to a 6-foot cutter bar, this bar being mounted on a 3-inch horizontal steel tube suitably supported by brackets bolted to the boiler front ring. A gear box makes two speeds available for use, dependent upon whether large flues or small tubes are being cut. Reference to the illustration shows that the cutter bar is capable of swing ing vertically or sliding horizontally on the 3-inch hori zontal tube. The machine may thus be used for cutting an entire set of flues without resetting the supporting bar and brackets. The cutter bar has a telescoping bar and universal Russia Building Locom otive Flash Boiler By G. P. Blackall It has just been announced from Moscow that the Kolomensk Locomotive Works near that city is shortly to build a new type of flash boiler with condenser, which will consume considerably less fuel than existing locomo tive boilers. The locomotive will be able to travel 7000 miles without having to take water. The new boiler is designed for a pressure of 1400 pounds per square inch. Though only 20 tons heavier than the Russian " IS " locomotive, the new locomotive will be able to develop 4000 horse}>ower, as against the 2500 horse|x)wer of the "IS " locomotive, with a con sumption of 60 percent less fuel. The Kolomensk Works is at present building an experi mental 600-horsepower locomotive of the new design, and, when this has been thoroughly tested, building will start on the 4000-horsepower locomotive. L arge W elded P ressure V essel Four 50-ton evaporators recently made in the United Kingdom for the new sugar refinery of Tate and Lvle, Ltd., at Silvertown, London, are claimed to be the larg est welded pressure vessels ever made to Lloyd's Class 1 code. These vessels, which have been made by G. A. H ar vey and Co.. Ltd., are 26 feet 9 inches high and 11 feet in internal diameter. They are designed for a working pressure of 250 pounds per square inch on the shell. Each consists of two shells, both 10 feet 4 inches high, and a domed top and bottom. The bottom shell, known as the calandria section, is fabricated of U^s-inch plate, and has two tube plates, each in one piece, 1 inch thick. Efficient power attachm ent for cutting off and rolling boiler tubes and flues socket arrangement to accommodate various lengths, de pendent upon the angle of cutter bar adjustment neces sary for any particular tube or flue. Only one knuckle joint is necessary with this arrangement, and in Hew of the rigidity of the drive, very satisfactory' work is p erfo rm ed and a longer life assured for the cutters. The safety factor is also important, as the machine is strongly made and designed so as to present little opportunity for personal injuries. The rubber hose connection to the air motor and conveniently accessible control levers re quired for one-man operation. The device shown in the second illustration is an unusually compact and effective arrangement for counter sinking the rivet holes in flue sheets. This consists of outside diameter and made of steel plate' 1.15 inches thick, electrically welded by the shielded-arc process with equipment supplied by The Lincoln Electric Company, Cleveland. Welded construction of the barrel eliminated a large amount of calking of seams which was necessary with the former method of construction employing riveting. The two longitudinal welds of the barrel were hammer tested at 575 pounds and leak tested at 700 pounds hy drostatic pressure, revealing high quality leak-prooi seams. The welding was done with "Fleetweld 6" electrodes. Easily handled device for counterboring rivet holes in flue sheets a steel frame to which is attached an angle motor for operating the countersink and a small cylinder and airoperated plunger which backs up the countersink and provides the necessary feed. A convenient handle is welded to the frame for greater ease in adjustment of the device and the air line to the cylinder is installed and connected so that when air is applied to operate the motor, pressure in the cylinder pulls the countersink into the rivet hole. The overall length of this device is approxi mately 24 inches. The cylinder has a 4-inch bore and 354inch stroke. The air line is made of 54-inch steel pipe and the air pressure used is that of the shop line, or about 100 pounds per square inch. W elding Used in Odd Fabricating Job This horn-shaped structure, spreading out from 8 inches diameter at the bottom to 8 feet at the top, was once a single flat piece of % 6-inch ingot iron. The structure is still a single piece of metal--only the shape Locom otive Boiler B uilt w ith W ehleil Barrel W'hat is thought to be the first high-pressure boiler ever made with welded barrel and dome, under U-68 (Class 1) rules of the A.S.M.E. Code for fusion welded vessels, was recently completed by Farrar and Trefts, Inc., Buffalo, N. Y. The new boiler is of locomotive type and is for use in oil fields. The barrel is 16 feet 6 inches long. 62(4 inches Welded funnel outlet for sewage disposal is different. It was made by cutting out 26 pieces, then fusing them all together into one integral unit hv the shielded-arc process of electric welding. The struc ture is now being used as an outlet fitting for the cone of a clarifying tank in sewage disposal work. It was fabricated by the Farrel Manufacturing Companv, [oliet, 111. Fabricating, welded locomotive type oil field boiler Atlantic City to Have 1937 Metal Congress The 1937 Metal Congress and Exposition will he held October 18 to 22, in the Atlantic City Auditorium, ac cording to an announcement made recently by \V. H. Eisenman, managing director of this annual metal show and national secretary of the American Society for Met als, after a meeting of the Society's board of trustees in Cleveland. Practical Plate Developm ent-- X IX Layout of a Smokestack Breeebiug A reader has requested that a method of developing the smokestack breeching as illustrated in Fig. 158 be given in connection with the Practical Plate Development series. The smokestack breeching illustrated in Fig. 158 is of the conventional type, with a round top and a wash-boiler section where it joins the boiler. For convenience in lay ing out the breeching, all lines have been taken on the neutral axis of the plate and all joints are assumed to be welded, no allowance being made for lap joints. The breeching to be developed is shown in Fig. 159, the elevation; Fig. 160. the plan, and Fig. 161, the end view. The elevation and plan are readily constructed from the illustration in Fig. 158. The connection be tween the breeching and the boiler in the end view. Fig. 161, must he obtained bv projection from Figs. 159 and 1(H.l. a.- follow.- ; Divide the semicircle E'-B'-F' of the plan. Fig. 160. into am number of equal parts, the greater the number of equal parts taken, the more accurate the final develop ment. In this case ten were taken and the points num bered from 1 to 11 as shown. Then parallel to the center line M -X, draw lines through the points 1 to 11, extend ing same down into the elevation. Fig. 159, cutting the arc K-B and locating the points 1' to 11'. Next draw lines parallel to the center line T-U through the points 1' to IP . Fig. 159, extending these lines into the end view, Fig. 161. In the end view, Fig. 161, on the center line R-S construct the profile, Fig. 162, of the semicircular end of the wash boiler section and divide this section end into the same number of equal parts as was taken in the plan view. Number these points from 1 to 11, corresponding to the same points in the plan view, Fig. 160. Then parallel to the center line R-S, draw a line through the point 1 of the profile, Fig. 162, and extend the line into the end view, cutting the line drawn from tire point 1' of the elevation. The point l" in the end view. Fig. 161, is thus located, and in like manner, draw a line through the point 2 of the profile, Fig. 162, and extend it into the end view cutting the line drawn from the point 2' of the elevation thereby locating the point 2" in the end view, Fig. 161. Continue to use this method and locate the points 3" to 11" of the end view. Connect the points 1" to 11" with a line completing the end view. Fig. 161. In examining the plan view, it will be noticed that the center line M -N divides the breeching into two sym metrical halves and. therefore, a development of one half of the plan view will be all that is necessary; a duplicate of this development will complete the layout of the breeching. Divide the semicircle Fig. 160, into the same number of equal parts as were taken for the semicircular end of the wash-boiler section E '-B'-F' and number these points from a to k as shown. Parallel to the center line M -N . draw lines through the points a to k extending them into the elevation. Fig. 159, cutting the line C-D. Number the intersections from a' to k ', Connect the points a' to k' with the points 1' to 11' in the elevation, U ff G eorge M. D avies lug. 159, by means of dotted and solid lines as shown. These lines will be the surface lines of the object, and in order to develop the pattern further, their true lengths must be found. Divide the arc K-E of the elevation into any number of equal parts, four being taken in this case and numbered from m to E and from F to u as shown. Connect the points m to E and F to u with the jroint H in the elevation. These lines will be the surface^ lines of the triangular sections H-E-G and J-F-K. Next, parallel to the center line M -N, draw lines through the points w to E and ] to u extending same into tlie plan and cutting the lines G'-E' and A Number these intersections on G'-E'. m'-n'-o'-p' and on K'-F', ', t', s'. r as shown. Connect the points m ', o', p'. E' with the point H ' and the points u', t', s', r', F' with the point / ' in the plan, Fig. 160. The next step is to obtain the true length of all the solid and dotted surface lines as drawn on the elevation, Fig. 159. and to accomplish this, it will be necessary to construct a series of right angle triangles. Problem Xa. 15 for Readers to Lay Out PROBLEM No. 15 The correct solution of Problem No. 15 will be published in the February issue ... 339 - . - y* Dfaits of layout for smoke stack breeching Construction of R ight A ngle T riangles In constructing the right angle triangles in order to obtain the true lengths of the solid surface lines of the triangular sections H-E-G and J-F-K of th e elevation, draw any line as x-y, Fig. 163, and at zt erect a perpen dicular to it. From w on the base line, step off the dis tance zv-rn equal to a-m' of the plan and from zv on the perpendicular step off the distance zv-a' equal to a'-m of the elevation. Connect the points a'-m, Fig. 163. This line will be the true length of the surface line a'-m of the elevation, Fig. 159. In like manner, from w on the base line, step off the distance w-n equal to a-n of the plan, Fig. 160, and from w on the perpendicular, step off the distance zu-a' equal to the vertical distance between the point n and the line C-D of the elevation. Connect this po in t a' with point , the line a'-n being the true length of the surface line a'-n of the elevation. Continue in this manner, taking the bases of the triangles zu-o. za-p equal to a-o' and a-p' of the plan and w-r, w-s, zv-t, zi'-u equal to k-u', k-t', k-s', k-r of the plan. This will also make the altitudes zv-a' and zv-k' equal to the vertical dis tances between the points o, p, r, s, t, u and the line C-D of the elevation, completing the solid surface lines of the triangular sections. . . .k ' j r r o ie in n t n 1 4 -- M ir r i5 i j u iiy o u i Cone and Elliptlca] Intersection N Problem No. 14 appeared on page 242 of the September issue. The correct solution is published herewith in order to give our readers who have developed the problem an opportunity to check their work The true lengths of the solid surface lines of the semi circular ends must be obtained next. Draw any line as xx-yy, Fig. 164, and at ww erect a perpendicular to it. From ww on the base line, step off the distance ww-6' equal to /-6 of the plan, Fig. 160, and from ww on the perpendicular, step off the distance w w -f equal to the \vertical distance between the point 6' and the line C-D of the elevation, Fig. 159. Connect the points 6 Fig. 164, with a line, which will be the true length of the solid surface line /'-6' of the elevation, Fig. 159. Continue in same manner, making the bases of the triangles equal to the distances e-5, d 4, c-3, b-2, o-l, g-7, h-8, t-9, ;-10, -11 of the plan and the altitudes of the triangles equal to the vertical distance between the line C-D and the points 5', 4', 3', 2', 1', 7', 8', 9', 10', 11', respectively. Then connect the points as shown in Fig. 164, completing the right angle triangles for the solid surface lines. The true lengths of the dotted surface lines are ob tained in the same manner and are shown in Fig. 165. The bases of the right angle triangles are made equal to /-5, e-4, d-3, c-2, b-1, f-7, g-8, /t-9, *-10, /-11 of the plan, Fig. 160, and their respective altitudes are made equal to the vertical distance between the line C-D and the points 5', 4', 3', 2', 1', T , 8', 9', 10', 11', of the elevation, Fig. 159. Connect the points f - 5', e'A', d'-3', c'-2', fc'-l', f-7', h'-Q', '-10', /'-11' with dotted lines and these lines will be the true lengths of their corresponding dotted surface lines in the elevation. D evelopm ent of O pe n in g in Boiler Draw any line as X -Y , Fig. 166, and at O' erect a perpendicular to it. O n the peipendicular, step off 0 '-C Q and 0 '-K equal to O-G' and O-K' of the plan view, Fig. 160. Through G and K draw lines parallel to X -Y . On these lines, step off G-E equal to G'-E' and K c-F equal to K'-F' of the plan view, Fig, 160. Draw the line E-F , Fig. 166, and from E-F on the line X -Y step off the distances l'-2', 2'-3', 3'-4', 4'-5', 5'-6' equal to the distances l'-2', 2'-3', 3'-4', 4'-5', 5'-6' in the elevation, Fig. 159. Then parallel to E-F, draw lines through the points 1', 2', 3', 4', 5', and 6', extending them on both sides of the line X -Y . At the point Z on X -F, draw the profile, Fig. 167, of the semicircular end of the wash-boiler section and divide it into the same number of parts as was taken in the plan view, Fig. 160. Number these points from 1 to 11, corresponding to the same points in the plan. Then through the points 1 and 11, Fig. 167, draw lines parallel to the center line X - Y , extending same into Fig. 166 and cutting the line drawn through point 1', Fig. 166, thereby locating the points 1 and 11. In the same manner, through the points 2 and 10, Fig. 167, draw lines parallel to the center line X -Y and extend these lines into Fig. 166 cutting the line drawn through the point 2' and locating the points 2 and 10, Fig. 166. Similarly, locate the points 3 and 9, 4 and 8 , 5 and 7, and 6 . Connect the points C T 0 to 6 to 11 to K with a line, which will complete the development of the opening in the boiler. D evelopment of th e P attern Draw any line as in Fig. 168 and on it step off the distance /-6 equal to 6', Fig. 164. With 6 as a cen ter and with the dividers set equal to 6 -7, Fig. 166, scribe an arc. Then with f as a center and with the 342 Boiler Maker *nd Plate Fabricator trams set equal to f-7 ', Fig. 165, scribe a second arc, cutting the arc just drawn and locating the point 7, Fig. 168. With / as a center and with dividers set equal to f-g, Fig. 160, scribe an arc, then with 7 as a center and with the trams set equal to 7'-g', Fig. 164, scribe an other arc, cutting the arc just drawn and locating the point g, Fig. 168. Continue in this manner, making 7-8, 8-9, 9-l0, 10-11 equal to their corresponding dis tances in Fig. 166 and making 7-8 , h-9, -10, / - l l 0 equal to g'-8', K-9', i'-10\ ; '- l l', Fig. 165, and 8-A, 9-*; 10-/, 11 -k equal to 8'-K, 9 1 0 ' - / ' , 11'-*', Fig. 164, and g-h, h-i, i-j, j-k equal to g-h, h-i, i-j and j-k, Fig. 160, completing the pattern to the line -11. With 11 as a center and with the dividers set equal to ll'- r, Fig. 159, scribe an arc, and with k as a center and with the trams set equal to k'-r, Fig. 163, scribe an arc, cutting the arc just drawn, locating the point r , Fig. 168. Continue in the same manner, making r'-s', s'-t', t'-u' equal to r-s, s-t, t-u, Fig. 159, and k-s\ k-t', k-u equal to k'-s, k'-t, k'~u, Fig. 164, completing the pattern to the line k-u'. From the line c - f develop the opposite side of the pattern in the same manner, completing the half pattern of the breeching. A duplicate of this pattern will comr plete the full pattern of the breeching as shown in Fig. 158. right-side wall was blown out entirely, leaving no sup port under that side of the boiler, as the boilers were set on brickwork instead of being supported from the beams. This caused an excessive strain on the main steam pipe which held the boiler in place. Fortunately, there was no water in the boiler at the time, for that added weight would probably have caused the piping to break and the boiler to fall. The Locomotive. Continuous Dual Are Control W elder A new line of single operator arc welders has recently been made available by The Lincoln Electric Company, Cleveland. These new welders will be known as the " Shield Arc SAE" and will supersede the present tvpe of " Shield Arc" which have been on the market for the last six years. The predominating feature of this new' arc welder is a new method of arc control which makes Baldw in-Southw ark D evelop W eld Tester A new hydraulic machine for accurately testing the strength of spot welds has been developed and built by the Baldwin-Southwark Corporation, Philadelphia, for the Edward G. Budd Manufacturing Company. This 10,000-pound tension testing machine is supplied with a round base for rolling from place to place and a hoist ing hook for moving with a crane. It is a completely self-contained unit having an overall height of 70 inches, an 18-inch diameter steel base, a low center of gravity, and weight of approximately 800 pounds. An 8-inch precision dial indicates the load. Fluid under pressure is pumped by a gear pump situated in the base of the machine. This pump is direct-connected to a* J4-horsepower motor. A specially designed type of self-alining, lexer-operated, renewable file-face grips is used. These grips are so designed that hard, sharp faces can be quickly installed at a very low cost, being made of short sections of machine cut files. The upper grip is of the open face type, while the lower grip is of the closed type with wide angle entrance. These grips will accommodate offsets in welded specimens from the smallest gage to kj-mch thick without using back ing plates or liners. Specimens up to 1J4 inches wide can be tested. Valve Leaks Cause Boiler Explosion A leaky stop valve on the pilot light and a leaky plug cock on the main burners of a gas-fired power boiler-- Xo. 2 of a pair in a California plant--caused a furnace explosion which did $2500 damage to the boiler setting. The escaping gas, which had filled the furnace and flues of the idle boiler, was ignited through cracks in the center brick wall between the two boilers five min utes after the No. 1 burner had been lit. The rear wall was bulged and pushed back about nine inches. The New continuous S A E dual control arc-welder possible the adjustment of both arc heat and arc pene tration in a continuous sequence of fine increments. It is claimed this continuous dual control assures absolute uniformity of performance at every control setting and adds greatly to the successful operation of arc welding. These claims are based on the operation of a large num ber of this type welder which have been in actual serv ice in customers' plants for the last year. It is a well-known fact that for certain types of arc welding a low voltage with wide range of current con trol is desired. For other types of work a higher vol tage wdth the same wide range of current is highly de sired. The new welder therefore permits the use of the correct voltage and current for all classes of work in the range of each size of machine. P.R.R. Research Activities How the Pennsylvania, through research and experi mentation. utilizes the advances of science, new inven tions and improved technical processes for the improve ment of its freight and passenger service is told in a special report which ho Twn*-l> : Com m ittee Reports on Dust Control The report of the preventive engineering committee of the Air Hygiene Foundation, written by Professor Philip Drinker of Harvard, chairman, and other technical spe cialists on the committee, advises that engineers in the "dusty trades" can and should cut heavy dust concentra tions below the present limits warranted by medical knowledge. This action is important, the report explains, not only to further safeguard the health of workmen but to give employers the maximum protection against un just claims. Concerning the size of dust particles, the report ol serves that much lias been made of the fact that particles found in autopsied lungs are of the order of 1 micron ( Vi.10oo of an inch)--about like the common bacteria. It is argued, therefore, that the human anatomy and physiology exercises "some phenomenally accurate size grading which excludes larger particles." The rejiort says "there is no reason whatever to look for any such mysterious explanation. The sizing is done in the air before the dust is breathed and not by the man after it has been breathed." It i> pointed out that the larger particles tend t<> fall fro m the air by their own weight and that "only those small enough to act as part of the transporting air stream are likely ever to reach the lungs." "In diseases such as silicosis and asbestosis, particles must reach the alveoli (minute air sacs of the lungs) or no silicosis or asbestosis results. In maladies like hay fever, the harm is done by particles which may be 15-30 microns instead of 1 micron. "Toxic dusts such as lead and manganese are much more likely to produce ill effects if breathed than if swal lowed. The reason for this difference is physiological; it is established and should not be ignored in dust con trol problems. Again, common-sense tells us that the finer particles of lead are vastly more apt to be breathed than the larger. " It follows then that dust control for hygienic reasons should be aimed at the fine rather than the coarse parti cles. Continuing this argument to its logical conclusion, if one could avoid use of 1 micron dusts or less, or ex clude them from the dust which passes a 325-mesh screen, nearly all dust diseases would be eliminated. This is not at all an academic idea, for de-dusting processes are not new and are being applied in many industries. If some of the mechanical ingenuity which is now being applied unthinkingly to creating 1 micron dust were directed to wavs for avoiding it. probably it would be discovered that dusts which are too large to he breathed would serve many processes just as well as those which are around 1 micron in size." The report includes a tabic giving latest available in formation on the minimum air velocities necessary in certain industries to insure the maintenance of dust con centrations at safe levels. The preventive engineering committee asserts that many firms have neglected heavy dust concentrations in cases where the dust is of no p ro v en harm , and adds : "There is no satisfactory medical answer at present to this question, but the engineer is making a had mistake if he lets men breathe heavy dust concentrations of any material. If no other reason for dust control can he found, then one should read transcripts of some of the recent suits at common law in which fantastic damages for alleged silicosis were granted to men who breathed dust containing little o r no silica. The courts and cornpensation boards are not impressed with subtle distinc tions between dusts with 10 percent and 40 percent quartz, especially when medical experts are reluctant to make definite statements as to the comparative signifi cance of such differences. " It would be well to realize that men working in dustv trades suffer far more from respiratory troubles of ail kinds than do men who work in clean air. The evidence that excessive dustiness of any kind is harmful is beyond argument." The committee attributes the handicap in this general field to the lack of fundamental data and recommends a number of specific engineering researches for the Foun dation to undertake in the coming year. Republic Appoints Special Representative William Hogenson has been named special representa tive on Toucan Iron enameling stock, according to an an nouncement by F. H. Raniage. manager of sales promo tion. Republic Steel Corporation. His work will be in conjunction with that department under the new Product Development Division. Mr. Hogenson comes to Repub lic with a background of technical attd business training gained at the universities of Michigan and Chicago, and a close association with the enameling industrv through his most recent connection. Chicago Vitreous Enamel Products Companv. Engineering Experiments'Bulletins The Engineering Experimental Station of the Uni versity of Illinois has issued recently a series of bulletins dealing with a variety of engineering problems. Bul letin No. 283. written by Frederick G. Straub, deals with "A Study of the Reactions of Various Inorganic and Organic Salts in Preventing Scale in Steam Boilers." Bulletin No. 284, dealing with "Oxidation and Loss of Weight of Clay Bodies during Firing." was written by William R. Morgan. Bulletin No. 285, " Possible Re covery of Coal from Waste at Illinois Mines." was written by Cloyde M. Smith and David R. Mitchell. Bulletin No. 286, by Hardy Cross, discusses and de scribes an "Analysis of Flow in Networks of Conduits or Conductors." Copies of these publications mav be obtained without charge upon application to the Engi neering Experimental Station, Urbana, 111., up to March 1, 1937, or until the supply is exhausted. Byers Appoints New Manager of Sales Promotion M. J. Czamieeki, vice-president in charge of sales, A. M. Byers Company, Pittsburgh, announces the follow ing appointments that were made effective November 2. 1936; George B. Cushing as manager of sales promotion. Mr. Cushing came with A. M. Byers Company in 1928 to organize and head the present advertising department. Subsequently in 1931 he organized a technical promotion group now known as the Engineering Service Depart ment. B. D. Landes, who has been in the technical group since its inception, has been appointed manager of the Engineering Service Department. T. C. Winans. who has been in the advertising depart ment since 1930, has been appointed advertising man ager. Both the manager of the engineering service depart ment and the advertising manager become a part of the B oiler M aker aud Plate Fabricator Re*. U . S. P a t Off. VOLUME XXXVI N U M B ER 12 P UBLISHED Monthly by tho 1309 Nobln Street, Philadelphia, Simmorw-Boardman Publishing Company, Pa., with Editorial and Executive Offices a t 30 C hurch S treet, New York C ity , and IQS W. Adams Street, Chicago, 111. Washington, D. C.: 832 National Press Building. Cleveland: Term inal Tower. Samuel O. D unn, Chairm an of Board, Hitry Lee, President, C. R. Mills, Vioe- Prm ident. Lucius B. Sherm an, Vice-President, Roy V W right, Vice-President and Secretary, F. H. Thom pson. Nico-Preddetii, EL T . Howaon, Vice-PresidentF. C. Koch, Vice-President, John T . D eM ott. Treasurer. Subscription price in United States and possessions, l year, $2.00, 2 years, $3.00; C anada, 2 y ear, $2.00, 2 years, $3.00; foreign countries, 1 year $3.00, 2 years, $5.00. Single copies, 35 cents each. Bequest for change of address should reach us on or before tbc 15th of the month preceding the issue with which it in to go into effect. I t is difficult and often tin* possible, to supply back numbers to replace those undelivered through failure to end advance notice In sending us change of address, please be sure to send use your old address as well as the new oue. Address H. EL McCandlees, circula tion manager, 30 Church Street. New York, N. Y B O ILER M A K E R AND PL A TE FA B R IC A TO R is a m ember of the Associated Business Papers, Inc. (A. B. P-). end the Audit Bureau o f C irculation, (A. B. C.) ED ITO R 1AL S T AFF: H. H. Brown. Editor. L. S. Blodgett, M anaging E ditor. H. W. M acDonald. Associate Editor. BUSINESS MANAGER: W arner Lumbard. been definitely successful, the use of electric welding in the manufacture of heavy machinery can be increased many fold. As a first step therefore, the program will concentrate on the converting of cast parts to welded steel in machinery construction. H. S. Card, formerly editor of the Welding Engineer, has been appointed development director of the weld ing section and will be in charge of the Pittsburgh office. D. L. Mathias Joins Metal and Thermit Corporation as Research Engineer The Metal & Thermit Corporation, 120 Broadway. New York, announces that D. L. Mathias joined its stati on November 2 in the capacity of research engineer. He is the inventor of a number of types of welding elec trodes and processes ; and at the Metal and Thermit Cor poration will be in charge of electrode research and de velopment. Trade Publications Contents Page E D IT O R IA L C O M M E N T ........................................................................................ 323 GENERAL: New H aven Steam R a 'l T rain F eatu res B eder A utom atic B oiler........... 324 M achine-M ade Jobs and Present E m p lo y m en t............................................ 328 Steam otive-- A M odern Power U n it................................................................. 329 M arine Steam Boiler D evelopm ents................................................................. 331 Explosions in Compressed Air L i n e s ............................................................... 331 AU-Welded Smokestack E re c te d ........................................................................ 332 Application o f Code Rules to Vessels Under E xternal P ressu re .............. 333 R*)fsia Building Locomotive Flash B o iler....................................................... 337 Large Wekh d Pressure V essel........................................... ............................ 337 Two Boiler Shop T o o ls........................................................................................ 337 Locomotive Boiler B u ilt w ith W elded B a rre l................................................ 338 W elding Used in Odd F abricating J o b ............................................................. 338 P ractical P lite D evelopm ent--X I X ................................................................ 339 Baldwin-Southw ark Develop Weld T e ste r.........................................................342 Valve Leaks Cause Boiler Explosion .............................................................. 342 C ontinuous D ual Arc C ontrol W eld er................................................................ 312 C om m ittee Reports on D ust C o n tro l..................................... .................. 343 R epublic Appoints Special R ep rese n ta tiv e ...................... ...................... 343 Byers Appoints New M anager of Sales Promotion 313 QUESTIONS AND ANSWERS: Sm okestack B reeching................ Locomotive Boiler Horsejxmer ... Flue Sheet Braces and ShylHj|ls 315 ............... 345 315 A SSO C IA T IO N S.................................. 347 S E L E C T E D P A T E N T S ................................................................................................ 348 newly formed sales promotion group headed by Mr. Cushing. R. H. Gardner, formerly of the Washington, D. C., office of A. M. Byers Company, has been appointed man ager of pipe sales and will take over all sales manage ment duties in connection with wrought iron and steel tubular products. Applications of Welding Studied Realizing the need for co-operative development of the industrial applications of the electric welding proc ess, the electric welding section of the National Elec trical M a n u fa ctu rers' A ssociation has established develop ment headquarters in the Frick Building, Pittsburgh. The welding section has initiated a program of co-opera tive industry development to investigate the electric welding market and determine the possibilities of ex tending it. It has been conservatively estimated that by securing the widest possible adoption of applications which have R iveted P lates.--A pamphlet describing the con struction of a large tunnel shield fabricated by riveting has been issued by the William B. Pollock Companv, steel plate fabricator, Youngstown, O, B last Cl e a n in g .---The Pangborn Corporation. Hag erstown, Md., has issued bulletin No. 201a on the Pangborn type RA-2 Rotoblast cleaning unit. This device is used for the cleaning of castings and forgings of vari ous metallic materials and steel products of innumerable shapes and sizes and operates without the use of con densed air. A irco A cety len e.-- A booklet entitled "Airco Acety lene" has been prepared by the Air Reduction Sales Com pany, New York, and gives a concise presentation of the story of acetylene versus various other fuel gases. A diagram worthy of consideration is included in the honklet and shows the comparative consumption of ow gm by the various fuel gases. boRGiNG P resses.--The Chambersburg Engineering Company, Chambersburg, Pa., has published recently a new catalogue on the Chambersburg " L'nited" high-speed steam-hydraulic forging presses. A complete descrip tion is given of the operation of the various types of presses. Illustrations are shown of installations in vari ous industries and tables of dimensions of the complete line of presses are included. M onel M etal.-- A bulletin entitled " Strength Plus" has been recently published by the International Nickel Company. Inc., New York, that describes the solution to scores of metal problems encountered bv the engineer. This bulletin, profusely illustrated, covers specific prob lems in engineering fields from hydroelectric and steampower plants to highway maintenance, refrigeration and automobiles, in which applications of Monel can lie used successfully. STEAM G e n e r a t in g E q u ip m e n t .-- A new holler c a ta logue, No. 102, of striking design and appearance, has been recently published by the Edge Moor Iron Works. New York, manufacturer of process equipment. Holers and welded steel products. All types of watertube toilers manufactured by the Edge Moor Iron Works are covered in the calalogue and important accessories such as water walls, air preheaters, and waste-heat boilers are briefly discussed. Questions and Answers Pertaining to Boilers This department is maintained for the purpose o f helping those who desire assistance on boner and plate fabricating problems. Inquiries should bear the name and address of the writer. Anony mous communications will not be con sidered. The identity of the writer, however, will not be disclosed unless special permission is given to do so. B y G eorge Hi. D avis Smokestack Breeching In r e y a u ! to the lavoui oi s m u k o t a c k hr eecmngy. cat- the same meihot! >A Invinit he ap pl ied to a smaller s tac k or o u r of le~> t h a n '22 i: cht-' tliameie: with fiat scat> on the Boiler: J . L. T. A.--Tlie development of the breeching submitted with the question is shown in Practical Plate Development Article AIX. The method of developing the breeching would be the same should the diameter of the stack be made less than 22 inches. Problem No. 15 of Practical Plate Develop ment shows such a condition, the solution of which will appear in the January issue. Locomotive Boiler Horsepower Q.---In y our Questions and A nsw ers D epartm ent o f Boiler.M aker ash P late F abricator, I see th a t you give some very interesting and helpful inform ation, and 1 wonder if you would publish the methods used to cal culate th e horsepower of an o rdinary locomotive boiler which carries 200 pounds per square inch steam pressure. M. W. S. A.--The question does not include the proper infor mation for determining the horsepower of a boiler. Boiler horsepower is taken as a measure of evapora tion. One boiler horsepower is equal to the evaporation of 34.5 pounds of water per hour from and at 212 de grees F. For locomotive boilers, it is generally desirable to make the boiler and cylinder horsepower equal. The following rules are based on cylinder and boiler horsepower and on proper evaporating values being as signed to firebox, tube and flue, arch tube and combus tion chamber heating surfaces. Horsepower -- 0.02120 X P X A for saturated steam. Horsepower -- 0.02290 X P X A for superheated steam. W here: P -- boiler pressure, pounds per square inch. A -- area of one cylinder in square inches. Maximum horsepower is assumed to be reached at the follow ing piston speeds: Saturated steam-- 700 feet per minute. Superheated steam--1000 feet per minute. The amount of steam required per hour, per horsepower is taken as follows: Saturated steam = horsepower X 27.0 pounds. Superheated steam r= horsepower X 20.8 pounds. The pounds of steam evaporated per hour per square foot of heating surface are taken as follows: Firelxix heating surface = 55 pounds per hour per square foot heating surface. Combustion chamber heating surface = 55 pounds per hour per square foot heating surface. Firebox watertubes = 55 pounds per hour per square foot heating surface. 2-inch tubes. 18 feet long, t'his-inch spaces = 9.54 pounds per hour per square foot heating surface (base figure). 2J<f->nch tubes, 18 feet long, ^tin-inch spaces = 10.0 pounds per hour per square foot heating surface (base figure). The values for tube heating surfaces vary with the spacing and length of the tubes. Various engineering handbooks give tables of evaporation for tubes and flues for various lengths and spacing. Example : A locomotive with 23-inch bv 28-inch cylinders, using saturated steam at 200 pounds pressure : Horsepower = 0.02120 X P X A. Horsepower = 0.02120 X 200 X 415.48. Horsepower = 1761. Total steam consumption per hour -- 1761 X 27 = 47,547 pounds. Firebox area assumed to be 212 square feet with evaporation at 55 pounds: consumption = 11,660 pounds per hour. 47,547--11,660 = 35,887 pounds steam to be evaporated by tubes. The heating surface area of one 2-inch tube, 20 feet long, after deducting for tube sheets -- 10.423 square feet. Tubes 2 inches diameter, 20 feet long, spaced ^-in ch rate of evaporation = 8.32 pounds per hour per square foot heat ing surface. Evaporation for each tube = 10.423 X 8.32 = 86.7 pounds per hour. Number of tubes required = 35,887 -f- 86.7 = 414. With a given boiler, the problem reverts to obtaining the horsepower based on the actual heating surface of the boiler and comparing it with the cylinder horsepower based on the size of the cylinders and the boiler pressure. The boiler horsepower based on evaporation should be at least equal to 100 percent of the cylinder horsepower. Flue Sheet Braces and Staybolts Q.-- W h at would be the load in pounds per square inch on a front flue sheet brace of 1 3/16-inches diameter, supporting 80 square inches of a boiler 102 inches in diam eter and carrying 220 pounds pressure per square inch. Please show figures in full showing how this is done. Also show' figures in full showing how to find the area of any size of a stayboh at the root of thread or at the reduced section, minus the area o f the telltale hole.-- J . G. M. A.--The question does not include sufficient informa tion on the type of brace used, or the manner in which the brace is connected to the tube sheet to give a com plete answer. Using the information as given in the question, the problem resolves itself into determining the stress on a 13/, (--inch diameter brace rod supporting 80 square inches of a front tube sheet, supporting 220 pounds boiler pressure, and is as follows: The product of the net area in square inches multi plied by the maximum allowable working pressure in pounds per square inch, gives the load to be supported by the brace. Assuming 80 square inches to be the net 346 Boiler Maker and Plate Fabricator area to be supported by the brace, the total load sup ported by the brace would be: 80 X 220 = 17,600 pounds, load supported by brace. The load on the brace in pounds per square inch, usually termed the stress on the brace in jxiunds per square inch, would be the total load on the brace divided bv the net cross-sectional area of the brace. The cross-sectional area of a l :{j 0-inch diameter brace would be: /1.1875 \ * 3.1416 x l -- ------1 -- 1.108 square inches. The stress in pounds per square inch on the brace would Ire: 17.600 -- 1.108 = 13.893 pounds xt square inch. total load or stress on the brace. This load would be in excess of the maximum allow able stress for staybolts and stays or braces as provided for in the A.S.M.E. Power Roiler Code. The code provides as follows: M aximum A llowable S tresses for S taybolts and S tays o* B races Stresses, pounds per square inch _____________ A____________ Description of staybolts and stays or braces For lengths between sup ports not ex ceeding 120 diameters* For lengths between sup ports exceed ing 120 diam eters' a U nwelded or flexible staybolts less than tw enty diam eters1 long, screwed through plates w ith ends riveted o v e r.................... b Hollow steel staybolts less than twenty diam eters1 long, screwed through plates with ends riveted o v e r.................................. c Unwelded stays or braces and unwelded ixjrtions of welded stays or b ra c es........... d Steel through stays or braces exceeding 1Yi inches diameter* .................................... t W elded portions of stays or b ra c es........... 7,500 8. <00 9.500 10.400 6,000 8,500 9.000 6.000 1 Diam eters taken at body of stay or brace Assuming that the stay in question was an unwelded stay, the length of which exceeds 120 diameters, the diameter of the brace, in order to supjiort the load as Standard Thread Fig. 2.--Whitworth Standard Thread Fig. 3.--Sharp V Thread given in the question and still stay within the maximum allowable stress on braces, would be calculated as follows: Determine the required cross-sectional area of the brace, by first computing the total load to !>e carried by the brace, and dividing the total load, by the value of the allowable stress for unwelded braces for lengths between supports exceeding 120 diameters. Total load on brace = 17,600 pounds. Allowable stress on stay = 8500 pounds per square inch. 17,600 -f- 8500 -- 2.07 square inches. Referring to any engineering handbook, we find that a l^ -in c h diameter brace has a cross-sectional area of 2.074 square inches. Thus, to su p p o rt 80 sq u are inches of surface, under a load of 220 pounds jter square inch and stay within the allowable stress of 8500 pounds per square inch, a 15'8-inch diameter brace rod would have to be used. Staybolts. generally, are either threaded with U. S. Standard, Whitworth or Sharp V-threads, with 12 threads per inch. The area at the root of the thread is found by obtaining the diameter at the root of the thread, as follows: First obtain the depth of the thread from the follow ing formulas: U. S. Standard Thread (Fig. 1) 1 P = pitch = --------------------------------- No. threads per inch t -- depth = pitch X 0.6495 pitch / = flat = ------- 8 Whitworth Standard Thread (Fig. 2) 1 p' -- pitch = -- ------------------ r- No. threads per inch r = radius -- pitch X 0.1373 t -- depth = pitch X 0.64033 Sharp V Thread (Fig. 3) 1 p -- pitch = ----------------------- -- No. threads per inch / = depth = p X 0.750 then obtain the diameter at the root of the thread the following formula: D' = D--2t where : D' = diameter at root of threads in inches. D = diameter of staybolt in inches. t -- depth of threads in inches: The area at the root of thread would then be: from Area at root of threads = 77 X in square inches. where : 77 =3.1416. D' = diameter at root of threads in inches. From this area, the cross-sectional area of the tell-tale hole is then taken and the resultant area would be the least cross-sectional area of the staybolt. Assuming for example, a staybolt 1-inch in diameter, 12 1'-threads per inch, with a :,/1(i-inch tell-tale hole, the least cross-sectional area would be: first, obtain pitch of threads, (p) 1 P= -- 12 p = 0.0833 inch then, obtain depths of thread, (t) t = 0.0833 X 0.75 = 0.062475 inch then, obtain diameter of root of thread. IV - 1 -- 2 X 0.062475 D' - 1 -- 0.124950 D' = 0.875 inch. then, obtain area at root of thread as follows : /0.875\ * Area = 3.1416 x l ------ J Area = 0.6013 square inch from this deduct the area of a -inch diameter circle or : 0.6013 -- 0.02761 = 0.57369 square inch area at root of thread with area of the tell-tale hole deducted. The area at the reduced section is obtained by using the diameter of the stavbolt at th reduced section. This diameter should he checked against the diameter at the root of the threads and whichever is the least should be used in obtaining the least cross-sectional area of the staybolt. ficeniber, 86 3*/ Associations Bureau of Locomotive Inspection of the Interstate Commerce Commission Chief Inspector--John M. Hall, Washington, D. C. Assistant Chief Inspector--J. A. Shirley, Washington. Assistant Chief Inspector--J. B. Brown, Washington. Bureau o f Navigation and Steamboat Inspection of the Department of Commerce Director--Joseph B. Weaver, Washington, D. C. American Uniform Boiler Law Society Chairman of the Administrative Council--Charles E. Gorton, 95 Liberty Street, New York. Boiler Code Committee of the American Society of Mechanical Engineers Chairman--D. S. Jacobus, New York. Acting Secretary--M. Jurist, 29 W. 39th Street, New York. National Board of Boiler and Pressure Vessel Inspectors Chairman---William H. Furman, Albany, N. Y. Secretary-Treasurer--C. O. Myers, Commercial Na tional Bank Building, Columbus, Ohio. Yice-Chairman--F. A. Page, San Francisco, Cal. Statistician--L. C. Peal, Nashville, Tenn. International Brotherhood of Boiler Makers, Welders, Iron Ship Builders and Helpers of America International President--J. A. Franklin, Suite 522, Brotherhood Block, Kansas City, Kansas. Assistant International President--J. N. Davis, Suite 522, Brotherhood Block, Kansas City, Kansas. International Secretary-Treasurer--Chas. F. Scott, Suite 506, Brotherhood Block, Kansas City, Kansas. Editor-Manager of Journal--L. A. Freeman, Suite 524, Brotherhood Block, Kansas City, Kansas. International Vice-Presidents--Joseph Reed, 3753 S. E. Madison Street, Portland, Ore.; W. A. Calvin, Room 402, A. F. of L. Building, Washington, D. C .; H arry Nicholas, 6215 S. Benton Blvd., Kansas City, M o.; W. E. Walter, 637 N. 25th Street, East St. Louis, 111.; J. H. Gutridge, 2178 South 79th Street, W. Allis, W is.; W. G. Pendergast, 1814 Eighth Avenue, Brook lyn, N. Y .; W. J. Coyle, 424 Third Avenue, Verdun, Montreal, Quebec, Can.; A. M. Milligan, 262 Trent Avenue, East Kildonan, Man., Can.; J. F. Schmitt, 28 S. Roys Street, Columbus, Ohio; W'illiam Williams, 1615 S. E. 27th Avenue, Portland, Ore. Master Boiler Makers' Association President: M. V. Milton, chief boiler inspector, Ca nadian National Railway. Vice-President: William N. Moore, general boiler foreman, Pere Marquette Railway. Secretary-Treasurer: Albert F. Stiglmeier, general foreman boiler maker. New York Central System, West Albany Shop. Address, 29 Parkwood Street, Albany. N. Y.' Chairman Executive Board: William N. Moore. E x e c u t i v e B o a r d -- T h r e e Years : William N. Moore, general boiler foreman. Pere Marquette Railroad; Carl A. Harper, general boiler inspector, Cleveland, Cin cinnati, Chicago & St. Louis Railroad : E. C. Lhnlanf. supervisor of boilers. Erie Railroad. Executive Board--Two Years: M. Y. Milton, chief Iwiler inspector, Canadian National Railway; Charles J. Kline, locomotive inspector, Interstate Commerce Commission; Sigurd Christopherson, supervisor of boiler inspection and maintenance, New York, New Plaven & Hartford Railroad. Executive Board--One Year: George L. Young, boiler foreman, Reading Company; C. W. Buffington, general master boiler maker, Chesapeake & Ohio Rail road ; A. W. Novak, general boiler inspector, Chicago, Milwaukee, St. Paul & Pacific Railroad. American Boiler Manufacturers' Association President: Starr H. Barnum, The Bigelow Company, New Haven, Conn. Vice-President: W. F. Keenan, Jr., Foster Wheeler Corporation, New York. Secretary-Treasurer: A. C. Baker, 709 Rockefeller Building, Cleveland, O. Executive Committee (Three years) ; A. W. Strong, Jr., The Strong-Scott Manufacturing Company, Min neapolis, Minn. R. J. Bros, William Bros Boiler & Man ufacturing Company, Minneapolis, Minn. E. R. Stone, Westinghouse Electric & Manufacturing Company, East Pittsburgh, Pa. (Two years) : E. E. Knoblock. Union Iron Works, Erie, Pa. A. G. Weigel, Combustion En gineering Corporation, New York. J. F. Dillon, Jr., Struthers-Wells-Titusville Corporation, Warren, Pa. (One year) : F. H. Daniels. Riley Stoker Corporation, Worcester, Mass. M. E. Finck, Murray Iron Works, Burlington, la. A. G. Pratt, Babcock & Wilcox Com pany, New York. (Ex-Officio) : Starr H. Barnum, The Bigelow Company, New Haven, Conn. Walter F. Keenan, Jr., Foster Wheeler Corporation, New York. O ffic e of I ndustrial R ecovery Co m m itt ee, 15 P a r k R o w , N ew Y ork Manager--James D. Andrew. Secretary--H. E. Aldrich. Steel Plate Fabricators Association President -- Merle J. Trees, 37 West Van Buren Street, Chicago, 111. States and Cities That Have Adopted the A.S.M.E. Boiler Code States Arkansas California Delaware Indiana Maine Maryland Michigan Minnesota Missouri New Jersey New York Ohio Oklahoma Oregon Pennsylvania Rhode Island Utah _ Washington Wisconsin District of Columbia Panama Canal Zone Territory of Hawaii C ities Chicago, 111. Los Angeles, Cal. Memphis, Tenn. Detroit, Mich. St. Joseph. Mo. Nashville, Tenn. Erie, Pa. St. Louis, Mo. Omaha, Neb. Evanston. 111. Scranton, Pa. Parkersburg, W. Va. Houston. Tex. Seattle. Wash. Philadelphia, Pa. Kansas City, Mo. Tulsa, Okla. Tampa, Fia. Stales and Cities Accepting Stamp of the National Board of Boiler and Pressure Vessel Inspectors Arkansas California Delaware Indiana Maryland Michigan Chicago, 111. Detroit, Mich. Erie, Pa. Kansas City, Mo. States Minnesota Missouri New Jersey New York Ohio Oklahoma C ities Memphis, Tenn. Nashville, Tenn. Omaha, Neb. Parkersburg, W. Philadelphia, Pa. Oregon Pennsylvania R h o d e Isla n d Utah _ Washington W isconsin St. Louis, Mo. Scranton, P a .. Seattle, W ash.' Tampa, Fla. Selected Patents Compiled by Dwight B. Galt, Patent lawyer, Earle Building, Washington, D. C. Readers de siring copies of patents or any information regarding patents or trade marks should corres pond directly with Mr. Galt. chamber beneath the normal water level of the boiler, means fo r tam in g a supply of w ater in the cham ber, m eans fo r passing th e VtdtiBt from the pipe through the chamber while m aintaining it out of confect 1,868,445. B O IL E R . C H A R L E S W . B RA B B LE , O F BRONXV IL L E . NEW YORK, ASSIGNOR TO AM ERICAN RADIATOR CO M PA N Y , O F N E W YORK, N. Y., A CO RPO R A TIO N O F N EW JE R SE Y . . Claim.-- A boiler com prising a grate, a plurality of sections arranged side by side, certain of said sections each having a depending water member com m unicating therewith and term inating at its lower end above with the w ater therein, a connection from the upper part of said chamber to said steam space, two connections from the lower p art of the chamber to the water space of the boiler, and means for causing a circulation through said w ater connections and chamber. Ten claims. 1,918,420. A R C H F O R B O IL E R F1P F .B 0X ?:S . R O B E R T J. N E E D HAM, OF TORONTO, ONTARIO, CANADA. Claim.-- In a locomotive boiler firebox, a baffle arch stru ctu re dividing the firelx>x into a combustion cham ber and a furnace cham ber and com prising a series of w ater tubes having spaced parallel brick-supporting reaches and reaches laterally converged and d is u se d in superposed jvoti- tions to provide increased com m unicating space betw een said combustion chamber and furnace cham ber; and bricks supported by said parallel reaches of the tubes and closing the spaces therebetween. Eleven claims. the prate, each of said members having a transverse opening, said de pending w ater members being arranged side by side and cooperating to form a depending baffle extending transversely of the norm al plane of said sections and dividing the space above the grate into tw o chambers arranged one to the rear of the other, said transverse openings alining com m unicatively to form a duct extending through said baffle, and means a t tfae low er portion o f said baffle for d isch arg in g a com bustion su p p o rtin g gas from said duct. Thirty-tw p claims. 1,917.617. S T E A M B O IL E R . ANGELES, CA LIFORN IA . H EN RY A. U LRICH , O F EO S Claim.-- A steam boiler com prising a casing, a fire box in said casing, means for heating the Ere box, a pair of parallel steam drum s arranged in the casing directly above the fire box, lower drum s arranged in the casing adjacent the fire box, downwardly and outwardly extending banks of tubes connecting the steam drum s to the lower drum s, diagonally ex tending and inter-crossing banks of tubes connecting the lower drum s to 1,864,737. M E R C U R Y C O N D E N SE R W A TER T U B E ST EA M BOILER. W ILLIA M A. JO N ES, OF W ESTERLE1GH, NEW YORK, A S S IG N O R T O T H E BA BCO CK & W IL C O X C O M PA N Y , O F BA Y ONNE, NEW JERSEY , A CORPORATION O F NEW JERSEY. Claim.-- A w ater tu b e boiler com prising tubes and headers, an a ir tig h t casing around said tubes attached to said headers, supports to prevent said casing from moving tow ard said tubes, and means closing the spaces between said headers which together with said headers constitute tne ends of said casing. Ten claims. 1,890,245. S T E A M T E M P E R A T U R E R E G U L A T O R . J O H N E , BLA CK , O F RUM SON, NEW JERSEY , ASSIGNOR TO T H E BAB COCK & W ILCOX COMPANY. O F BAYONNE, NEW JER SEY , A CORPORATION O F N EW JER SEY . continuation, V boiler having a'^eam .space, V superheated gte&m pipe, * temperature regulator connected said pipe and having a tbe steam drum s and arranged directly in the path of combustion from the fire box, deflectors arranged between the first and second banks of tubes, deflectors arranged between the first mentioned deflectors and the walls of the casing for forming downwardly and upwardly extending pas sages with tbe first mentioned banks of tubes arranged in the downwardly extending passages, means connecting the upw ardly extending passage to a smoke stack, feed water heating means in the upwardly extending passages and connected to the steam drum s, a steam collecting drum a r ranged in the casing between the steam drum s, a series of tubes connected to the steam drum s throughout' the lengths thereof and to the steam cob lecting drum , a superheated steam outlet header arranged below th e steam collecting drum , and superheated tubes connecting the steam collecting drum with the super-heated steam outlet header and extending downwardly through the beyond m enuohed banks of tubes. O ne claim* *pX) , C. '$'f!!%xff:r*s?&n*mii Tvyo Pi ece Assemblage BRIDGEVILLE, This Com bination W ill H e lp You M aintain Sch edules A n d Reduce Costs A LLrailway reports indicate that the boiler shops are going to be kept very busy for some time to come. Complete installations of the Two-Piece Assemblage com bined with the use of the Electrical Tester will eliminate many problems, speed up repairs and assure big savings in main tenance costs. The Two-Piece Assemblage will provide a higher factor of safety, eliminate the cause for most broken bolts and reduce stock inventories. The Electrical Tester assures an unfailing method of inspec tion-- reduces inspection costs by 80 per cent and inspection time at least 60 per cent. A ction Now W ill Prevent A Lot of Trouble Next Year. BOLT COMPANY \ PENNA. P A G E Welding 1W IR E GET TOGETHER DEPARTMENT POSITIONS OPEN POSITIONS WANTED POSITION OPEN For Foreman for Boiler Shop. Experienced on weld ed and riveted plate work and laying out. Capable of handling men. Plant in the Metropolitan District. State age, salary required, previous experience, where last employed. Address Box 592, B o iler M a k e r & P l a t e F a b r ic a to r , 30 Church St., New York, X. Y. POSITION WANTED Layerout--20 years' experience in light and heavy plate work of every description. Able to estimate jobs. Ad dress Box 593, B o il e r M a k e r a n d P l a t e F a b r ic a t o r , 30 Church Street. New York. X. Y. Classified Advertisements-- H elp and Situation Wanted advertisements appear ing in the "Get Together Department," 10c a word an insertion. M inim um charge $2.00 for each insertion. For Sale Advertisements $10.00 a column inch. Any number of inches may be used. Copy must be in this office by the 10th of each month preceding to insure insertion in the issue. Locomotive and B oiler Inspector Handbook By A. j. O'Neil Formerly Locom otive Inspector, Transit Com mission for the State of N ew York Furnishes all the information necessary for the boiler maker, machinist, engineer or fireman who wishes to pass an examination for the position of locomotive or boiler inspector. One hundred and sixty-two questions are given which might well form the basis of an examination for inspectors. All Federal laws, rules and requirements of the Interstate Commerce Commission are included. Second edition, 297 pages, 140 illustrations, 5 x 8 inches, flexible binding. $2.50 Sent on Ten D ays' Free Examination Book Service Department Simmons-Boardman Publishing Corporation 30 Church Street, New York, N. Y. *W FLANGED ""DISHED HEADS Flanged and Dished Heads of all types, in large diameters and heavy gauges . . . in Standard, A .S .M .E ., elliptical and shallow dish specifications . . . are W O R T H specialties-- of W O R T H Q U A L IT Y , through and through. Complete mechanical equipment, expert workmen of long experience under intelligent, capable management, and unequaled shipping facilities, guarantee the finest possible work plus the best possible service. Specify W O R T H on your next order-- and be convinced! L iterature an d prices upon request. REPRESEN TA TIV ES* New York, N . Y . Wie. C . Dickey Pittsburgh, Pa. M cK ee-O liver, Inc. 8ostoe, Maas. Edward H . L<oyd Houston, Texas The Corbett Corp. Los AeeaU s, Cafif. Ducoau M etals and Supply C o. S t Loeh, Mo. H u b b c iJ ft Sharp QeveUed, O h io E. f. Bond Detroit, M ich. H . L. Sevin Chicago, HI. Theo. L. Dodd ft C o . Seattle, Wash. W . C . Scott, Jr. Sea Francisco, Calif. W . S. Hanford M oabcat ft T n w ln . C in ifti Drummorrd, M cC a ll ft C o ., Ltd. WORTH STEEL COMPANY CLAYMONT: D - P i ' . s .M & t i - fe -t: y>. mm >.I'&S^SWg*"`vHWt?' . r ,, .i ^ ^ | fR IC A T O H , -r J /4 ^ i .HIS man knows boiler.tubes.; For thirty years he's been builcl-^ ing boilers. Hundreds of tubes haye. passed through his skillful hands. He's watched them go in -- ahd he's seen them, when they came out,. He knows just about what to expect: from a tube the first time he puts a tool to it. Listen to what he says about N a t io n a l Seamless Tubes: " They go in without trouble. " ThirV because NATIONAL Seamless B oiler Tube* / are straight, true to gauge, smooth, clean and round. Exacting mill toleranoe* in s u te ! their dim ensional accuracy. They slide through the tube sheet more easily. Ea^h one is exactly like the other. " They're fa st and easy to install. " NATIONAL Seamless Boiler Tubes can be easily flared, rolled and headed into flue sheets because they are exceptionally duc tile, and because every tube is completely annealed. That means last installation and low labor cost for you. ' "I've never seen one split yet. " N o, and he never will, for the very good reason that NATIONAL Boiler Tubes are seamless --pierced from a solid billet of steel--with- ' out welda that might split or fail during installation o r when the service geta tough. " They last longer." W hy? Because they're made only of " killed" open-hearth or electric furnace steela--of higher creep strength, uniform density and so undnessfree from laminations--w ith improved heat transfer characteristics. A sk for complete descriptive data. N -f* N A T I O N A L T U B E C O M P A N Y P / T T S B RG H , P A . J -r -~V- ' > ; Columbia. Steel Company, 9*o b ra n d a co , Pacific Coast fristrikutorg U nited States Steel Product Q prapafjr, Near T o r f * Hstributma -