The Iron Age 1927-02-10: Vol 119 Iss 6

ESTABLISHED 1855 THE IRON AGE New York, February 10, 1927 VOL. 119, No. 6 Sand System Yields Economies Results in 40 Per Cent Saving in Floor Space ONSERVATION of floor space, a reduction of la- ¢ bor costs and a substantial saving in the amount of new sand purchased each year, have been made possible in the Lima, Ohio, plant of the Ohio Steel foundry Co. by the successful operation of a sand-re- laiming system. All handling of sand by hand has een eliminated and, aside from one minor operation, rane service in relation to sand handling has been made unnecessary. Two separate and distinct systems for reclaiming ind have been developed—one at the south end of the ent editor THe Iron Ace, Cincinnati. Sand Screen a "Reciprocating Conveyors 5 |S Magnetic Pulley 24 Aerating Belt id ny | fa a 7»... Plain Jarring Shakeout Ing Machines Comveyor _42172"Herman RO. . “ Molding Machine 1 42t/a8 Osborne RO. ' _ Molding Machines <° 675Tog Sand Stepage Tanks”. , he Illustration at the Top of the Page Shows a Sand Distributi ¢ of the Foundry at a Height of 70 Ft. In the plan view, of wo systems, one at the south end and the other at the north end of the building New Sand Requirements Cut Down, Labor Eliminated BY BURNHAM FINNEY* foundry and the other at the north end. At the south end, heats are shaken out on a shakeout floor, 50 x 60 ft. in area. The used sand is then put through a cut- ting process in which a grab bucket and overhead crane are utilized. After the sand is tempered by the addi- tion of water and has attained a consistency suitable for molding, it is picked up by the grab bucket and placed on grates over a reciprocating drag adjacent to the shakeout floor. At that point all pieces of metal, such as broken gates and gaggers, are removed. The reciprocating drag carries the sand to an in- clined belt, 24 in. wide and 65 ft. long. The sand is drawn up the belt to a magnetic pulley at the top, Molding Machine Machine i df f 24 Overhead 85-Ton Sand Belt That Extends 450 Ft. Along One nt are shown the two sand reclamation ot eae . ali “to Suieiiaballe re ioe wraes one il Bo tas a i eal = a svame hn uaiatatie TS + Paes eS a ee ee — Laer ane hinemeemeine — an 414 THE IRON AGE February 10, 1997 Reclamation Equipment Includes Conveyors, Magnetic Separator, Screen, Storage Tanks. Blender and Discharge Chutes Hung Directly Over Molding Machines { Sand Handled in the System Pro- vided for the South End 2 | the Foun- dry Passes Through a Sand Blender (at Right) Before It Is Discharged the Distribution Belt That Serves the Molding Machines Sand Is Drawn Off the Distribution Be t Through Chutes Located (ver Volding Machines. Sand is released required from the chutes, one of which is shown below An Inclined Belt, 65 Ft. Long (in Circle at Left) Carries the Sand to a Magnetic Pulley and a Revolving Screen. After screening, the sand goes either to storage tanks or directly to the sand blender Sand to Be Stored Is Deflected through a Discharge Pipe to a Belt (Shown Be- low) Serving Three 85-Ton Storage Tanks. Plows, hung over the belt, divert the sand into the mouths of the tanks Februa! 10, 1927 THE IRON AGE In the North End of the Plant a Pneumatic Shakeout Machine Is Used to Shake Out Molds eparates all iron from the sand. Nails go down tank to railroad cars on a siding just outside the build- to a bench, where they are rattled and straight- ing. further service. Live sand, either from the storage tanks or directly tly beneath the magnetic pulley is a revolving from the bucket elevator, is passed through a continu- which removes foreign matter, such as cinders, ously functioning sand-blending machine, and thence sand goes through it. The screened sand drops to a distributing belt, running 450 ft. along the west- belt, 12 ft. long, which delivers it to a bucket ern side of the foundry at a height of approximately fe tor. The sand is then carried to the top of the 70 ft. The belt supplies sand through chutes to four oe be Se lding, 70 ft. above the floor. If the molding ma- Herman pneumatic roll-over machines. When any of | 1S n the foundry are idle, the sand is diverted to a the chutes are not in use, they are hung on hinges be- t belt, from which it is dropped into storage tanks side the belt so that they will not interfere with the extreme southwestern end of the plant. Each passage of sand along the belt to other chutes. has a capacity of 85 tons. Two are used for “live” At the north end of the foundry is a bolster and , while sand in excess of the amount needed in the side-frame molding department. The sand-reclaiming iry is stored in the third. From time to time the system here differs in many respects from that at the sand is delivered by belt conveyor from the south end. Molds are taken directly to a pneumatic — - sy Ee erated Storage Tanks Serving the System at the North End of the Foundry Are Shown in the Back- From the bins the sand is fed through an agitating cone to a revolving disk, which delivers it to ator serving the two chutes shown in front. The chutes hang directly over two molding floors i 416 af THE IRON a | shakeout machine, of the company’s own design, lo- cated at the edge of the molding floors directly over a 7 reciprocating drag. Shaken into the reciprocating drag, the sand is transported to an inclined belt, 20 ft. in length. at the bottom of which water is added. Upon My reaching the top, it drops into another reciprocating Yi] which delivers it to a second belt, about 12 ft. It then passes over a magnetic pulley, which ves all of the iron, and drops into a revolving ree which eliminates foreign matter. After being reoned the sand is elevated 60 ft. to a third belt, vyhich drops it into storage bins. » storage bins it is fed through an agitating 14 ft. in diameter, which de- lving disk LUBRICATING SYSTEM Positive, Measured Action from Centrally Con- trolled Point in Industrial Units \ cl lubricating system designed for posi- brication with solidified transmission oil from a controlled point has been developed by the Farm Lubrication Systems, Inc., 2611 Sixteenth Street, Detroit. The system, devised originally for use I r cars, has now been applied to uses in indus- r I t ! bricating bearings of line shafting, machine tools, conveyors and other machinery. A De- Through Oil Reservoir (at T vith Strainer) and Compres- Chamber (Horizontal, Below). r) | line to points requiring lu- tion is attached at A. The alve in base of reservoir pre- ents back flow of oil it troit plant has installed the system for lubricating an i i ensive system of conveyors. 'he system consists of four main parts: a pressed ' ia steel reservoir holding a supply of heavy oil, a screw or plunger type of compressor which exerts pressure as required, a valve automatic and positive in action connecting with each bearing through which the oil is forced, and which measures the correct amount of oil to be supplied to the bearing, and a pressure gage —— Te pousnepasteu: ie eR: ne AGE February 10, 1997 livers it to an elevator. From the elevato; ; it passes into chutes located directly over the two m : olding ma- chines. The weight of the sand in the chutes controls an electrically operated mechanism that starts and stops the revolving disk so that on! required amount of sand is fed into the chutes. It is estimated that the reclamation of sanq jy means of the processes described, especially throug) y the the use of the distributing belt at the top of f the build. ing, has cut down the necessary floor space in the foundry 40 to 50 per cent. While figures showing the actual percentage of new sand saved are not t available. the amount is of liberal proportions. mounted near the operating point, which indicates th; amount of pressure in the line. Made in various sizes, depending upon the size , the installation, the reservoir for use with single ma- chines will hold enough oil to lubricate 30 to 40 bear. ings for three months. Oil passes through the reser. voir bottom through a ball check valve into a compres. sion chamber, from which it is forced into a feed ling The ball check valve prevents oil from being forced back into the reservoir when pressure is applied in the compression chamber. A screw type of compressor usually is specified for industrial applications. This is operated by hand wheels, except in large systems re quiring several hundred feet of piping and supplying a large number of bearings. Im these larger systems compression is effected by motor-driven gears. The measuring valve connected with each bearing functions when pressure is applied in the compression chamber. When the lubricant is not under pressure the piston is seated against a copper gasket, shutting off the main supply line. As pressure is applied the oil forces the piston forward and the oil by-passes into the measuring chamber of the valve. When the pressure in the valve equals that in the line the piston again moves forward, forcing the measured quantity of into the bearing. After the piston has traveled its full Assembly of Oil-Measuring Valve, One 0! Which Is Connected with Each Bearing to Be Lubricated length it seats, shutting off the entrance of any more oil into the bearing. When pressure is released ® spring forces the piston back to its original position an° the system is ready for the next application of the lubricant. ee When using valve bodies and pistons of unilor size, the amount of lubricant to be delivered to te bearing is regulated by making the valve seats warns distances from the piston heads, thus regulating distance that the piston travels. The valves are ™" in various sizes to meet the requirements. re Advantages claimed for the system include pr lubrication for each bearing at any required pre™ quick operation, reduction of the labor cost of ee and the elimination of the danger of accidents in 0! bearings that are difficult to reach. ‘ 95. ac Production of tin cans and packages In Saad values cording to reports to the Bureau of Census, was Y°" at $235,736,120. Milk and ice cream cans were ® duced to the value of $5,784,199 and other products from plants engaged in the production of tinware © valued at $18,839,642. This represents a total of ware’ 359,961, an increase of 20.6 per cent, as compared — $215,971,256 for 1923, the last preceding census Y°* About Buying Drop Forgings Where the Dies Belong, and Why—Upkeep and Replacement Expense—Cost of ing reservation, “Charges made for dies and tools do not convey ownership nor the right to remove m from our possession, but they do convey the right their exclusive use.” We are oftentimes asked why make such a reservation. This condition may at first seem to the buyer of ial forgings as an attempt on the part of the forg- r company to create for itself a monopoly, thereby allowing it to charge the customer on subsequent or- ders almost any price it sees fit. If this were the purpose of such a reservation, and if the forging company followed that plan, in a short time that fact would be apparent to the purchaser. Although he might continue to order repeat lots at an unreasonable price, still he surely would never order from that company any more new pieces requiring new dies. Hence the forging company would eventually find itself in a position where it had no new work, and, as the old pieces gradually became obsolete, the forg- ing company would have no business at all. Because the forging company is sensitive to the fact that this reservation may appear to the buyer in this way, it is careful that the actual facts shall clear it of any suspicion of attempting to obtain an un- reasonably high price on forgings. This condition or a similar one is used by most drop forging companies, and it is used to avoid the evils which would exist if it were not used. T quoting on special forgings we make the follow- Dies Would Not Fit Hammers Suppose that no such condition existed anywhere. In that case the purchaser would place his initial order for forgings with that concern which quoted the lowest total number of dollars on the combined forgings and dies. The second time he required the same piece he would place his order with that concern that quoted the lowest price on the forgings only, and would have the dies shipped to that concern. First of the difficulties encountered would be the fact that the dies probably would not fit the hammers of the second forging company. This is because there is no standard in the forging industry for the shape of the shanks of the dies, or, in other words, the shape of the portion of the die which is used to hold it in the hammer. If the shanks on the dies were soft they could be reshanked to a smaller size, but not to a larger one without planing off the entire shank and making a new one, which treatment the die would stand as long as there was sufficent metal. (Adapters to ac- commodate a small shank die to a larger shank ham- mer are not particularly successful.) If the shanks of the dies were hardened it would be necessary to anneal the dies, and then reshank, the same as if they had been soft, and then reharden. There is always risk of breakage in heat treating, and an especial risk in reheat-treating dies. The second forging company would undertake that work only at the risk of the owner of the dies, which in this case would be the customer. Dies Not Standard with Second User _ The next difficulty encountered would be that the ‘les were not designed and made according to the way the second forging company would make them. Each forging company has its own way of designing and making dies, and, although they all may be good, *Kilborn & Bishop Co., New Haven, Conn. Rejections Heavy BY H. KILBORN* 417 nevertheless each one prefers the which has apparently given the best results in its own style or method practice. The second forging company then could hon- estly claim that the design of the dies was such that the rate of production would be less than that esti- mated, and therefore the price would have to be raised. To illustrate this, suppose the first forging company regularly made the edger on the right, the blanking impression on the left, the finishing impression in the center and the cut-off on the extreme left rear corner. All the men in the first company would be accustomed to these positions on all dies and therefore reach their greatest rate of production on that layout. If the second company’s layout were different and its men were accustomed to a different arrangement, although it would be quite true that the dies would produce the forgings, nevertheless the rate of production would be lower for the second company, because the layout was not standard for it. Running the Dies to Death Next and probably the most expensive difficulty is that all forging companies would be using sets of dies which they did not own, and in the upkeep or replace- ment expense of which they had no interest. The ma- jority of purchasers of drop forgings do not realize that the hammer operator has considerable to do with the life of forging dies. A little more care on the part of the operator will greatly increase the life, whereas strict attention to rate of production only, may ruin a set of dies very quickly. Some operators are particu- larly poor in this respect and it is not uncommon to hear an operator described as “Fast, but hard on dies.” It would be natural for the second forging company to attempt to produce the forgings in the least time and without attention to the life of the dies. And, as it would be necessary for the customer himself to pur- chase subsequent sets of dies, and as the life would be less than if the forging company had to stand that expense, the expense to the customer would be greater. These three difficulties have caused drop forging companies, as a whole, to make reservations in regard to dies. But the reservations are, in the end, actually an advantage to the purchasers of forgings. The price originally charged the customer as a die charge is not the selling price (i.e., cost plus profit) for a set of dies and is not generally even the total factory cost of making the dies. Die-Replacement Charge on Forgings The price paid for the forgings includes a charge known as die replacement, which is a reserve set up by the forging company to compensate it for making a new set of dies when the first set is worn out. It is necessary for the forging company to reach a proper balance between the rate of production, as it affects the life of the dies, and the die replacement cost, so that the ultimate cost per forging shall be at a minimum. This is because the purchaser invests in the original set of dies only, and is not charged for any subsequent sets which may be necessary, the expenses of which are distributed over the forgings by the die replace- ment factor. Each purchaser of forgings, especially when pur- chasing in less than life-of-the-die quantities (this quantity may be anywhere from 100 to 200,000, de- pending on many factors), should preferably select a forging company which he knows to be reliable and seeker . : : . 418 THE IRON AGE vive it the order, either with or without a previous esti- (not a definite price quotation) of its cost. ll bring as many prices iotations, ‘and none of them have any f producing the price which will be charged for the In the first i timates of cost on the mat I r, in everyday language, rut \ the t tor 1s iman, “even as you amount, either for profit, or deducted and Cost Plus a Return on Investment nies, under normal condi- iote on a new piece what they he selling price when sold subse- conditior But, regardless nd the motive behind it, every npany must, OI! the average, charge cost ir? ts investment, or the purchaser will ew source of supply. All forging companies probably) ote on that basis ru If the purchaser “buys dollars” on ginal order he has no legitimate complaint if reased on the second run, which simply that the forging company either has discovered r in estimating or is not willing to continue to e I avervtising mm iving in regard to straight price ds on first runs that, if the forging com- pa ru high, it loses the order, and if low, it i ey I sé ( nel Va ‘ mpetitive bid by a forging company which has the piece before, against one which has made imes, is no more indicative of an unreason- ible price on the part of the latter than the prices on rig quiry were, and for the same reason. How often is heard the plea of the salesman to “quote get started with them.” [The purchaser who “buys dollars” generally gets nd the one who buys forgings for quality will get quality. If the forging company understands what necessary in regard to size, surface condition and f material, it will try its best to supervise its luction to obtain the results desired, the same as the forgings were being produced under the eye of the purchaser. “We aim to please” is no idle saying the closer the specifications, the higher the that no idle saying, either. One Company’s Experience pany had an amusing experience not long We were iccessful bidder (whether lowest or yw) on a large quantity of a single e middle of the run we were asked nother lot of the same forging, but slight- 1 in design. We did, but no order was forth- he reason given was: “Too high.” e later, and before we had completed the buyer who was dealing with us took his inknown to us. During his absence we those polite but scathing letters asking le that two forgings, which they er separate cover, could be produced es, and still be so different, and stat- the t just received was not within striking 4 pecifications and stood rejected, Now, le ke that raise blisters on whoever is tior After the first smoke ttle, someone suggested that it might be lefer any further battle until Uncle Sam, wit! slow but sure methods, delivered that separate cover.” When, a day later, we hurriedly ypened the package, lo! they were the new design and the “other fellow’s” product. A A few hours later a representative of our company was in conference with their purchasing agent, superin- tendent and master mechanic. After they had freely pointed out the error of our ways, we fully admitted all their contentions as regards ‘size, and also (we February 10, 1997 blush somewhat at telling this) pointed out steel had been overheated and ruined. As the: furnishing special steel for the job, that was «) ot thorn. We then asked them to look up the cop, e original order for the new design pieces. Aft. y had done so, peace was declared. There then sted what might be termed “The situation any loves.” A few days later we received their ord High Cost of Rejections The whole point of this is that we were c} , size frequently, running a reducing flame on the fy nace to avoid scaling, and running a low temperatur: to avoid burning (it was a peculiar steel in those re- spects). Consequently we had a higher cost than other- wise, but there were no rejections. Rejections cost many times the value of the | involved, in inspection, delayed production, faulty pro- duction, charging back, and above all in irritation. As it is impossible to reduce these things to dollars and cents, they are not added to the price of the low bid, as they should be for a proper comparison, but are, oh. so surely, added to the profit-and-loss statement at the end of the year. Catalog of American Equipment A catalog and directory of American mechanical equipment having 1076 pages 9 by 12 in., with 2800 illustrations, has been printed in Russian by the Am- torg Trading Corporation, 165 Broadway, New York, purchasing agent of metals and machinery for the Soviet Union in the United States. There are 643 pages of illustrated advertising of American products, followed by a section of 155 pages listing American manufactured products alphabetically with names of makers. Seven thousand items are listed and 45,000 names of firms and corporations are mentioned. A section of the book is devoted to 28 articles by American technical experts on various phases of Amer- ican manufacturing development. Among the con- tributors are: Col. Hugh L. Cooper, builder of Muscle Shoals; Prof. Vladimir Karapetoff of Cornell Univer- sity, consulting engineer of the General Electric Co.; S. Q. Hayes, Prof. D. E. Vinogradoff and other eng!- neers of the Westinghouse Electric & Mfg. Co.; Charles E. Locke, professor of mining engineering, and Edward P. Warner, professor of aeronautics, Massachusetts Institute of Technology; Allen Rogers, professor of chemistry, Pratt Institute; R. M. Washburne, pro- fessor of agriculture, University of Michigan; Norman G. Shidle, editor of Automotive Industries, and others others. Fifty pages are devoted to an economic survey of the United States. To this is appended a full descrip- tive list of all scientific and research organizations, with their principal publications. The Amtorg Trad- ing Corporation recently shipped 5000 of the books to Russia. Fewer Bathtubs Shipped Shipments of enameled bathtubs in 1926 are re- ported by the Department of Commerce at 1,195,142 compared with 1,325,517 in 1925, a reduction of 10 per cent. The reports are from 21 manufacturers, com- prising the entire industry. Except for May and June, every month of 1926 was below the corresponding month of 1925. December shipments were 68,133 bathtubs, a drop of 15 per cent from the 80,271 of November, and still further below the 93,242 of the previous December The most recent month was the lowest in more than two years Orders received during 1926 ran somewhat ahead of shipments, having totaled 1,242,969 units. In 1929 the orders were for 1,390,086 bathtubs. A recently invented electrical detector of fire damp or methane, the combustible gas which is respons!’ for most coal mine explosions, has been developed 3 the Long Island City laboratories of the Union Carbide and Carbon Corporation. Burning Gas and Powdered Coal Boiler Furnace Design for Blast Furnace Gas and Pulverized Fuel, Separately or in Conjunction BY J. GOULD COUTANT furnace gas and pulverized fuel requires special consideration of furnace volume and length of travel; also of the means for maintaining furnace temperatures. Blast furnace gas, as a fuel, differs , ordinary fuels, being composed of approxi- ely the following analysis: 13 per cent carbon dioxide 26 per cent carbon monoxide 3.6 per cent hydrogen 57.4 per cent nitrogen Heat value will vary with the same factors hich affect the temperature of flame and will average about 92 B.t.u. per cu. ft. When burned inwashed, being delivered at the furnace at 250 deg. Fahr., the gas will have a heat value of 95 o 96 B.t.u. per cu. ft., which includes the sen- sible heat. The unwashed gas contains quanti- ties of dust that melts at 2000 to 2100 deg. Fahr., which limits the temperature at which the gas can arrive at the boiler tubes and also the fur- nace temperature; as, when in the molten state, the particles will adhere to the furnace bottom. Best Results with 3 Cu. Ft. per Hp. Furnaces with a volume of 3 cu. ft. per rated boiler horsepower have been responsible for the best results with blast furnace gas. This is ap- proximately the same volume required for burn- ing pulverized fuel in a furnace constructed with only a limited amount of direct boiler heating surface exposed to the flame, and approximates 18,000 B.t.u. liberation per cu. ft. per hr. Burners and flame travel are important con- siderations. Gas burners should be located at ow end of boiler, to provide the longest flame Piturnace design for efficient combustion of blast Per Cent of Total Heat Reflected to Boiler Surfaces Temperature of. 0 Boiler Tubes | 2 o- —- A me 6 = & = fer ea Heat Absorbing Surface “Temperature "F. Fig. 2—Average Heat Transfer to Direct Boiler Heat- ng Surface. The long U-flame method of combustion for pulverized fuel is the basis of the curves at 2450, 2350 and 2250 deg. Heat absorption is increased 25 er cent by the short-flame method for pulverized fuel oS mo rm Nw travel possible. The gas, entering at low. velocity and as high a temperature as possible, is thoroughly nixed with air at the burner. Preheated air accelerates ignition and increases fur- nace temperatures and heat. absorption of boiler, due ‘o heat radiated to direct heating surface (see Figs. |, 2 and 8). Blast furnace boilers, gas fired, and for urning a combination of blast furnace gas and pulver- ized coal, assure maximum thermal efficiencies, burn- oo p> ae A COC ' 2: a Fig. 1. 419 ing the fuel with a small amount of excess air, not to exceed 20 per cent. Pulverized fuel burners are arranged to provide opposing flames to create turbulence, thus completely burning the gases in the furnace. Pulverized fuel Theoretical Temperature of Flame in Boiler Furnaces, °F. Ns 309 3272 3452 eR ut \ rit + S a sts 8B ZFBSE & Theoretical Temperature of Flame in Boiler Furnaces, °C. 180 Theoretical Temperature of Flame in Boiler Furnaces. Radiation loss is 2 per cent burners are of the induced draft type, low velocity, or arranged to receive forced draft preheated air. Boilers designed for burning blast furnace gas and pulverized fuel will show a greater return on the in- vestment if boilers are operated at approximately 225 per cent of boiler rating, 20 per cent of the fuel being pulverized coal and 80 per cent blast furnace gas. Exposed Surface Important The direct boiler heating surface exposed to the fire is of prime importance, as the temperature of ignition, furnace temperature, slagging conditions of gas-fired boilers and steaming capacity of any coal-fired boiler are all controlled by the amount of such surface ex- posed to the fire. One 1600 hp. boiler designed for water floor will operate normally, at 200 per cent boiler rating, at 75 per cent boiler efficiency, burning blast furnace gas. The projected area of direct boiler heating surface is approximately 200 sq. ft. But with pulverized coal it can be operated only at 125 per cent of rating at 12 per cent CO,:. Placing two rows of tubes exposed to the fire and increasing the direct heating surface to 300 sq. ft., it would then be possible to maintain 78 per cent effi- ciency, and 180 per cent boiler rating at 12 per cent CO,, with pulverized coal as a fuel, without the slag- ging of blast furnace dust or coal ash. With two rows of tubes exposed to the fire, the eee ad ETE: aes 420 THE IRON boiler efficiency would Dé approximatel) AGE February 10, 1927 Theoretical Temperature of Gases in Boiler Furnaces 70 per cent with blast furnace gas, unless Analysis Proximate Analysis Composition a small amount of pulverized fuel was Carbon 17.00 Pertent Moisture ass By Volume burned in combination with blast furnace Hydrogen §.3§ Volatile 37.00 CO>= 17.00 e Dittebungh | A/eger 1.58 Fixed CarbonS6.§1 ~ H.0=7 Using a Water Floor o yo Sulphur I./7 Ash 5.54 S02 =0 Pere oa Onygen 8.96 Btu. 3870 Np=75.84 The I difference be- As: 5.94 a er iracterist of blast furnace Pp 50 ; S T T and puiverized l¢ that it Is ap- © - 45 . rent tl me constant-temperature 2 5 40 SS . furnace should be employed. To this end &§& 5*| 5 SONS ( pped with a water +“ > N : ll} a witn >» = . S & 25 | = SHOP : , h and dust may be al = 20 | |__SSO5 iccumulate luring the period £cO IC a. ‘awed | blast furnace © 3S ||. Aadation | oN tnat it desirable to burn Diast Lurnact oo A heaes 7g fe a 1 > Ss 'Y| Aurmtiarg loss ga The furnace would then have an + & 5h} Toei | ¢ surface of 200 Su 9 Ee Fecti ( re nea ing Irtac¢ <o I. V Seer eres Sey The |} er would operate at Z2z2o pel Ga of ot of oy Sus er rating with 73 per cent boiler mow +2 =e =3o2 - erheater efficiency. Theoretical Temperature of Gases Arriving at Boiler Tubes ind d can be swept clean from a ; ‘ oe : : ; a 1 4] NOTE’ -In practice,deduct for45% humidity 100°C-180°F. Also furnace gpewilirs ee radiation 50 °C-90°F. Total deductions high temp. furnaces 1§0°C-270°F. ( t lave i ient Boilers and other turnaces /00°C-/8O0°F ‘ { are VU i ° 7 ’ . . 7, al tent te mate he boiler 4 Fig. 3. Theoretical Temperature of Gases in Boiler Furnaces at aii a all sa sas Different Ratings and Percentages of CO, oe pel aL per ce I iZ é { } 78 per cent efhcienc Use of the water floor eliminates the necessity of furnace temperatures are controlled by the amount of burning a combination pulverized coal and blast fur- direct heating surface exposed to the fire. nace ¢ maintain high economy when it is desired The curves in Figs. 1, 2 and 3 are theoretically cor- rn gas. Consequently it would not be necessary rect, the amount of heat absorbed being that found in perate pulverized fuel equipment at all times. A practice. This has been taken at a constant, to arrive higher boiler efficiency could be obtained if two tubes at the various considerations. Fig. 3 shows the tem- ire exposed to the fire and the boiler equipped with tl ter floor burning 20 per cent coal and 80 per coal when required. Limits in Blast Furnace Gas > ! limited to furnace tem- erature rre nding to the melting temperature of the melting temperatures of ash. I Fast irriving at the boiler tubes must not exceed t t neither must the temperature of As previously stated, High Cost of Workmen’s Compensation New \ employers spend more money on work- pensation, per worker insured, than do em- ployers of any other State, according to a report by the National Industrial Conference Board. This is in part due to more liberal benefits granted in New York, and partly to higher wage levels. For every dollar spent on compensation per worker in New York in 1926, employers in other States spent from 32c. in the lowest to 76c. in the highest case. Compensation in- surance rates for workers in all occupations have in- creased on the average 48 per cent since 1914. But the total cost of compensation for insured employers, excluding the self-insured, has risen in New York State from about $12,000,000 in 1914 to about $55,000,000 in 1925 Changes in the cost of compensation in different lines of occupations have varied greatly during the past decade. In a large group of industries, including, among others, the metal trades and iron and steel, the average cost of compensation per wage earner in New York is found to have increased 320 per cent since 1914. The average wage cost in these industries in- creased 120 per cent during the same period. Total cost of compensation, per $100 of payroll, is 190 per cent higher in New York than in Pennsylvania, and is about double the cost in New Jersey and nearly double that in Connecticut and Massachusetts. In the foundry and machine shop industry, com- pensation per worker now costs over four times what it did in 1914, largely because of increased benefits and larger payrolls. In the iron and steel erection industry, the average cost of compensation per $100 of perature in coal-fired boiler furnaces; Fig. 2 shows theoretical temperature in blast furnace gas-fired boiler furnaces; Fig. 1 is based on the Stefan-Boltzmann law, with a proper constant for practical calculation of heat transfer from furnace to direct boiler heating surface. It should be remembered that the steam capacity of any coal-fired boiler is no greater than the relative amount of direct heating surface exposed to the fire. Also, there is a tendency for ash and dust to accu- mulate on the floor of the furnace, which cannot be removed unless the floor is water cooled, preferably by a cast iron covered floor. payroll has risen from $13.77 to $27.45, or nearly dou- ble, between 1914 and 1926. Wages in Industry Continue High The National Industrial Conference Board, 247 Park Avenue, New York, reports that composite wage data for the manufacturing industry as a whole, cov- ering some 2000 plants in 25 different industries, show that while employment and the total number of hours worked began to decline in October, employment in November, 1926, was still greater than in November, 1925, while total hours worked were only about 2 per cent less than in November, 1925. The significant fact, however, according to the board’s analysis, is that workers in the manufacturing industries in November, 1926, on the average were receiving higher hourly (and practically as high weekly) earnings than they had at any time during the past two years. Their av- erage weekly “real” earnings, that is, their wages measured by their purchasing power, were higher in October, 1926, than they had been at any time since the beginning of 1924, and were higher in November, 1926, than they had been in November, 1925. This, view of the fact that there had been two full years of high industrial activity at high wage levels, the board declares, is the best index of the actual present con- sumption power of the working population, which con- stitutes the greatest market factor. __ “Low-Temperature Carbonization of Coal” is the title of technical paper 396 of the United States Bu- The author is A. C. Fieldner. reau of Mines. What the Corson Alloys Copper Hardened by New Method" Are—Stronger Cable Wire Possible— Many Uses Suggested — Silicon- Aluminum and Siver-Silicon Alloys BY M. G. CORSON ESIDES the high copper-silicon alloys there has ently been discovered a group of four series ‘ ternary alloys, known as Corson alloys, each ng relatively small amounts of silicon in addi- much larger amounts of chromium, iron, cobalt The proportions of the latter metals are so 1 as to form silicides of the formulae, Ni,Si, rSi, CoSi and probably Fe.Si (a). The amount of r present in these alloys varies from a minimum er cent for the high nickel alloys to 99.4 per maximum for the copper-chromium silicon alloys. | four series form a natural class of alloys, which 5 e supplements the one, “Merit in Copper-Silicon published in THB IRON AGB, Feb. 3. The author is metallurgist, 8108 Polk Avenue, Jackson Heights, shed by p@mission of the Electro Metallurgical } \ is considered non-existent; it when crystallizing from ompound Fe,Si er, become possible wey lid copper Liquid x + NinSe 7An Nickel- Silicide, per cent 1234 8 6-1-6 ok Oe Fig. 10 10 —Tentative Constitutional am of the Cu = Ni,Si Alloys Developed by the Author. 12—Hardening Effects in the (= NiSi Alloy System. ‘DCD, Brinell hardness as rolled _ and quenched from 950 deg. EC,, Brinell hardness as drawn % hr. at 500 deg. and slow cooled. A4EDD,, Brinell ’ hardness as enched in oil. excessive hardening which ‘appens sometimes, due to ‘aulty quenching. GF, electric resistivity as rolled nd quenched from 950 deg. H, same, as drawn at 500 deg. d slowly cooled down to 350 Brinell Number 13—Influence of the Time of are amenable to heat treatment in a way that makes them appear to be a counterpart of duralumin, They form pseudo-binary systems, with copper as one com- ponent and a definite silicide, NiSi, Co:Si or CreSi as the second one. The direction of the boundary between the pure alpha alloys and those of a duplex structure (in the constitutional diagram) is such that it is certain that there is an increased solid solubility of the silicide in copper at higher temperatures. Nickel silicide is the most soluble, as much as 7.3 per cent nickel and 1.7 per cent silicon being retained by copper in solid solu- tion at a temperature of 980 deg. C. At room tempera- ture the solubility is very low; at any rate it does not exceed 0.7 per cent nickel and 0.15 per cent silicon. Quenching retains the alpha state of the alloys at low temperatures, while slow cooling causes all excess sili- cide present to crystallize as a second phase. Figs. 11 and 12 illustrate the constitutional aspects of the Cu- NiSi and the Cu-Co.Si series. In a chill-cast bar of an alloy containing, for in- stance, 4 per cent nickel or 2 per cent cobalt or 0.5 per cent chromium, plus a corresponding amount of silicon, the silicide is present in three forms. One part of it is retained by copper in solid solution, due to quick cooling. This part decreases the electrical conductivity and changes but little the mechanical properties of the alloy. Another part (and quite a large one) is found precipitated in the form of microscopically visible crys- tals at the boundaries of the grains of the ground mass. This part has little influence upon the electrical con- ductivity or the hardness of the alloys; it impairs, how- ever, their workability under pressure or pull. Finally, a third part is found precipitated in the ultra-microscopical form. This part does not affect the electrical conductivity; it produces, however, a state of a high hardness and considerable strength. The composition mentioned (4 per cent Ni + 1.9 per cent Si) shows, when chill cast, a Brinell hardness of 175 to 190 and a strength of 75,000 Ib. with 5 per cent elonga- tion. An alloy containing 0.5 per cent chromium shows a hardness of 90 and a strength of 40,000 Ib. per sq. in. The electrical resistivities are 10.5 and 3.7 microhms respectively. At a temperature of 750 to 900 deg. the structure and properties of the cast alloy change quickly. Either a part or the whole of the silicide goes into solid solu- tion (according to the temperature of the treatment) ving at 550 Deg. Upon the 0 fname emirate See ee rr /viness ‘and Blectrie Resistivity fies e618 5 6-1. 2.304 begat Alloy wi t Ni,Si. i. Si Al Hardness; DE = Ree Ni, Si, percent Hours at 550° ity Fig. 12 Fig. 13 421 ee — 422 THE IRON AGE and the remaining grainlets diminish in size and coal- esce into globules. n this way by a high tem- The cast metal changed perature treatment is made soft enough for cold wom either by quenching or by slow cooling in the furnace. However, ‘t is more advantageous to begin by hot working. Alloys containing about 7 per cent nickel are suitable only r hot forging; those containing o per cent nickel n ay be hot forged first and hot rolled after- ward. while those containing about 3 per cent nickel can be hot rolled immediately and given very heavy re- = . ra At certa tage before the final shape and size 800 «+CO, Se Cenp i 2 2S -aeee- & Cobalt-Silicide, per cent Fig 11—-Tentative ( pner-Cobha Constitutional Diagrams of t and Coppe r CoSi Alloys as Devel- oped by the Author are reached, the semifinished product is treated at a temperature of 750-950 deg., according to the nature of the alloy and the amount of silicide present. An alloy with 3 per cent nickel requires not more than 830 deg. to be almost completely homogenized. At 900 deg. its grains become too large and unreliable. Alloys much higher in nickel or those containing about 1.2 per cent cobalt must be treated at 900 deg., while those containing larger amounts of cobalt (about 2 per cent), or containing chromium, are treated preferably at 950 deg. The duration of the heat treatment need not be long, one-half to one hour being sufficient. In the quenched state all four types of alloys are very soft and show at least 50 per cent, in some cases even 70 per cent, elongation in 2 in. The strength of the quenched nickel alloy (with 4 per cent nickel) was found to be 60,000 lb. and its yield point 20,000 Ib. per sq. 0 For the chromium alloy with 0.5 per cent chromium the strength, hardness and ductility are prac- tically the same as for pure copper. Alloys containing cobalt and iron occupy intermediate positions. The alloys can be marketed in the soft state and the sheets may be spun into cups or stamped to the same extent as copper or cartridge brass in short, fab- ricated into different shapes by cold work. The finished article needs only to be put in a furnace and kept at a temperature ranging from 350 to 550 deg. C. for a time. The time required varies from 30 hr. in the first case to % hr. in the second. This treatment makes the alloy very hard and strong. The nickel alloys, for instance, attain a strength of 110,000 to 115,000 Ib., a yield point of 75,000 Ib., a proportionality limit of 50,- 000 lb., with a Brinell hardness of 180 and an elonga- tion of 10 to 18 per cent. A treatment at 350 deg. yields the highest elongation, while a treatment at 550 deg. for a short time results in the highest proportion- February 10, 1927 ality limit. The heat treatment worked out fo, the finished article applies fully to the product of the rolling mill (rods, sheets, wire, tubing) cither imme. diately after being softened by quenching or after being subjected to further cold work in between. __ A particular feature of this second hea: treatment is its influence upon the electrical resistivity, Th. latter decreases enormously. A chromium alloy will show about 2.2 microhms per em’ in the hard state (against 3.7 in the soft one) and the copper-nickel. silicon alloy shows 3.2 microhms against 10.5. Figs 13 and 14 reproduce the hardness and electrical condye. tivity of the Cu-NiSi series, while Figs. 15 to 18 shoy the microstructures of these alloys. The group of four series of alloys described wij probably find a large application in various fields oj industry. All these alloys can be manuufactured in the form of high conductivity and high strength wire. : be used in the construction of telephone lines, cables. trolley lines, etc. In the spun or stamped form they will be found useful in chemical industries as thin walled kettles, tanks, etc. They can be made to with. stand high pressure or vacuum without an externa reinforcement by steel. Roof shingles now made of plain copper can be made of copper-nickel-silicon allo; sheet with a saving of 30 to 40 per cent in thickness while their strength, wear resistance and stiffness will be greatly enhanced. The alloys containing nickel or cobalt (plus silicon) possess a tendency to become cov- ered in time with a lustrous and gniform brown patina while plain copper shows only an uneven covering a dirty-green. All the alloys described can be used t obtain tubing and pipe by the Mannesmann or other piercing and cupping processes, Alloys of Silicon with Aluminum The fact that aluminum and silicon present a com- paratively simple case of eutectic-forming alloys has been known for quite a time. The eutectic alloy of about 10.5 per cent silicon possesses a number of de- sirable properties including the lowest shrinkage any of the aluminum alloys, a good strength, a fair ductility and a corrosion resistance far above that o! most aluminum alloys in the cast state. Castings made of the eutectic aluminum-silicon alloy, called “Silumin” in Europe, are suited for uses in the chemical industry A far higher degree of usefulness and reliability 's lent to these alloys by the modification process, orig!- nally discovered by A. Pacz and afterward much im- proved through the efforts of the Aluminum Co. America. The modifying treatment consists either melting the alloy under a cover of a small amount sodium fluoride or in the introduction of metalli sodium. This latter method (Aluminum Co. of Amer- ica) is much more practical, as it requires a lower temperature and the castings are usually sounder. The modification process probably is quite comp! cated as to its chemical and physical nature, at least no fully satisfactory explanation has so far been ‘ fered. This has not prevented the development 0! ® definite practice which results in good and reliably strong castings as a matter of routine. Metallic s dium, 0.1-0.2 per cent, is introduced into the moite! alloy at 650-700 deg. C. and the melt kept untouched for 20 min. before it is poured. These 20 min. probabl} suffice to complete the process of modification and %- low all excess sodium to burn away. When cast, either in sand or chills, the modified alloy has a very ™™ texture and the individual particles of silicon are hare’) discernible at a magnification of 500 diameters. ““ strength was up to 30,000 Ib. and the elongation * ' per cent against 22,000 Ib. and 3 per cent in the no™ modified alloy. All alloys up to 15 per cent silicon may be used ~ castings in the modified state. The best compositie" lies, however, at 13.8 per cent silicon where 4 strictly eutectic structure is obtained and both aluminum 4° silicon are dispersed to the possible limit. They *™ fairly workable hot up to 15 per cent silicon and cole to about 5 per cent. The wrought alloys show no dis- tinctive improvement in comparison with other alum num alloys. The fine properties of aluminum-silicon alloys &** February to the investigation of a few ternary sys- hin the ranges where aluminum forms the the alloy and silicon is the predominating ad- Dix has shown for instance that it is possible good castings of aluminum-silicon-copper thers obtained aluminum-silicon-zine alloys with what better strength and considerably higher nt than obtainable in the non-modified silumin. positions of this kind are now in a regular use manufacture of certain parts of airplane crank-cases and also cast parts of the air- tructure. One has to bear in mind, of course, presence of either copper or zinc does not en- the corrosion resistance of the alloy. Thus a ng designed to serve in a chemical industry must ide of the purest (iron free) binary alloy only. The sodium treatment may be just as successfully ap- ed to the ternary as to the binary alloys. qT +} { ey ie most successful combination of physical and cal properties of all aluminum-silicon alloys r in the normal or the modified state depends on the purity of the alloyed elements. Not 0.6 per cent iron should be allowed in the alumi- ised for alloying and aluminum containing even s iron should be accepted in spite of its higher price r any casting intended to withstand corrosion or to ~~ ~ contact with compressed gases and vapors. iller amounts of silicon (up to 2 per cent) are n the “Lautal” type of alloys, which represent a er grade of duralumin developed in Germany and vith a slight modification in the United States as (alloy No. 25S). In this case silicon acts as a growth inhibitor while copper takes the part of ictual hardening element. The alloys acquire their mechanical properties after a double heat treat- the first at about 510 deg. for % to 1 hr. followed ienching, the second at 100 to 160 deg. for 20 to icon in small amounts (below 1.0 per cent) is sely introduced into an aluminum alloy of a high gth and high aluminum content, namely the Eu- in “Aludur” and the American “51S.” It is ac- ied in this case by larger amounts of magne- The latter forms with silicon a compound, , which acts exactly like the NiSi or Co,Si in the f the copper alloys already described recently de- THE IRON AGE Fig. 14 (Left)—A 4-Per Cent NiSi; Copper Alloy as Chill Cast; X 70 Fig. 15 (Right)—A 10- Per Cent Ni,Si; Copper Alloy as Chill Cast; X 350 veloped by the author. Alloys of this type always con- tain above 98 per cent aluminum and their properties are developed by a double heat treatment. Their strength is about 12,000 lb. per sq. in. lower, while the hardness and elongation differ but slightly from those normal for the regular duralumin compositions. The absence of copper leads, however, to an elimination of accelerated corrosion, and alloys of this type are second in their chemical stability only to the best aluminum metal and to the hard aluminum of the trade (as hardened by about 1.2 per cent manganese). Silver-Silicon Alloys The binary series silver-silicon represent a case strictly analogous to that of aluminum-silicon. At nearly 4 per cent by weight, or 13 per cent atomic, the series forms a eutectic which cannot be told from the aluminum-silicon eutectic under the microscope. This eutectic alloy may be hot and cold worked to a con- siderable degree and when of that desirable composi- tion, where neither patches of the primarily crystal- lized silver nor primary crystals of silicon mar to any extent the eutectic structure, the alloy acquires a remarkable ability to withstand tarnishing in air containing either sulphur or ozone. An addition of cadmium, tin or zinc (the first is preferable from the viewpoint of workability) permits bringing the alloy to the sterling (92.5 per cent Ag.) composition and opens a way to the manufacture of tarnish resisting