The Iron Age 1927-08-18: Vol 120 Iss 7

THE IRON AGE New York, August 18, 1927 ESTABLISHED 1855 VOL. 120, No. 7 Continuous Casting of Small Parts Production of Nearly 10,000 Castings for Small Elec- trical Motors Attained With Minimum of Labor, Reusing Sand Each Hour CONTINUOUS unit for the manufacture of A small gray iron castings was placed in opera- tion recently by the Elmira Foundry Co., El- mira, N. Y. A complete sand handling and sand prep- aration system is included. This unit is an interesting adaptation of a foundry to a special class of production work and was provided to make possible a large output in a small floor space and to solve the problem of handling an unusually large amount of molding sand in comparison with the tonnage of castings produced. The castings are for end bells for fractional horsepower induction motors used large- ly for refrigerators and washing machines and have thin sections, averaging ¥% in. in thickness and 3 lb. in weight. Were the molds set on the floor and poured once a day an enormous amount of sand would be re- quired in making them. The continuous unit installed has a capacity of 9600 castings per day of 8 hr. re- quiring approximately 22 tons of metal. By minor additions this can be doubled. While the production of castings is large in number, the tonnage is small because of the small size of the castings. The Elmira plant includes three separate foundries and the work is divided according to size and char- acter of the castings. Plant No. 1, used for turbine work, produces castings weighing 2 to 22 tons. This 1 made in machines placed between canvas partitions pass around conveyor, moving toward right. After passing through pouring room they return to point just beyond safety bridge, where the flasks are shaken out and hot castings return in opposite direction on pay conveyor. Shake-out sand and spill sand is returned by underfloor belts to elevators and conditioning plant in center of view, and tempered sand returned to 1-ton hoppers over each molding machine 391 is served by a 35-ton Whiting cupola which is tapped once a day. Here all the molding is sweep work. Medium and heavy castings weighing 500 lbs. to 3 tons are made in plant No. 2, This has a capacity of 60 to 80 tons per day. This unit is provided with two Herman jolt roll-over pattern drawing molding ma- chines for part of the molds, the remainder being hand made. The No. 3 foundry, in which continuous molding and pouring is done, takes care of the lighter castings of from 3 to 500 lb. This building is 560 ft. long and HE drive of the mold conveyor is of a special unique design. This is a caterpillar type chain drive. The chain is placed in a vertical instead of a horizontal plane with the drive from the side in- stead of beneath. With this drive the necessity of a double-jointed driving chain is avoided 120 ft. wide and the continuous molding unit for mak- ing the smaller castings occupies one side. In the re- maining space molds are poured on the floor. The foundry is served by two Whiting cupolas of the con- tinuous type located in a cupola and pouring room at the side of the foundry. The cupolas are operated one at a time, on alternate days. They are mechanically charged by a 3-ton hoist equipped with a special charging attach- ment supplied by the Shepard Electric Crane & Hoist Co., Mon- tour Falls, N. Y. Molds are handled and poured on a Stearns continuous mold conveyor of the endless chain type, 430 ft. long and oval in form. This conveyor moves at a one flask, but molds for larger castings up to 11 in. in diameter are made one in a flask. When the mold is completed the molder places it on the conveyor and clamping weights are set on the top of the flasks while they are moving along the conveyor at the far end, just before entering the pouring room. The cupola is tapped into a bull ladle supported on trunnions and from this the metal is dumped into 150- lb. hand ladles suspended from a trolley on which it is run to the pouring zone. A feature not commonly found in conveying equipment for continuous molding and pouring systems, is a pouring conveyor 28 ft. long, which runs at the same speed as the mold conveyor and on which the men stand while pouring the molds. The mold conveyor passes from the pouring room into the open air, running along the outside wall of the foundry, and then turning back into the building. With this arrangement the fumes are to a considerable extent discharged into the open air. A man stationed at a point a short distance from where the molds are poured removes the weights and places them on a roller gravity conveyor, on which they are carried back to the point where they are placed on the flasks. This con- veyor is the only gravity conveyor used in the system. When the flasks in their circuit reach a point about 10 ft. from the first molding machine they are tilted end for end on the conveyor and dumped on a vibrating knockout. The empty flasks are placed back on the mold conveyor and again travel past the molding ma- chines. Here the molders remove them from the con- veyor and set them on tables at one side until needed. The castings are raked off the knockout table to a hot castings conveyor of the apron type that carries them, in the opposite direction from which the flask came, back through the pouring room into the cleaning room. This conveyor is 300 ft. long, 200 ft. of which is in the open air. It moves at a speed of 24% ft. per min. By the time the castings have reached the end of the conveyor they have cooled sufficiently to be handled by hand. In the cleaning room there is a battery of six Sly tumbling mills for the conveyor output and the necessary grinding machines. After cleaning, the work moves to inspection tables and if passed the castings are loaded on cars for shipment. From each day’s run castings are taken for hardness test and these must show a Brinell hardness of from 142 to 175. Castings are handled in the cleaning room in tote boxes hauled by an electric lift truck. The Stearns mold conveyor differs in design from other conveyors of this type. Instead of having the usual cast iron mold carriages, the conveyor is made up of 24-in. x 24-in. steel cars spaced on 27-in. centers Only one flask and mounted on Hyatt roller bearings. a Seas Diane tiny Overflow Chute __ ‘ Steel Grating Around “Molding a . aa re Molding Machines Machines 4 /4 Gravity Conveyor for Returning Weights NUE AU LANL NNAL ENE AAy/7 Y speed of 22% ft. per min. Molds 2== are made on a battery of twenty : Osborn jolt roll-over molding machines arranged in one line at the side of and parallel with the 4 mold conveyor, spaced 6 ft. apart, av alternate ones working on cope and drag. Steel flasks and metal patterns are used. The flasks are 12 in. x 18 in. x 12 in. deep. For \ castings 6 in. and smaller in di- a h i ameter two molds are made in Cupolas” 392—August 18, 1927, The Iron Age % Pouring Room \ TA ¢ PouringPlatform ZZ an ee Conveyor - \E ‘| Side Wall of Romp} Building Overhead Trolle for Lad/es: ‘ 36 OFF He yd i j HE pouring room. The upper conveyor is the discharge of the hot castings conveyor to the cleaning room. The pour- ing zone section of the mold con- veyor comes in underneath. At the right of the mold conveyor and moving at the same speed is a conveyor 28 ft. long on which the men stand while pouring. Ladles of metal are han- dled from bull ladles at the cu- pola, suspended on hoists from the monorail is placed on a carriage at present, but two flasks can be put on each carriage, thus doubling the capacity to 19,200 castings per 8-hr. day. The conveyor chain is hung in a vertical instead of a horizontal plane and a special caterpillar chain drive is from the side instead of beneath. The advantage of this arrangement, it is pointed out, is that it avoids the necessity of having a double jointed chain which would be required for a conveyor making a complete cycle, were the driving chain placed in a horizontal position. The drive is through a planetary type of speed re- ducer connected directly to the motor and a vertical worm gear speed reducer connected directly to the planetary reducer. All other power-driven units have independent motors and speed reducers. The latter — supplied by the W. A. Jones Foundry & Machine ., Chicago. "eee care is eadeies in the preparation of molding sand to insure the conditioning and tempering required to produce high-grade castings having a very smooth finish. Sand knocked out from the molds is discharged through the shakeout table on to a knockout sand con- veyor which delivers it to an elevator. To this elevator is also delivered sand struck off or spilled during the molding operations. (The molding machines are set above grating-covered hoppers into which the spilled sand passes, eliminating the shoveling of the sand from the floor by the molders.) From this elevator the knockout and spilled sand is discharged over a vibrat- ing screen supplied by the Pittsburgh Coal Washer Co., to separate the sprues and other metallic substances, Spill Sand i Comper Under Gra ted Floor — ‘= _oeghoit- 5 which are discharged into boxes. The sand going through the screen is deposited into a 60-ton bin be- neath the screen and from the bin it is fed by an apron conveyor on a belt conveyor with a magnetic head pulley to catch any metal that may have passed through the screen. From this conveyor the sand is discharged into a double paddle pug mill, in which it is conditioned and tempered. Water is added through a spray regulated by the man who operates the conveyor for tempered sand. The pug mill consists of two parallel shafts with cast steel paddles arranged in a spiral form. The tips of the paddles are of white iron to withstand wear, and are removable so that new paddles can be substituted when required. The pug mill is provided with S.K.F. thrust bearings. Sand passes from the pug mill into an elevator that discharges it into a sand conditioner of a special type, the function of which is to fluff up the sand. It con- sists of a vertical shaft on the lower end of which is a wrought iron spider. The sand is beaten up by the rapid whirling motion of the spider through which it passes. The spider revolves at a speed of 720 r.p.m. Leaving this conditioner the sand is discharged through a hopper on a distributing sand belt from which it is plowed off into 1-ton hoppers above each molding machine. If there is excess sand on the dis- tributing belt it is carried over the head pulley and discharged into the spilled sand belt. Extreme care is taken to keep the proper amount of moisture in the sand. Each hopper of sand is tested sf for moisture content = | by means of a mois- 5 ture meter supplied < \ NComeyor , by the R. W. Me- \\\ Ilvaine Co., Chicago, aa : - S Td f \ Vn} adie and the amount of Overhead Distributing Belt.’ Conalitioner- ry | j len ia moisture is recorded. Conveyor With Hoppers Tempered Sand" m “1 ajfon LI} + This testing is done Elevator ~ ee Bin AIT | by the man operating Hot Castings re ware Screen \— pp i Led the distributing plows. ET LI EE =}=cks HB Gj eo == The sand handling —— _—_—_-—= = t Lb jf —= system has a capacity — = Eig oo oa SS : : , of 60 tons an hour _ Se i a, and the sand makes a Mold Conveyor Drivé * Tailings CAute LAN of continuous unit in gray-iron foundry of Elmira Foundry Co. Total elimination of hand shoveling, and complete circulation of sand at hourly intervals are effected by this self-contained unit circuit of the system in an _ hour, being used over again eight times per day. Core making is a minor problem, as few of the castings require cores. The Iron Age, August 18, 1927—393 ‘ ‘ ’ ‘ t ’ ‘ ' ‘ ' ’ ' ‘ ; ‘ : Changing Mills with Minimum Delay Continuous Sheet Bar Mill Operating After Only 12- Day Interruption—Twelve Stands in All and a construction program enabled the Inland Steel Co. to switch from an existing 24-in. three- high mill to a new 19-in. continuous sheet bar mill with an interruption in production of only 12 days. The new continuous mill, erected at plant No. 1, Indiana Harbor, Ind., is capable of rolling squares ranging from 1%-in. up to 4-in. and sheet bars in widths from 8 in. to 12 in. and weighing from 6% to 54 Ib. per ft. Previous to the erection of the new mill, billets and sheet bars were rolled on a 24-in. three-high mill served by a 36-in. blooming mill. Several years ago, in anticipation of the new mill, a new hotbed, bar piler and flying shear were installed in a location so as to serve the existing mill and also fit into the future scheme when it materialized. In the rearrangement, one stand of the present 24-in. three-high mill, with its lifting tables and manipulators, was retained for use as an independent billet mill for sizes beyond the capacity of the new continuous mill. This stand of rolls is located in line with the run- out from the 36-in. bloomer and about 320 ft. from the center line of that mill. The necessary tables and equipment were retained to provide shearing and pil- ing facilities for the billet mill output. A transfer, capable of handling blooms up to 100 ft. long, takes material from the 36-in. bloomer run-out table and transfers it to the run-in table which serves the new continuous sheet bar and billet mill. (ates preparation of an operating schedule Twelve Stands of Rolls in New Mill The new mill consists of two stands of 24-in. rolls, six stands of 19-in. rolls and four sets of vertical edg- ing rolls located respectively before the first, third, fifth and seventh horizontal stands. Immediately in front of the mill is an up-and-down cut shear having a capacity of 35 sq. in., followed by a set of 18-in. vertical edging rolls, then the two stands of 24-in. rolls. All of these units are driven by one 3000-hp. variable-speed motor. With a space of 24 ft. from the last stand of the 24-in. mill the first stand of the 19-in. mill is preceded by a set of 16-in. edging rolls driven by an independent adjustable-speed motor. The third edger, located be- tween stands 4 and 5, is driven by the mill motor. The fourth edger is located between stands 6 and 7 and is driven by an independent motor. The six stands of the 19-in. mill are driven by one 7500-hp. constant-speed motor through a Falk gear reducer. Rolls for the 24-in. mill were designed as nearly as practicable for a permanent setup and have passes in a single set of rolls to cover all sections that the 19-in. mill is capable of producing. The 19-in. mill is ar- ranged with looping devices between the roll stands. All roll housings are of the open top type, with the bottom rolls adjustable by means of wedges actuated by screws from the front of the mill. Driving Motors and Controls The 24-in. mill is driven by an adjustable-speed Scherbius set through a Falk reducing gear unit. The motor has a maximum speed of 500 r.p.m. and a mini- mum speed of 250 r.p.m. The Scherbius set consists of 394— August 18, 1927, The Iron Age one 3000 to 1500-hp., 500 to 250 r.p.m., 2200-volt, 3-phase, 25-ycle, wound-rotor motor and one Scherbius regulat- ing set consisting of one 650-kva., 375 r.p.m., 190-volt generator, direct connected to an induction motor rated at 900 hp., 375 r.p.m., 2200 volts, 3 phase, 25 cycles, with the necessary controlling and regulating equip- ment. The 19-in. mill is driven by a constant-speed West- inghouse motor through a reducing gear unit having a motor speed of 365 r.p.m. This induction type motor is rated at 7500 hp., 375 r.p.m., 2200 volts, 3 phase, 25 cycles. Both motors and all other electric drive accessories have been placed in a motor room, 220 ft. long by 36 ft. wide, immediately adjoining the mill. The switchboard is located in the middle of the building on the floor level. On the balcony immediately above are the bus structure, switches and high-tension equipment. The master controls are in front of the primary panels so that the operator can see all instruments while handling the drive. The motors can be regulated as to speed and stopped from the mill control pulpit, but starting can be effected only by the operator in charge of the motor room. Planning to Avoid Interference Construction work was proceeded with in two sec- tions: That which could be undertaken without inter- ference with the existing mill, and that portion which would interfere with the existing mill and which, there- fore, had to be performed in the minimum of time. After the motor room with all its equipment was first constructed, the concrete work for foundations up Approach lable, nl Cy | : c a CCE TT ETT a “SkewTable 7) the Tables’ Ap pad able One Stand of the Existing 24-in. Three-High Mill Was Retained (Above, at left). Pro- duction was interrupted only 12 days when changing from the old to the new mill Delivery End (above) of the New Continu- ous Sheet Bar and Billet Mill. Edging rolls are seen before No. 7 stand (No. 8 is at extreme left) and before Nos. 5 and 3 stands (No. 3 is the first of the 19-in. train) Constant - Speed In- duction Motor Rated at 7500 Hp., (Right) Driving the 19-In. Mill. The speed- reducing gear is be- yond the motor Billet Mill --Transter | Scale Prt . Ba MO ii Se oi “s Oe rae 1 *y te | | Scale S— NN Sia amr . “Skew Table \ Billet Yard S —5 Billet Pulpit U ” — \ __ Roerss Mil 19 og cee Flying Shear 4] \ come ee ys} ot on a es Siar TL ee ep ep Coll | (Pulp Lee q tit | Ch | acy Fr alt a aD dh dp oO up ¢ Ht = | oo | 2500 | = u — % — Moor } “Gears tr am Motor. : : “Speed Reducing Gears ; (| 0 50 100’ 150 200 \\ \\ The Iron Age, August 18, 1927—395 i ! Two Stands of 24-In. Rolls (Above) Are Followed by Six Stands of 19-In. Rolls. The steel moves toward the left, passing through a shear and a pair of edging rolls before entering the first 24-in. stand and through another pair of edging rolls ahead of the first 19-in. stand to the pinion stands was placed. A careful schedule was next prepared showing every operation in con- nection with dismantling the existing mill, installing the 100-ft. transfer, remodeling and re-erecting exist- ing tables and installing the mill proper. The old mill was shut down on Friday, Feb. 5, and the first bar was rolled on the new mill on Thursday, Feb. 17. Manufacture of Domestic Heating Appar- atus and Steam Fittings Stoves and warm air furnaces, gas and oil stoves and appliances, and steam fittings, including steam and hot-water heating apparatus, are covered in a report on manufactures in 1925, issued by the Census Bureau. Copies may be obtained at 5c. from the Superintendent of Documents, Government Printing Office, Washington. a Wk . ., $ 5 — 7 Ga a ' There were 789 establishments engaged in this line of manufacture in 1925, compared with 824 in 1923. The wage earners were 89,774, with total wages amount- to $130,278,639 during the year. The value of products is given as $493,232,937, of which amount $320,003,253 represents value added by manufacture. Both the lat- ter item and the value of products are the largest ever recorded for these industries. The subdivision shows $228,929,985 of products in steam fittings, and steam and hot-water heating appa- ratus; $123,497,794 in gas and oil stoves and appli- ances, and $140,805,158 in other stoves and warm-air furnaces. The two first items made the largest records ever obtained, while the last item showed a drop of 9.6 per cent from the high record made in 1923. Details in the 15-page pamphlet show operations by States and many particulars relating to the manu- facturing. The Two 24-In. Stands Are Driven by a 3000-1500 Hp. Scherbius Set Through a Falk Reducing-Gear Unit, the Latter Appearing at Left (Inland Steel Co.) 396—August 18, 1927, The Iron Age Possibilities of Fuel Economy Limitations Imposed by Character of Steel Mill Equipment and of Product—Calculations for Specific Cases Presented BY E. F. ENTWISLE HIS is a discussion of a paper which, under the above title, was presented by H. A. Bras- sert, consulting engineer, Chicago, before the Eastern States Blast Furnace and Coke Oven Association at the winter meeting held at Pittsburgh, March 4. Mr. Entwisle, who is assistant general manager Steelton plant, Bethlehem Steel Co., prefaced his remarks with a statement that Mr. Brassert’s treatment had covered the matter so completely as to preclude great detail in many of his points. “It is obviously just as impossible for me, in discussing his paper, to attempt to analyze it in detail. It seems to be proper, however, to emphasize, by means of some specific data, the fact that such economies as are possible, are possible only when the coke ovens and blast furnaces are so operated as to give the maximum of excess gas for subsequent steel plant operations.” ONDENSED into a single sentence, Mr. Brassert’s (3 conclusions are that the ultimate in fuel economy (aside from the question of financial economy) is to produce the maximum tonnage of finished steel prod- ucts with the purchase of the minimum quantity of fuel for carbonizing or for heating, and, where any surplus of waste gases or heat remains, to convert such surplus into the maximum amount of power for sale to outside consumers. At least two points must be taken into considera- tion in applying such a yard-stick of economy to any individual plant: (1)—The make-up of the plant it- self, what its products are, to what extent these prod- ucts are finished, the method of steel making, proximity of the coke ovens to the blast furnaces, and other similar considerations and (2)—The practical economic consideration, or, as I called it above, the financial economy. In other words, can a plant, in view of conditions for any location as to equipment already installed and as to fuel prices and their probable fluctuation during the life of the equipment, afford to spend the money required for equipment necessary to obtain the ulti- mate in fuel economy? Or would the lowest operating cost be obtained by purchasing the additional fuel re- quired by a lesser heat economy? Specific Analysis of Two Conditions Each plant is a problem in itself, but there are cer- tain basic facts that apply in every case. Before it is possible to determine the procedure in any case, a study must be made of the situation along the lines of the following figures. I have taken for analysis and comparison two rather different conditions. First is a plant in which 100 per cent of the steel is made by the Bessemer process, and probably some- what representative of the German plants to which Mr. Brassert refers as having already established themselves on a heat recovery basis where the only coal required in the entire steel plant operation is for carbonizing. Second is a plant more nearly repre- sentative of average American conditions, in which I have assumed 20 per cent of the ingot production by the Bessemer process and 80 per cent by the open- hearth process. Figures in the tables show approximately the sur- plus heat production from the coke ovens and blast furnaces for both of the conditions outlined above, and also the total amounts of heat necessary to carry on the various operations of steel making, heating and rolling. I have assumed in both cases that the ingots are rolled into blooms, the blooms reheated and rolled into billets and the billets reheated and rolled into commercial bars. If any of these operations can be omitted, there will be a corresponding surplus in the amount of heat available. If additional operations are required beyond those stated, additional amounts of heat will be necessary. Basis of Discussion I have assumed that in the Bessemer process 1.25 tons of iron are required per ton of ingots produced, and that in the open-hearth operation 0.60 ton of iron is required per ton of ingots. It is obvious, therefore, that, in a plant making all of its steel by the Bessemer process, considerably more iron will be required per ton of ingots produced ana that, to produce a greater quantity of iron, additional coke will have to be pro- duced. Hence the surplus gases from the coke oven and blast furnace operations will be substantially higher per ton of ingots produced in the 100 per cent Bessemer plant than in the 80 per cent open-hearth plant. Mr. Brassert’s figure of 13,160,000 B.t.u. has been taken as the heat in the blast furnace gas per ton of iron produced. The heat required to produce a ton of open-hearth ingots is taken at 4,000,000 B.t.u. The complete figures for these two conditions are tabulated. Operation on the 80 per cent open-hearth basis will result in 40 boiler hp. hr. recovery for each ton of open- hearth ingots produced. This works out into a recovery of 1,070,000 B.t.u. for each ton of ingots produced, as in Table II. In addition to the amounts of surplus heat avail- able (Table II) there are further possibilities through the dry quenching of coke. From the present status of this development there are thus available in the 100 per cent Bessemer plant 904,000 B.t.u. per ton of ingots produced; in the case of the 80 per cent open-hearth plant, 535,000 B.t.u. per ton of ingots produced. From Table III it appears that the heat required, for heating only, would be 3,200,000 B.t.u. per ton of ingots produced, whether operation be 100 per cent Bessemer or 20 per cent Bessemer and 80 per cent The Iron Age, August 18, 1927—397 open-hearth, provided the blooms are charged hot. If they are charged cold, heating would require 4,700,000 B.t.u. for either case. Rolling of the ingots, also, would be independent of the steel-making operation. Power is figured at 110 kwhr. to convert each ton of ingots to commercial bars on motor-driven mills. On the basis of 20 per cent thermal efficiency at the switchboard of the power plant, this represents the requirement of 1,870,000 B.t.u. for rolling each ton of ingots produced. Consequently the total heat requirements for pro- ducing steel and for heating and rolling, per ton of ingots produced, would be 5,570,000 B.t.u. for 100 per cent Bessemer operation with blooms charged hot and 7,070,000 B.t.u. for blooms charging cold. Similariy, with 80 per cent open-hearth and 20 per cent Bessemer operation, the requirements would be 8,370,000 B.t.u. for hot charging of blooms and 9,870,000 B.t.u. for cold charging. Surplus Heat Available Comparison of the total surplus heat available with the total heat required to carry on the operations shows that, in the case of the 100 per cent Bessemer operation, there is a large surplus of heat beyond the amount required for producing the steel and for heat- ing and rolling. This surplus, available for sale out- side of the plant, consists of the coke oven gas not needed for oven heating and all of the tar and breeze, unless some subsequent operation is carried on, beyond the assumed production of commercial bars only from all of the ingots produced. In the case of the 80 per cent open-hearth opera- tion, however, the balance is very much closer. It is unlikely, due to the fact that the steel production, heat- ing and rolling proceed at a different rate from the production of coke and pig iron, that all of the steel production, heating and rolling requirements can be completely taken care of by the combined heat surplus. For the open-hearth requirements, however, the heat in the tar, which can be readily stored and used as re- (Wonwasnvveenns vvvovcennenvexsunvencvnsengeetoeereconenenvveraensnvecsissystsnevvossesnevevesyceveresveenveesoony sesvernonecsneveveunenseerawertoyseDeeastsstoevoeeettannyrueeanererpenmpesyn sv evubenen Table I—Heat Surplus from Blast Furnaces and Coke Ovens 80 Per Cent pen- 100 Hearth and Per Cent 20 Per Cent Biast Furnaces Bessemer Bessemer Iron per ton of ingots, tons....... 1.25 Ee Ss. UN £ RR a 13,160,000 Gas consumed by stoves, per cent. . 25 Gas consumed in blowing, if gas- 0.73 13,160,000 25 engine driven, per cent......... 15 15 Gas consumed in blowing, if turbo- ee, ek eer eee 25 25 Surplus gas per ton of iron pro- duced, if gas blown, per cent.... 60 60 Surplus gas per ton of iron pro- duced, if turbo-blown, per cent. . 50 50 Total heat in surplus gas per ton of iron produced, of gas blown, B.t.u. 7,900,000 7,900,000 Total heat in surplus gas per ton of iron produced, if gas blown, B.t.u. 6,580,000 6,580,000 Surplus heat in blast furnace gas per ton of ingots produced, if gas nCMere so be A bade hie bn dhe es 9,900,000 5,750,000 Surplus heat in blast furnace gas per ton of ingots produced, if EE iiss oo Cloke ve oe bo 8 8,250,000 4,800,000 Coke Ovens Tons of coal per ton of coke pro- SES i SE es ae ear 1.33 1.33 Cu. ft. surplus gas per ton of coal EES RS PE eee 7,000 7,000 Assumed fuel ratio at blast furnaces 0.90 0.90 Cu. ft. surplus coke oven gas per ton of iron produced............ 8,400 8,400 Net B.t.u. of coke oven gas....... 475 475 Net B.t.u. in surplus coke oven gas per ton of iron produced........ 4,000,000 4,000,000 Net B.t.u. in surplus coke oven gas per ton of ingots produced...... 5,000,000 2,900,000 Gallons of tar per ton of coal car- EE. bin Ck cea baie ebb, > eee 9 9 Gallons of tar per ton of iron pro- pe yt hs Sane, RES 10.8 10.8 Gallons of tar per ton of ingots PE Ks vealsae ou bSatabee ea» 13.5 7.8 Total B.t.u. in tar per ton of ingots SE + 56 «bbs bebe does 000% 2,080,000 1,200,000 Breeze and domestic coke, in per- centage of coal carbonized...... 4.0 4.0 B.t.u. from breeze and domestic coke, per ton of ingots productd. 1,608,000 940,000 venues NED resvaasucacnoraNDeRnOrHnEErN quired, constitutes an easy means of synchronizing the open-hearth demands with the coke oven production. If there is no outside market for surplus coke oven gas and tar, the open-hearth operation can just about be carried from the coke ovens. Our figure of 4,000,000 B.t.u. per ton of open-hearth ingots is below average present practice in this coun- try. But it is a figure that is being reached in some plants and, with proper facilities and control, can be met regularly. If there is a market outside of the plant for the coke oven gas and tar, either producer gas, coal or oil can be substituted at the open-hearth for the fuel requirements. Or the coke ovens can be operated with gas producers or with the surplus blast furnace gas, in which case the coke oven gas thus re- leased will take care of approximately 60 per cent of the open-hearth fuel requirements. Exact Balance Difficult to Attain A surplus of blast furnace gas is shown as being sufficient to carry on all of the heating of the steel for normal rolling, from ingots to commercial bars. In the case of the plant where the blast furnaces are blown by gas engines, there is sufficient surplus gas and open- hearth waste heat steam to carry on both the heating and the rolling requirements. The difference between the irregular occurrence of the power and heating de- mands of the steel plant, however, as compared with the even rate of production at the coke ovens and blast furnaces as previously referred to, makes it unlikely that this balance can be exactly met. But, by eliminating the power requirement, sub- stantially all of the heating requirements, which fluctu- ate somewhat less than the power demands, can be sup- plied from the surplus blast furnace gas. Some gas producer capacity or fuel oil would probably be re- quired, to compensate for such differences as might develop between the rates of operation of the blast furnaces and rolling mills. Power for the requirements of the plant can be supplied by using a portion of the surplus blast fur- nev CHMENUOERAMESALOU OONKOENLECQNADGTL 1108040060714 UEHBOERNDEDOOONY GA WeeEy uenoceeDoeeNOCAvieELLRAUTEn nev tert er eneunentD® vee UREN PARENTAL 6080000 VENNEE RENN ELON Table Il—Total Surplus Heat 80 Per Cent Open-Hearth 100 Per Cent and 20 Per Cent Bessemer Bessemer Gas Turbo- Gas Turbo- Blowing Blowing Blowing Blowing Blast furnace gas.. 9,900,000 8,250,000 5,750,000 4,800,000 Coke oven gas..... 5,000,000 5,000,000 2,900,000 2,900,000 St bwhonkioeeu eee 2,080,000 2,080,000 1,200,000 1,200,000 Breeze and domestic ED onde ah vacate % 1,608,000 1,608,000 940,000 940,000 Open-hearth waste POE crevice xeer Gear aban make ees 1,070,000 1,070,000 MOORE c0vcudns 18,588,000 16,938,000 11,860,000 10,910,000 Table I1I—Heating Requirements per Ton of Ingots 80 Per Cent n- Ope 100 Hearth and PerCent 20 Per Cent Bessemer Bessemer B.t.u. required per ton of ingots DERE assert velcanwebsabbics Ab¥eEles 3,200,000 Bessemer blowing B.t.u........... 500,000 100,000 Heating fngote Bt... ac-cecescccs 1,000,000 1,000,000 Heating blooms (hot) B.t.u....... 1,000,000 1,000,000 Heating blooms (cold) B.t.u...... 2,500,000 2,500,000 pg eee 1,200,000 1,200,000 Total B.t.u. for producing steel and EY Soa dns 6 aria hate aa Walaa 3,700,000 6,500,000 or 5,200,000 or 8,000,000 *The lesser figure is the requirement if blooms are charged in heating furnaces when hot after blooming; the greater figure is for a condition where blooms are reheated after becoming cold. eammmmren 510 10005 51855 0c ese nee rene eeonvnnvn never eayeenegaonaneneseeiay es eeevuennnannn sweeney eaten( oe cetn ey jensnescameneyyo yey cunt rey enoenree coer enpervpreeersngess1ssereangeensecancens tiny canvencoiantoteuenperteoserusanveanuanan amunaneronvveetocanvonnwenvtroenas i ecsnenvuensuneaunangntveasocnteraqnoeneuatane rUOPUaEs tvEbLLUrTYFRENUnEOeROOLENELET ROUPEDNAEEYVCE A EPNOEREORG CORSTRURNREREPPORGLLEBUCEDOTOONDEL th 08 1OROGOUEONEEOEDESLESOASEOOOSUREOTSOOD 398—August 18, 1927, The Iron Age nace gas in gas engines and supplying the resulting deficiency in heating by either producer gas, coal or oil, or A portion of the blast furnace gas can be burned under boilers and power generated in engines or tur- bines, and the resulting deficiency in heating taken care of by either producer gas, coal or oil, or The entire power load can be carried on a steam station fired with the cheapest grades of fuel available and driving either engines or turbines, or The power may be purchased from an outside source, leaving all of the surplus gas available for carrying on the heating operations. Each Case Is a Separate Study It must be realized, of course, that the figures that I have given constitute only an approximate heat balance. It is substantially correct for a given set of conditions, but many variables, such as the quality of the coals used, the relative percentage of the total ingot tonnage made by the Bessemer or the open-hearth process, the degree to which finishing operations are carried on, ete., will vary the figures considerably from those given. For each particular case, a balance along the gen- eral lines indicated should be set up. From it can be determined, taking into account fuel and labor costs and existing equipment, just what combination is the most economical for that particular set of conditions. In no case, however, can either the coke ovens or blast furnaces, without penalty to the subsequent operations in the steel plant, afford to use more than the absolute minimum of their gas for their own operations. Tapered Steel Plates for Construction Work Suggested Use of a New Form of Structural Steel—Considered for an Oil Storage Tank HELLS of large steel tanks for storage of oil are made of five or six horizontal rings of narrow plates, each of uniform thickness. The dimensions of these plates have not changed materially since they were governed by manufacturing limitations of iron plates two generations ago. But these shells, according to a Pittsburgh consulting engineer, could be constructed of upright taper-rolled plates, shipped from the mills to the tank site and there welded in final position with vertical seams. This would save about 20 per cent in total weight of steel used, and all of the costly field riveting and calking. The accom- panying sketches and tables were obtained from the engineer. TABLE II—STANDARD TAPERS SUGGESTED Rate of Reduction in Thickness Designation of ——— A Rate of Taper Fractional Decimal No. 00 1 in 1667 0.0006 No. 0 1 in 1250 0.0008 No. 1 1 in 1000 0.001 No. 2 2 in 1000 0.002 No. 3 3 in 1000 0.003 No. 4 4 in 1000 0.004 No. 5 5 in 1000 0.005 No. 6 6 in 1000 0.006 No. 7 7 in 1000 0.007 No. 8 8 in 1000 0.008 No. 9 9 in 1000 0.009 No. 10 10 in 1000 0.010 TABLE I—TAPER PLATE STEEL OIL TANKS Comparison of main characteristics of 35,000-bbl. tanks:—Six-ring standard tank and taper plate tank, both riveted and welded. Items Compared Standard Number of pieces in shell....... Plates 120 Angles 80 Weight of shell (without rivets) 122,000 Ib. Field-driven rivets in shell...... % in — 4,800 5g in.— 5,700 ye-in.— 7,000 Total—17,500 Total lin. ft. of calking......... 5,300 (a) 95,315 Ib., if vertical seams lap. ------- 95-6 Diam. Outside of Shelt- - - -- 5 Outside Elevation of Tank Shell Oe at e500 Half Section A-A Illustrating the Character of Work for Which the Tapered Plates Are Recom- mended Riveted Tank— een Saved by Use of Taper Plate, Welded Tank Taper Plate Per Cent Taper Plate 40 66 48 40 50 24 Average 58 120,000 Ib. 2 92,370 Ib. (a) 4,600 3% None 4,400 23 6,600 5 15,600 Average 10% 3,500 34 Rel =(T-#) p= Gt) T= #+(RxL) . t= T-(RxL) L-G Z Plates Rolled fo No.00 Taper " a4375 (i) we ——— ae dag at oe ee “Taz 100(1°)-* -2.268( %2+) L 072 €-7%5) Plates Rolled to No./0 Taper " = ———— ay 2 LI57S(1 he) me ae be ons C Se) "3 —————eeeneS) sant} ay 10067 CH) F- 6 G (4) ~~~" Diagrams show Edge Thickness of Plates Examples of Tapers, as Shown in Table II The Iron Age, August 18, 1927—-399 ——_———— oe = Studies Internal Fractures in Bars Sulphur Prints Indicate Cause in an Impure Streak Inherited from Segregation in Ingot Top BY ERNEST F. DAVIS AND ROBERT J. PETERS* quality specifications and seemingly sound, will for some mysterious reason break during tooling operations. The appearance of the fracture in some cases indicates an internal rupture but sometimes it does not. Chemical analysis of drillings obtained in the usual routine manner give no clue to the funda- mental cause of this breakage, and microstudies in the region of the failure often do not reveal the true rea- () ‘conity spect bar stock and forgings, bought to 3%-in. bar with internal rupture son for such extreme weakness in what should be first class material. A number of explanations have been offered for such failures, all of which are logical assumptions based on the evidence at hand and the circumstances surrounding the failure. In many instances these may be secondary causes. In a forging the fracture is sometimes attributed to excessive upsetting, to cracks developed from the strains of shearing, to improper forging temperatures, to the practice of quenching forgings in water, or to some other mal-practice in the forge shop. If this breakage occurs while machin- ing hot rolled bars it may be said that the trouble is due to cold centers in billets before rolling, to too high finishing temperatures, or segregation in the bars. If the bar has been cold drawn fracture may be blamed on overworking and too heavy reduction. ; Sometimes the pieces made from defective bars or forgings are fabricated in such a manner that they do not break during machining but crack subsequently in hardening. Then the cause may be assigned to some defect in the heat treating practice. But worse, the steel may survive both machining and heat treat- ing and not fracture until the part is placed in ser- vice. ._It may then rupture immediately or last for six months or longer. If it does not break until after a period of service we are liable to assume that it failed from “fatigue.” All bar stock is more or less segregated with a concentration of impurities in the center of the bar. A bar of steel may be regarded as simply an elonga- tion of the original cast ingot. Although refined by working, reduced in size and subjected to longitudinal movement of the constituents, yet the same elemental metals and metalloids are present in the bar which existed in the ingot when it completely solidified and these are in approximately the same relative position in the cross section. The impurities deposited in the *Respectively chief metallurgist and metallographist War- ner Gear Co., Muncie, Ind. 400—August 18, 1927, The Iron Age center of the ingot, although extended over a greater length, are still in the center of the bar, as they were in the ingot and billet. If compounds which are re- jected during the crystallization phenomena should be- come entrapped in the center of the ingot, on account of solidification before they could arise and become ex- pelled, we may safely assume that a core containing these metalloids would persist in the bar. Furthermore this area containing high sulphur or high phosphorus would evince the recognized physical properties of high- sulphur and high-phosphorus steels rather than assume the properties of the outer areas of purer metal. It is a well established fact that steels containing too much sulphur (0.20 per cent or over) cannot be safely rolled or forged due to danger of rupture on account of the weak, brittle sulphur eutectoid present. The fusing point of iron sulphide is considerably less ee ee Longitudinal and cross-sectional sulphur print of 3- in. round bar. Long central crack extends into un- segregated metal than that of steel (approximately 2200 deg. Fahr.). Since forging and rolling temperatures are frequently at this elevation the sulphides are no doubt pasty or semi-fluid, so that they offer little resistance to rolling or forging strains. Furthermore sulphides exist as membranous films around the pearlite, thus producing weak grain boundaries. The result is that the longi- tudinal tension of rolling produces minute cracks in the segregated core wherever sufficient concentration of sulphur exists. Further reduction by rolling may develop these cracks for a considerable distance into the body of purer metal exterior to the core. A rup- ture not % in. long in the segregated core may be torn by rolling strains into a fissure 2 in. or more across. A bar apparently sound on the outside may therefore consist of a number of internal ruptures which would never be discovered by visual inspection of the outer surface. A particularly bad example of this type of defect was recently found in a bar of 3%-in. cold rolled stee) of S. A. E. 1020 analysis. The chemical examination of the steel from drillings obtained transverse of the bar gave no indication that it was otherwise than first class material. The analysis was as follows: Carbon 0.18 per cent Sulphur 0.043 per cent Phosphorus 0.025 per cent Manganese 0.496 per cent This steel was machined into flanged bushings hav- ing a drilled and reamed central hole 1% in. in diameter. The machine operator found a crack in the hole, although the outside of the piece showed no evi- dence of flaw. Microstructure adjacent to this crack showed normal constituents of pearlite and ferrite, and revealed no cause for the defect, due to the fact that the area causing the rupture had been drilled out during the machining operation and the fracture had extended for a considerable distance into good sound metal. Cross sections were then made of the bar itself and it was discovered that large ruptures from one to two inches in diameter existed at intervals of 5 or 6 in. at right angle to the bar length, while minor cracks about % in. long were present at shorter intervals, few of these extending beyond the segre- gated core. The sulphur prints shown were made with bromide paper on a transverse and longitud- inal section. The transverse specimen was in the exact location of one of the major fissures. An in- tense concentration of sulphur was apparent wherever one of the larger or minor cracks appeared. Judging from the intensity of coloration, between 0.50 and 1.00 per cent sulphur exists in these areas; surely high enough to make any steel hot short in rolling. Samples for analysis of the core were then taken by planing along the length of the core to a depth of 0.010 in. and for a width of % in. These analyzed 0.21 per cent sulphur, which of course represents the average of the core segregate and not the highly con- centrated sulphide patches which produced the actual fissures. The prints made in connection with this investiga- tion show the difference in sulphur content between the core and the surrounding metal. A sulphur con- tent of 0.05 per cent will scarcely tinge bromide paper moistened in dilute sulphuric acid. (The low-sulphur areas of this bar analyzed 0.043 per cent sulphur). It should also be noted how the small crack originally formed in the core has extended into the low-sulphur metal. The print made of the transverse section in- dicates that the sulphur nucleus in the center has been the original cause of the rupture. The existence of this condition may be more com- mon than believed. It is not confined to this particular grade of steel, for we have found it at intervals in high priced alloy steels in just as aggravated form. This defect is especially dangerous because of the difficulty attending its discovery before fabrication. As this example aptly illustrates, the composition of the segregated core of any bar is very important in determining steel quality and excessive concentration of metalloids is always liable to produce undepend- able steel. These internal ruptures may account for many unexpected breakages of parts not severely stressed, and may be the starting of many so-called fatigue failures. Insufficient cropping of ingots and billets is pos- sibly the major cause of this defect, because it seldom exists in more than a few bars in a heat. Cadmium Plating Resists Rust Addition Agents in Electrolytic Bath Give Mirror- Like Deposit of Good Throwing Power BY C. H. HUMPHRIES* ARLY in 1919 the Udylite Process Co., Kokomo, K Ind., made commercial applications of cadmium on a variety of articles, chiefly such things as corset steel, razor blade stock, piano wire and iron and malleable castings for playground equipment. At that time there were no other commercial uses of cadmium metal for the protection of iron and steel articles against rust by either electrodeposition or hot dipping and no plating solutions of any commercial size or vol- ume had been prepared. At the time there was a marked paucity of informa- tion regarding the deposition of cadmium in forms suitable for finish or of any value to the electroplating art. One article by Armstrong had been printed in Metal Industry in 1911. A few patents have covered the application of cadmium as a protecting medium for steel, notably the Russell and Woolwick British patent dated 1848. These patents indicated its possible uses, but there had not been developed suitable solu- tions from which cadmium could be deposited in the proper physical form. Since cadmium and zine are similar chemically it was assumed that the electrodeposition of the two would have a close resemblance, but such is not true. In the electrodeposition of zinc two types of solution have been employed, one a sulphate solution and the other a cyanide bath. Cadmium plate deposited from acid solutions or from solutions of neutral salts had been of no commercial value. Laboratory work had indi- cated that cadmium deposited from cyanide solutions * Research director, Metals Protection Corporation, In- dianapolis. gives a different type of deposit which had promise as an electroplating finish, but even when deposited from double cadmium solutions it was very little better in appearance than that from sulphate solutions. It responded to ordinary color buffing in an encouraging manner, but the chief drawback to the application of cadmium alone was its inherent softness. Formulas which were developed in the laboratory and which apparently gave suitable deposits were not found to be satisfactory when made up in large volumes. There- fore, such formulas and the technique of application had to be devised. Furthermore, some addition agents had to be found which would materially change the type of electrodeposited cadmium with regard to its micro-crystalline structure, its appearance and its hardness. Such addition agents have been found. They change the former soft white coatings which easily water-stain or grease-stain and which were quite easily abraded, to coats which have a high luster similar in appearance to hot dipped tin and possess a surface more resistant to rubbing. The cadmium deposited from the solution which was finally perfected is quite adherent to steel and does not lift when the steel stock is flexed or twisted. It differs considerably in this respect from hot galvanized coats. It is also necessary for the deposited coat to be uniform in thickness and free from pin holes. Fortunately the final type of cadmium plating solution evolved had a good throwing power which resulted in coatings fairly even in thickness over ordinary con- tours. The chief consideration determining the thickness The Iron Age, August 18, 1927—401 of the plate is the kind of service expected of the pro- tected articles. Obviously a brass part in a radio set is exposed to different conditions from the cap nut on a disk wheel. In the former the average thickness of the cadmium coat is approximately 0.0002 in., while on the latter the specification calls for 0.0006 in. Cadmium is substituted for zinc as a protective coating because its deposits tend to be more even in thickness, more continuous and freer from capillaries. In addition, the silvery white color is more attractive than the dead flat, easily stained, electrodeposited zinc coat. Cap nuts on disk wheels have been used on one popular make of automobile for over three years, re- placing sherardizing. The change resulted in better service from a protection standpoint and also improved appearance. The cadmium surface stayed white, whereas the buffed sherardizing coats turned black after about one season. The following table gives some of the resistance values of cadmium coatings in the salt spray test: Salt Spray Test 20