The Iron Age 1922-08-17: Vol 110 Iss 7

New York, August 17, 1922 VOL. 110, No. 7 MOET 2X + Fe Pee WA Steps in Stamping a Draw- Bolt Tube Single Stamped Part Replaces Complicated Assembly—Cost Lowered and Design Improved—Methods of Manufacture Outlined BY N. T. THURSTON ITH a view to reducing costs tube the manufactu e was ten cents per and improving construction piece less than in the old style, and the labor expense the draw-bolt tube used on in getting the assembly together and in place in the a widely known fireproof safe, ready to install, was eight cents less per piece. safe was recently re-de- This gave a total saving of 18 cents per piece. As to signed, a single stamped weight, the old style draw-bolt tube was about part being devised to re- times heavier than the new stamped tube. place the former compara- The old tube was constructed of two tively complicated assembly. seamless steel tubing as shown A saving of 18 cents per as well as an improvement in that part truction of the safe. stamped part is shown above, the com- previous draw-bolt tube employed being 1. The draw-bolt tube is used as a hich the bolts on the door of the safe ‘ door is closed and the bolts thrown. two principal reasons for re-designing bolt tube. The first was the fact that aving to be fastened to the front plate 1 as a ready means for conducting out- vhich the safe might be exposed in case S1X pieces of one ( + the draw-bolts themselves, causing fast to the sleeves. The second reason ¢ of expense. In the single stamped Toledo, Ohio in Making Stamped l the operations are as follows: educe; 5, finish shape >, trim 7 lo The 4 letermine the approximate number of drawing 0] Pere eens 8 402 THE IRON AGE ~# » ’ iy idsheditdl NL La aad ! oR mnatior Die As the pum h i f i bla 1 he punch continuing down and etal around the plug threaded on both ends and slipping inside the larger tube. Both tubes were set in position opposite the holes in the bracket and the nuts screwed up on both ends of the inner tube thus clamping the tubes to the bracket. To insure a smooth and uniform surface inside the center tube it was reamed The assembly was then ready to be put in place on the safe and pot welded. In manufacturing the stamped tube a good grad drawing steel was used. This steel was furnished 4 In. In width and 0.050 in. in thickness and was ckled and oiled. Only two annealing operations were found necessary. The method for determining the ap proximate number of drawing operations necessary to bring the piece to size ready for trimming and shaping the flange at the bottom and cutting the slot in the side is shown Fig. 2. The first operation was _ to cut the blank and form it around the punch to the hape shown, the blank being cut 3 3/16 in. in diameter id drawn to a length of 1 5/16 in. and to a diameter 2 in. This work is done on the combination die shown in Fig. 3. The die is mounted on a cast-iror base and the punch turned up from a 44-in. bar of tool teel, the die being composed of a tool-steel cutting edge forged to a wrought-iron base with the tool-steel plug located in the center. A tool-steel draw-ring rides nn the tops of four cold-rolled pins, % in. in diameter, which in turn rest on rubber buffers placed unde? the dis As the punch descends the blank is cut from the strip steel, as it is fed across the die, the draw-ring holding the blank firmly against the punch which con tinues on down and forms the metal around the plug. Un tne up stroke of the ram the compre ed rubbers force the draw ring to follow up the punch. At the op of the stroke the positive knock-out pin force the cup out of tl punch and it drops loose on the { ~ } aad l } ie i 4 } } | | } 1) 4 L bt Sg BS SSS SS Fis { ID { Sex i Ope tion The leng of the cup is increased 14 in. and the diameter de creased by the same amount Before this operatior the cup is annealed and washed August 17, 1999 top of the die, to be knocked off by the o Bs. a vents in both the punch and the die ; oo E confined on both sides of the cup to escape. ») s 2 rs the stamping from buckling and teari; \ a ; press No. 74% was used to do this work To prepare it for further drawing th oughly annealed to a cherry red, whicl internal strains in the metal. It is previou solution of one part of muriatic acid and water, the purpose of this being to loo which invariably forms on the steel du while red hot. The next operation, done on a Bliss increases the length of the cup % in., 1 5/16 in. to 1 13/16 in., the diameter being time decreased % in., from 2 in. to 1% for this work is shown in Fig. 4. This t on a machine steel base 8 by 14 in. a) plug, and draw-ring are of tool-stee! ground. The operation of the die is sin the previous one, the descending punc! draw-ring down with it, thus compressir under the die. On the up stroke of the ring follows the punch on its upward f A | r ’ t , j k po ‘ 4 yv \ a “1 i | ‘ > ? i SG + ~~ Ki I ( fu ra ys | Dect neg th I) I ed l shown ibo the top of the stroke the knock-out pin out of the punch. Immediately before tl the stampings are washed in a soap a! ture, which serves two purposes. Fu all scale not removed by tumbling the an! and second, it serves to lubricate the cup, t! ing the drawing operation. The prese! P detrimental to the dies, causing them y necessarily. Vents are provided in thi l plug as in the die used in the previous ope! The third operation still further length of the cup by % in., decreasing by the same amount. The die, shown mounted on a machine steel base, and parts are tool steel, hardened and grou! struction of the punch is a little different usually employed. In this design tool : only where needed. The machine-steel pu! y A is in two parts which when screwed togethe! F . . *s tool steel punch in place. The principal reas type of construction is that in hardening is less likely to crack than if it were faste! machine punch holder by means of screws being a flagrant cause of spoiling tool hardening. This work was also done on a Bhi press, and the operation of the die the same described. At this point the stamping goes through 4, annealing, the process being the same 45 = sree 1 Q299 eT ht et i =a } } esd i y j - g <— 4 In., decreasing the diameter by i forming the flange at the ba ides of the tube. The constru if the die, is similar to the two ibe to size, both as to its diamete) it the base in relation to the sid ymplished in the fifth operatio s mounted on a machir steel i structed as previously described, ikelihood of its being spoiled du also to economize on the amour The knock-out pin is screwed from shifting out of position. the sixth operation, is a trimming base of the tube with the prop: ised 1s shown in Fig. 6. It cast-iron base, the punch being VI I fitted a tool-steel cutting a 4 in. set screw. On the Dp ocated two too it through the trimmed-o scrap ‘ ; 1 ; NN j Upe it Y Is Cut g } the Tube, the Die Employee ng Shown Above IRON AGE 403 rings that accumulate around the punch. The cutting edge of the die is of tool steel, held in a cast-iron matrix. This work was done in a Toledo No. 5 press. The notch in the flange is used to gage the stamping in the slotting operation which follows The final operation is to cut the slot in the side of the tube which is done on a Toledo No. 5 press, Fig. 7, the tool being carried ising tne tool snown on a cast-iron base which holds the tool-steel plug. The punch is of tool steel and is held in the cast-iron holder by means of a % it set rew The slugs fall out as the tube is pulled off the plug, after each operation of the press The purpose of the slot, as to permit connecting the draw-bolt itself, which seen from the illustration, draw-bolt mechanism to the provides the means for throwing the bolts out and in A, hole s drilled and tapped into the the sleeves. side of the draw-bolt, a screw run into the hole and the throw mechanism fastened to the screw The simplicity and effectiveness of this design is apparent The average production of all the operations throughout a run of 100,000 finished pieces was about 000 a ten-hour dav The dies illustrated and de scribed were designed and operated by the Ackli Stamping Co., Toled UT Improvement in Unemployment HARRISBURG, Pa., Aug. 15 Although a number of ron and steel plant Pennsylvania are in imminent ianger of being forced to clos iow! because of a hortage of fuel, a ght improvement in employment ynditions was reported during the last half of July, ding to the semi-monthly report of the Pennsy! ’epartment of Labor and Industry just issued \ total of only 18,450 iron and ste workers was reported without employment on Aug. 1, as compared » 20,050 without work on July 15 and 25,500 on July 1 The decrease approximate 5S per cent Four of the eleven emp ment districts of the State ported more men without employment in the meta { ‘ trades than during the preceding fortnight two, PI delphia and Harrisburg, reported fewer me! thout employment; four reported no change; and the elt entn office, Re 1gding na ist Deer! reopened ana no report 1S avallabDie or the prec¢ { 4” period. Unemployment con ns throug it the State as a ole, exclusive of the mine trade d the railroad nop showed a sl ot} t mprovemer! t during the same perio The 11 offices reported approximately 92,000 without work on Aug. 1 as compared to 101,000 re There hopmen and mi! norted inemployed DY the 10 offices $s oT July 15 1 til irge numbers The British Empire St ation, Sydney, N. S., office reports that 12 steamers are engaged in the export of iron ore from Wabana, Newfoundland, to Germany, via Rotterdam About three quarters of a lillion tons will have been exported before the end of the year. These shipments are being made on an order the British Empire Steel Co. received a couple of months ago for 4,000,000 tons to be exported to steel companies in Europe. Rey ee gt. Pas ro 7 , a ; ¢ * \ Y Ppt. Stainless Steel at ih Lemperatures r at Tras Th; Da . cs ‘ : at} . | Heat Treatment Which Produces the Greatest Strength for Use in Valves of Internal Combus- tion Engines a BY H. J. FRENCH* 5s é [AINLESS steel, containing about 0.3 per cent ing temperature which produces maximum hardness orks carbon and 13 per cent chromium, has been’ js not that which produces the best tensil ; ‘ successfully used at high temperatures, notably erties at ordinary temperatures, i.e., best com. . ip in valves in internal combustion engines. Quite binations of strength and ductility.+ Naturally the probably more extended application will be made question arises as to which of these two hardening : * : methods is most suitable for steel whic} to be S17 i T T pron zi . . : D1 wee vey subjected to high temperature service and h solely | Ur in mind two series of tensile tests were — >} —4—— throughout the range 20 to 550 deg. C. ic. The steel was first oil quenched from either 955 a] ¥ or 1150 deg. C. and subsequently tempered at 675 ; 4 | ; deg. C. The first of these methods of iis 160 produces excellent combinations of st Les i Pil th t ’ Q | t 0 4 — jf j 4 Ee or = 995 | . | ee : | Peatment 665° n0% | ( seltinnhbdattiamnbdiaane - I et end ~4. 4 4 dee eo ne ‘ | L 1 siniiecnieailliiameiealle a » 4 4 mnerature 0 t A | a p : . or NS J , i I Elevated 7 peratu of ; “kS-1- Ste Oil Quenched from Either 9 ( C | | : rempered at O76 Deg. | = 90 200 300 400 500 600 100 B00 ; . Mn., 0.24; 5 wt sae Temperature,deg.C ik aS é per * Bre ng strengu taken as the load at-fracture (in Fig. 3 Strength and Elastic Properties of § s ) f rec ed t ( | ) it Various Temperatures as Reported by |] » ind the Author Breaking strength is take! ; along similar lines in the future on account of its it fracture (in Ib.) divided by the reduced mn peculiar combination of desirable properties after ee suitable heat treatment. It has already been shown that the high quench- ductility whether or not the steel is su °] t RB ‘ 1. W oe tempered, while maximum hardness is pr Si¢ sureau OL Standards, ashington 1isnec ‘ “ i . 4 by permission of the bureau with moderately rapid cooling from th ,, iFrench and Yamauchi: The He ut Treatment of a High- around 1150 deg. C. A single and relative! ec) is Chromium St jour. 8S. A. E., , No. 1, p. 103 (July, ; sad : 1920) tempering temperature was chosen in order tha . ‘y = x = , % able I tt pari of Tensile Properties at Varwus Temperatures of Stainless and Carbon . l 2 High Temperature Properties of Various Steels Compare ‘* R 0.3 C, Steel (Values represent per cent increase ( ) from figures given in column 2) ’ I ties of Ne« ° n zed Carbon Ste ; «? ‘ (0.32% C Air Cooled Quenched and Tem- Cold - Rolled Boiler Heat-7T mS from 850° C.) pered Carbon Steel Plate (0.25% C.; Re- less Stet f (0.33% C.: 840° C duced + In. from 12.7 Water; 540° C. Air) » In. Thickness) Oil v oe 4 —~ . At roon a 74,350 + 34 +11 At 300° C 83,16 25 4 ‘ At ( 21.880 L 41° 178 = © Dean ain 43,400 . +30 f At 300° C an 25,7 61 +18 At & & 2Se +928 ; °. j Elongation i per cent At oom 23 39 ; # At 3¢ , 29 23 At U ( 44.( ] . . Reduction of rea, per ¢ Me At room ‘ 57.4 L 18 3 ‘ } At 300° C oe 30 +114 0 At 550 q* J $7.8 ne *Values obtained by extrapolation of curves from 470 deg. C — August | its might be of widest interest as tem- w operating temperatures (which may «ould of course result in quick softening ; | when first placed in service. 7 nee evident from Fig. 1 that the higher mperature (1150 deg. C.) produces about 10,000 lb. per sq. in. stronger neratures than that similarly quenched C. However, this small increase is F the expense of a very large proportion I60deg.C. —————— Elongation has decreased about iction of area has dropped from values nd 80 per cent to less than 20 per cent the entire range considered. more striking illustration of the effects of the high temperature quench mination of fractures, two series of produced in Fig. 2. Coarsely crystalline ybtained with little or no elongation served in the series first quenched from Proposed Duties on Manganese and Tungsten ON, Aug. 15.—Declaring that the United ts tariff making has adopted one sys nodity and another system for another tor Pomerene of Ohio in the Senate ed attention to the proposed duties on tungsten. was on the subject of potash, which declared should come in free for the ests in the country, stating that it strated that sufficient quantities of ed in this country to make it com le. “The same situation,” he said, omanganese, tungsten and other alloy was perfectly clear from the debate he Senate that such manganese and had, as well as other alloy ores, are low re ls a very great deal of uncertainty ey can ever be produced from our de ally profitable quantities. The ques- to me is this: t if Lriff ° } ind tungsten, and thet \ } ‘ ve th ? f ouraging odu I I P to Ul res that are used E ; her he } ‘ s potash, why 1 er answered that the proposed duty ; the protection of the American indus- merene said further: 1 here in the course of the argument, luty on the alloys would add $10,000,- the cost of steel to the consumers. I Ss were generally admitted. I do not demonstrated that you have deposits m which manganese or tungsten can mmercially profitable quantities. Of personal knowledge on this subject, 245 deg.C. 1922 THE IRON AGE 405 955 deg. C. The latter likewise show much finer structures. Unlike carbon steels which are strongest and at the same time most brittle around “blue-heat” (300 deg. C.) the strength of stainless steel decreases steadily with rise in temperature. Confirmation of this can readily be obtained from the work of other investigators as shown in Fig. 3. However, com- parison with the properties of carbon steels in normalized, cold rolled and quenched and tempered 300deg.C. 415deg.C. 550deg.C. Fig. 2 Fractures of Stainless Steel Broken in Tension at Various Temperatures Top row: Oil quenched from 1150 deg. C. and tempered at 675 deg. C Bottom row: Oil quenched from 955 deg. C. and tempered at € leg. C Each pair of samples broken at temperatures indicated. conditions (Table I) shows some decided advan- tages for stainless steel. It has very much higher strength and limit of proportionality in the range about 550 deg. C. where most carbon and structural alloy steels show a decided “weakening”; at the same time it retains good ductility. However, its advantages at lower temperatures, between 20 and 300 deg. C., over quenched and tempered carbon steel of similar carbon content are not so marked. and I am dependent on what the steel people say with regard to it. They are convinced that such deposits do not exist, or, at least, that they have not been discov- ered in such quantities as will justify an attempt to pro- duce them in this country.” General Refractories Co. Absorbs ‘Three Other Companies Announcement has been made of the absorption by the General Refractories Co. of the Pennsylvania Fire Brick Co. with works at Beech Creek, Pa., the Hays Run Fire Brick Co., Orviston, Pa., and the Standard tefractories Co., Claysburg, Pa. These acquisitions will give the General Refractories Co. a daily capacity of approximately 900,000 refractory brick, making it the second largest producer in the country. Coincident with this development, the company has surrendered its West Virginia charter and has been incorporated under the laws of Pennsylvania. The West Virginia com- pany was capitalized at $5,000,000 (50,000 shares of $100 par) of which $500,000 was held in the treasury for the absorption of foreign subsidiary, the Gen- eral Magnesite Co., Czecho-Slovakia. The Pennsyl- vania company has a capital of 180,000 shares of no par value and has issued $4,000,000 6 per cent bonds, to provide funds for refunding of current obligations, to furnish working capital and for the payment of the companies just taken over. Fire hazards connected with industrial operations and how to eliminate and control fire dangers will be shown at a fire prevention exposition to be held Oct. 2 to 7, at the Twenty-second Regiment Armory, New York. It is proposed to show the latest developments in fire-safe construction and also to demonstrate the proper appliances to be used in fighting and preventing fire. A. E. MacKinnon, 405 Lexington Avenue, New York, is chairman of the exposition committee. wielnthgitebil 13 ent 406 THE IRON AGE TESTS WITH SPECIAL STEELS German Results on Various Chrome-Nickel Steels at High Temperatures A LONG paper by Prof. H. Edert, giving the detailed * results of experiments carried out at increasing temperatures on five alloy steels, appears in the issue of Stal d Eisen, June 22. The steels were in the shape of 25 mm. rounds (0.984 in.) furnished by the Friedrich Krupp Co., Essen, and were tested in heat treated condition as supplied by the works. The com sition of the steels is shown in the table. ( f S) Steels Used e 7 > 6 r e fn nree stee¢ nad peel! yuer ned no ind e fourt quenched at 900 deg 1 oll and drawn 650 deg. | ! ind the fifth quenched at 1200 deg. Tensile tests were carried out at ordinary tem ire, and at 200, 300, 500, 600 and 700 deg. and some cases at 800 deg C Brinell hardness tests at 0, 100 and 300 deg. ( Also shock tests and bending sts were mad Details of the methods of heating the amples and carrying out the tests are given in the iginal paper, and the results are shown in a very in series of diagrams The low percentage chrome-nickel ste els, Nos. 1 and were found to be easy to work. They have a fine tructure and take a good polish, and are suitable as istruction materials for parts of machinery with exacting requirements where the least possible weight required. They show great resistance against alte ating stresses and shocks and also against separate heavy blows. It is recommended that in such cases the special parts be properly designed and large fillets be rovided as the oss section changes. The steels can be used for temperatures up to 500 deg. C., The chrome-vanadium steel, No. 3, is more difficult machine than those mentioned above, but still can Large Lathe for Chilled Rolls \ large roll lathe built recently by the Reading Iron Co., Scott Foundry dept., Reading, Pa., is shown the accompanying illustration. It has a capacity for irning a chilled roll 42 in. in diameter by 120 in. ength of body. It is driven by a 20 hp. variable-speed motor, the speeds of which range from 400 to 1600 r.p.m The main spindle bearing is 7% in. in diameter and all gears are machine cut. The face plate speed is four-tenths of a revolution to one and six-tenths revo- itions per minute. Bearings are liberally proportioned August 17, 1999 be worked fairly well. It has a remarka ture, very suitable for wearing surfaces, a: as construction material for parts with quirements, because of its resistance t : stresses and shocks. It can be used up t but great care must be used if these tem) to 600 deg. C. because the special props heat treatment are lost. : The high percentage chrome-nickel st noticeable because of its great resistance and chemical action. The test pieces deg. C. showed no coating of oxide. The machined with care. In regard to its other special properties, it is very simil: percentage chrome-nickel steels. t can, used as construction material where the are for tenacity and toughness and amount of resistance to chemical action. 1 ture limit is about 600 deg. C The high percentage chrome-nickel ste a fine nickel like color and like the othe a good polish, and notwithstanding its low Brinell hardness shows considerable 1 abrasive wear. It can be machined but w ( ilty than steels Nos. 1 to 4. It is necessa the speed of turning or sawing or els too's. This steel is very susceptible shape, because of its plasticity. At a cle: can be forged something like tool steel a condition is comparatively easily shaped pressing or Stamping. The most important property of this nickel steel is its remarkable resistan action; for instance, a polished section et acid solution in alcohol for 5 hr. was not tacked to show the microstructure. Hyd (1 per cent) in alcohol was necessary fi This steel withstands high temperature: ; the other steels and annealing for 8 hr. at 100 shows very little surface attack. Polished other test pieces can be left without care i tory for a year without being attacked. It ca Is 4 for parts of machinery, if consideration low elastic limit and the parts made corr ling larger. It is suitable for places where 1 iI rust, ability to take a high polish, resista water or other corrosive agents, or to h tures are required. It cannot be magnetiz and shows very great resistance to the forn . Cracks, and the entire construction embodies th needed for the heavy service for which was designed. The total weight of the lathe s! ; 35,000 Ib. Enough recoverable bituminous coal demands of the next 290 years, at present 1 sumption, lies in the Pennsylvania fields, accordin: E a report of the State Bureau of Topographi logical Survey. The figure is given as 43,830,5! net tons, after deducting from the total known capac of the fields the unrecoverable coal and wast E amount already mined is put at 5,519,775,000 p iim aaa Lathe for Turning Chilled Rolls The capacity is for rolls in. in diameter by 120 in. length of body. A <-!- is used THE IRON VETAL SCHEDULE sak Gusietie atten wae: ck ee ‘ , nee Probable in Final Consideration ‘° re sume ble Ww artic oe a the FP | = ne a 7 tec States select nd lescr irt f the nited 2 of the Tariff Bill State I » OF il with } ported articles f ‘ wheneve ~. Aug. 15.—The metal schedule of the , # will be changed little, if any, from ; sali catedioaien | a ee when the measure is voted on by os Kivi abiioreanaaite eae En gps irda\y of the present week. Beginni! yy { pal ¢ \ if t ne cente : 1 . tT’, = Seat Senate started to vote without fur e | ites mmittee amendments not disposed CESUEO 39 , N now Th t rer ve iter than 10 p.m. Thursday it will irther debate on all pending individual When the bill is brought to a final vote +] The import co ale ed as e price at which Saturday, in accordance with a una! np } . +1] f ¢ ¢ tne article Ss tre ffered oO! { I 1e ordinary ivreement, 1t Whil have been befor tna : ; : . i > 4 , course of trade in the usual wholesale quantities for four montns. Discussion of ne meta : : ' | exportation to tn ‘ state pius when not I 1 about six weeks of this time. I a . I ) ‘ , cluded in such p1 ( iry expenses, exclusive eTraovdly parikulariy with regard oO ; ; : Ne, f customs duties ng su nported article ind the ferroalioy section, Dy tné ’ “gigs ' the United Stat when comparea witn the torm + hy hea ’ itte y) hy nee ed by the Committee on Finance Penalizing Discrimination nanges nave related to the ra . ° y ? Tt ? Y nat rT £ - from the free to the dutiable , , aise! ~ , ane + i n the duties on ferromanganese An : en . ‘ Y ecl1mnnort i } y y nad at “ S ne ¢ na mall increase in the duty on fluo en supported b: ind steel make1 Che = edule as a whole now does not ment provide la t ; yuntry does not an , merican commer hat ¢ rlity f treatment whic} he schedule as it passed the Hous American mime , jVainty VY eatme aan : t is th merican 1 vy to grant. tl reside ha not likely that there will be much he America 544 ' President . the no yr to take yrs iraati< y res ne j nec yn between House and Senate ce ne pows an ra easu and, r me ' | ‘ as essary, apply an « irg t is necessary, however k etal schedule itself when it s Sf - ar Ys I ‘ A : ‘ iry an eve for the President t find atter investigation, tnat tnere ’ P s a discrimination he additional duties are limited Work of the Conferees ngs toma to the xtent of the ad rimination, but lf the diserim tr, follow after the hi 0 t0lOW Siver we Ol ation is maintained and continued, the importatior where he original measure w the merchandiss ay be prohibited entirely >. , +} y t : 5 1} r one ear ago It is * Considerable interest bein manifested in the wicluU wer of the Senate Finance Committee appointment « f the Senate conferees. While accord re S pe?! t iT . » \ l 5 ‘ . ‘ . — 4 ‘ . . . : } es begin their work early next week ing to precedent the three ranking Republicans and er has said that every effort will « the two ranking Democrats on the Finance Committee ( e measure reported out of conteren would be named, it seems likely that this custom will not eek and to nave it enacted into iaw e followed in the present instance This is due to tion campaign begins. In the event the fact that Senator La Follette of Wisconsin, a strong a are i. he - * n confer opponent of the tariff bill, is the third ranking Repub ‘ re Ct] he Republicans mat } ' , erore election, the hepublicans ma} lican, and it is doubted that he will be appointed. In e at tne present session, because I h evel hat ‘ } ‘ is been ndicated that cal reaction, should the measure not Senator Dillingham of Vermont wil] be named in the bi e to operate and to be understood befor: nlace of Senator La | ette i Malgn 18 ended. Republi ans der y em : intend otherwise to hold the neas e until af nt of contention in conference wil South House American valuation plan is t " Reductions in Pig Iron Rates from the er election. , : WASHINGTON, Aug. 15 Reductions in rates on pig he Senate plan, which provides fo1 , ' ae iron from the Birmingham, Ala... district to Ohio and subject to the provisions of the so- : : LM yer oO ne yooe 10n oO [ oO M ssissippi river rossing aré proposed in Speiden » iriff amendment, which was adopted , tariff supplement filed with the Interstate Commerce this form tariff i ew in the annal , ‘ \ y of ariff Bey ae - . Commission, to become effective pept. 1. Carriers north ff legislation. The question of cor ee ee of the Ohio river have not joined in any of the reduc raised by a number of Senators who : : ; : s ; tions, so that joint rate are not to be reduced and oO the ian because of what they de 2 Pp ear : fla 1€) consequently the decreas n rates to consuming points nger of transferring the taxing power ere : a. ” a S nortn oft tne river ar) from combinations will be ve branch to the chief executive 1 due to the action of the Southern carriers only. The Proposed Flexible Tariff reductions to be mad ire proposed in addition to those : , that became effective July 1, when the general 10 per Senate granted authority to the Presi nt de . ce crease went into operation It had been pre viously intended by Southern carriers to effect joint = rates with Northern lines, as to make them appli nent of a flexible tariff were con able to consuming points 1 rth of Ohio 1 er. such as The much mooted question of , ecrease the rates in the pending July 1, 1924. The original proposals nicayo. was disposed of easily in tha The proposed reduced rates in gross tons are $3.53 incinnati, Cairo, Ill., New Albany and Evansville, amendment adopted DY the Senate, Ind.; $3.24 to Louisville and $4.24 to St. Louis Pre Tariff ( ommission, in addition to vious Ww July 1, the rate now proposed to be $3.53 wa mpose ; ry le , 4 irectea + > ~ 7 , in oat i ed upon it by law, 1s dire¢ ted Lo $4.50. At present th rate is $4.05. The rate to ers costs and costs of productior Louisville was reduced from $4.13 to $3.71 and the yy ly to dyestuffs and coal-tar chemi io ng, producing, or manufacturing cen rate to St. Louis was reduced from $5.74 to $5.16 when tates of articles of the United State the 10 per cent cut went into effect. The through ne commission it is practicable rate from Birmingham to Chicago was brought down Ooms and costs of produ from $6.67 to $6.01 at that time s. producing, or manufacturing centers f articles imported into the Un opinion of the commission sucl ' The Chase Metal Works, Waterbury, Conn., has of production are necessary for com added to its fleet of tractors four new towmotors, the costs or costs of production in the product of the Towmotor Co., Cleveland. rs ‘ Electric M ive j ; » * » > ye ’ ae ectric Motor Drive in Steel Industry ; » Mee) la Mill Requirements for Adjustable Speed—Considerations = ) of the Flow of Metal Under Rolling Pressure and Its Effect on Power Demands : > BY GORDON FOX* (Concluded from page 341, Aug. 10) ; AVING reviewed briefly the more general mill rolling to obtain a constant finishing ten 7 types, we may now consider the characteristics maintain accurate gage and section. ri ® ¥ of the motors suited to their drive. It may be desired to adapt the mill sp¢ SH Mills revolving in one direction only may require’ to the heating of the furnace, or the rate ye . either a constant speed or an adjustable speed. Con- In a roughing mill slower speeds are des “ tinuous blooming and billet mills, sheet mills, three-high heavier drafts are to be taken, as the meta > 7 plate mills, rail, structural and merchant mills, are among the rolls better. . : Adjustable speed is of particular advar _ ——> finishing rolls—commonly a limiting facto _ —— 4 tion. If adjustable speed is not provided, jee | ee all products must be that suited for the slo : ———_—————= ye Where two or more stands or mills ar Pid : : ey it will usually be necessary to adjust the y ij es to suit the others. This refers especially Toi oo cee een a aa” ing and finishing groups of continuous or ' ri L oe “1] lh tic ’ ave a. & — Li ! ' mills, where the metal is in several bf , " taneously. In mills of this general type rei] ; ris ement Diagram 1 Rolling, in advantage to be able to vary the relat W h A; Is the Original Area, Ao the Final Area roughing and finishing rolls, according u Widt Orig I t | Let The « I a , ] { ose frequently equipped with constant speed drives. Some of the newer mills are arranged for adjustable speed where the older mills managed with single speeds. : Most constant speed mills are provided with wound rotor induction motors, both because of the suitability : f this type and also because alternating current power is more readily available. Flywheels are used with many of these drives. The synchronous motor offers possibilities for application on some continuous mills ; which run at constant speed and fairly steady load, F : ind which cannot well utilize flywheels. But it has 2 insufficient starting torque where it is desired to re- ° verse or back out a cobble. It can, however, develop ‘ : ufficient torque to start against mill friction and in v ertia, and offers some advantage as to efficiency and S power factor. Dynamic braking can be employed for a : juick stop, if desired. t There are many reasons for the requirement of A. adjustable pet 1 for some mills. Among these are the fo ving : Lighter materials may usually be handled and rolled ls it igher speeds without straining the mill or over 24 loading the motor. It is usually desirable to roll the ha , lighter sections as fast as possible, not only for pro ; ‘ iuction, Dut aiso to prevent excessive cooling. 5 ; hi lhe skill of workmen in handling the piece betwee —_——_-- ; ‘, passe may limit the mill speed As this condition is Ton tune. dearees Fahr ; ibject to change and improvement, it is desirable to be ' ‘ able to adjust accordingly. 3. Curve Showing the Variat ; ’ ~? ‘ Some speed adjustment may be desirable to make : er ee : < a . 4 ip for variations in roll diameters. These diameters ae ee ; eg may vary as much as 20 per cent from original to final elongation, and to apportion the reduction mills as desired. Fe It may sometimes be desired to roll some unusually An adjustable speed drive is used at “ ; ; heavy orders at low speeds to minimize the strain on mill of the Inland Steel Co. at Indiana H oo the mill or to limit the power peaks, particularly with to enable the piece to be entered at low pu ised power. enable the speed in the pass to be adapted 8; ur Some qualities of steel may dictate the use of lower length and section of the piece. A low entry § ny J peeds and lower temperature of rolling of particular benefit in rolling some stru It may be of advantage to adjust the speed of involving deep flanges. b ° *Electrical engineer Freyn, Brassert & Co., | o. Th [Here follow considerations of | S ‘ eS ee Se we tan ne eae oe a motors suited electrically to the se’ 7 ei dE oy of some phase of the steel indu quirements outlined above.—EDITOR. ] win) gs 408 of mill and drive are determin > motor size demands consideration. St re largely empirical, being based experience. ave some measure by which data ns may be extended in its application wn as to the flow of metal in the roll nrecise formula for power consumpt “The governing factors are understo empirical methods have been develo; ition. mand of a mill is composed of three c alia ‘tion load is considered as the dem Specif Power ( W W ith! I sents Reve I I Mill Rolling |! i } VI Rolling Reheated | oO ( nuous Roug! gM inning empty. This demand is in and THE IRON ed, } eel on However, as mills differ, it on ing ion rd, ed ym- j int torque with power in proportion ue of the friction load may be dete approximated by comparison witl Reversing mills involve an element » the imparting and absorbing of tl elerating and reversing the m ileulated from weights and radii of members based on a selected rate K'lywheel effect is also an inertia load notor as the speed drops and wi load during acceleration periods. ident to rolling is taken na 1C ind 1n¢« he friction of the metal with d the increased friction at It is evident to theoretical ' ions. tnat so oa 7 4 ea almost entirely lling. It has power required s consistent, pro- ng conditions main- pecial shapes in tems as side dis- collar rust complicate the extent that no able and determi- must be based .on pressure, ime of nNoat -ation metal dis- are used as ile for power deter- ple rolling. It has Fig. 10. Le ally that the power (P: the r a the power required for displacement the caicu { similar shapes, » © @® @ @ pad Aug Chart from 10) AGE 409 consumed is proportional to the volume of metal lisplaced. Referring to Fig 7, HP sec. is onate to L. (A:-A,). 1as also been found that power demand is cl the logarithm of the elongation. log E.) The pass both depend upon the by the number of desired. It is limited by ( propor- he osely proportional to (HP is proportionate to volume displaced and the elongation in a given draft. This may be dictated available and reduction the } ; mill and 19 the passes strength of the by the allowable peak demand on the motor or on the power system. The possible draft is limited by the ability of the rolls to “bite.” The larger the rolls the greater the draft that may be taken without exceeding the limiting angle of rolling, which corresponds to an are of about 30 deg. on the roll periphery. The draft seldom exceeds 30 per cent, and is more commonly 15 to 20 per cent. Some steels deve p! edges if heavy drafts are The draft is as rolling progresses. In rolling plate, for 1e heavier drafts are taken on the first passes while the hottest. The i ; then thicker in the ce » eliminate this, taken. ften varied ; instance, t piece 1S spring of the rolls be nter r causes tne plece to the draft in the ? later passes must be conservative. It is probable that, with relatively heavy drafts, the power consumption is increased by the fact that the average distance of displacement of the metal must be greater. There are required per unit of several the power volume displaced or per unit of Foremost temperature. The power required is closely the ten- le strength of the metal. Fig. 8 shows how the elongation. proportionate t tensile Sli¢ of steel varies with temperatur The usual range is from 1800 to 2300 deg. Fahr Cold requires about twenty tin the power of hot per unit of displacement. It is evident that ‘ific power consumption in the later passes may e relatively high From the power viewpoint it is obviously desirable to roll at temperatures as high as possibl From the viewpoint of quality of steel it is neces- sary to avoid too hig i nitia emperature more- over, finishing at lower temperature iy give added For instance, a thin plate rolled from,a given ia will have gvreatel init te? : engtn tnan a thick plate from the same , due to greater density and finer grain incident to the additional rolling and lower finishing temperaturs \ we hing temperature nay aiso De Stal I to gage The qua te iy influence its rolling power rhe compos of stee 1O€ not greatly affect its trengt at rolling temperatur l high carbon and all ‘ tee should not e heated above 2000 aeg. Fahr., for fear of burning and oxidation of alloy They are therefore commonly rolled at lower temperat and The ires, thus require more power per unit displacement composition of the steel affect the action of the steel] in rolling, rather more than e power requirement. > the Fig. 2 Rolling 7% x Mill into 7% x Shown in 0.315-In Continuous Roughing 2-In. Blooms Skelp ir - wd a : | ‘ : a ma s ti id} 41u THE AGE August 17. IRON it is not possible to state any single value of unit of displaced metal to cover all conditio have been drawn from test data on varioy s ce _— mills. These curves take into consideration, in 4 p> q ; . r tical way, the modifying factors, particula) ae r ; = of cooling, and serve as a guide for forecast s 68 * quirements of proposed mills of similar cha) silat’ ; b>. 9 gives specific power consumption curves f > : | r al ing blooming mill, for a three-high plate * ; , aan reheated slabs and for a billet mill rollir " . - zs . blooms. , These show, for instance, that when th é +“o-< been reduced to about 40 per cent of its ori; * 2 4 r the power consumed per unit displacement 9 r ‘ ne ¥ § 150 per cent of that required for the first p T ™ condition is primarily due to cooling and j : " —— more marked in the case of plates and billet Fe blooms, which hold their heat well. The + 4 —s representative of zones in which fall test ; ; ee a large number of pieces. They are necessari — ee The first step in the determination of mot ; — SS ae 5 ‘are — 7 calculation of the load demand of the individ 1 Rs ee ee ae and the duration of each pass. The interva twe : ‘ , passes may be estimated, based on the charact ft Bey i mill and the operation of the screw down, | a by Fae [ r or transfers, where used. Where stands or g ’ thi ia J 7] operated in sequence, the slowest point det: t +i f , | maximum rate of feed. The rolling schedul s } . 0 | [7 aces on these considerations. P| [ With the above data available for perhap ; o [_ = rolling orders, load cycle curves may be prepared ¢ charting the loads of the individual passes bining them where they overlap due to steel being ‘ OG two or more passes simultaneously, In laying out su 9 | a chart, friction load is added, commonly cons , \ as a constant demand. In considering load cy ar Ss | not only normal but possible abnormal conditions mus - ’ a eae aan ie) sale ote > r 4 be taken into account. The maximum possible output [|] dicate aceasta a aed and probable average schedule must both be consider ' The drive must have capacity to handle the maximum, : | , at least oceasionally. = - ; | — bination Mill with Driv. If the load cycle is such that a flywheel is sab Siena Be ham sua the requirements may be determined from the chart. I! power conn ' In the middl a horizontal line be drawn representing maxi! rw d schedule of é uch of the motor output, the flywheel must be able to supp! F ta horsepower-seconds demand above this line. This g ; eral mode of procedure shows what effect can . Some steels are hot short and the edges fray_so that tained from flywheels of feasible dimensions. A stu 2 v6 t is necessary to take lighter drafts and more passes. of the load cycle and the flywheel possibilities det Density of steel is a factor. The cast ingot is mines the motor requirements, both as to continu : spongy and easily reduced. As rolling proceeds the and peak demands. Upon this information the n . netal becomes denser and somewhat more power is re- selection is based. juired to roll it. This action is particularly pronounced In a continuous mill the steel enters the succes : ‘s in cold rolling. The shape of the section is animportant stands in rapid sequence and remains for some tin consideration, primarily with reference to the exposed each stand. The resulting load is a sustained dema F area per unit of volume. Plates, for instance, expose gradually applied and relieved, a most favorabi , more area than ingots and cool faster. The specific power demand therefore in- —arasronce aaronag. gong ea gunige FOR ace sail n ‘reases more rapidly as rolling proceeds. © SS as : e In the initial passes, at high tempera- SSS SSS § ; tures, the specific power demand for dif- —— = =y a : ferent sections or pass shapes does not 3 Sr = on vary widely. In the later passes the a iw = ¢ an variation is much more marked. It is FEA A En = “ mad ‘haracteristic of special sections, as a ti, Seize == , . result of lateral displacement and form- eee . os ing the thin web and flanges, which cool pete =. ‘950} a ‘ rapidly and offer great resistance, that es Ss oan ; the power required for the later passes ae ee e+ f ; : s relatively high. FEF =f {1600 i ‘ The diameter of the rolls plays a t= ae ; yo gate { ce Pi ig PA part A roll of large diameter require = lagnn! 7 ; e greater pressure for a given draft be te cause of the greater projected area of contact. The increased pressure on the 7 : , roll necks increases the friction. More- oo* P ver, with a large roll there must be C more slippage between roll and steel at q : the point of entry. Large rolls are necessary for reasons of strengtl and Fig. 12. Diagram of Current Supplied to Armature of a Pla M ‘ deflection, but they require more power versing Motor Requiring Eleven Passes to Roll Open-Hearth § - mo per unit of metal displaced. In. into Plate 20% x \4 In The 8000-hp. motor runs at speeds ? Because of the many factors involved, r.p.m., with current up to 600 volts. The chart speed was ® 1922 ) shows the load curve of the continuous nd of the 10-in. skelp mill at the Mark & Tube Co. of America, when rolling 7% x 0.315 in. As there are no severe peaks n. there is no field for a flywheel, and seldom used for continuous mill jule on a continuous mill is quite simple that the required motor capacity can with relatively good accuracy. volving stands in bination type mills, the rolling schedule nd the individual pass demands will or uch manner as to load of ig. 11 shows the layout of a mill iem roughing stands followed by a guide n which the metal is hedule shows the glance how drives. several train, or in Cause a looped between and their in- loads are passes it a the pass 1 that the finishing pass is the limit The load chart, as shown, is based on a e for all the stands. If the drive ; . | J ; ws ae ey. : e0e¢«e6e @ 6 @¢-e' 8 Se. ££ @ © 64 : I \ inpu nto } I ner » ‘} l at ht) ' LT : liversity factor would have less effect n the driving units would be more of this type, having separate drives ' ng and finishing groups, it will likely be lywheel may be used to advantage for the ut is not required for the finishing ie motor driving a reversing mill in- lone in displacing the metal, superim- is the friction load of the mill and lue to acceleration and reversal. About ent of the energy demand for a pass is About two-thirds of this is regained n in stopping before reversal. The vad may best be seen from Fig. 12, a the 30-in. universal plate mill at the Steel & Tube Co. of America, while rolling iown to 0.250 x 20.5 in. The peaks due identified in most cases, as preceding each pass. the demand on the induction motor set. The effect of load demand is fairly yronounced when rolling wider slabs. oth the reversing motor and flywheel ited in a manner similar to that indi- the flywheel i1 : » ? evident, types, namely, by combining prop ‘lements and by modifying for fly- ecte 1. passes are not superimposed, r¢ Lauth plate mills being the first flywheel absorbs a consideral exampl peaks during passes ar‘ lemand. During the later pass but the demand more sustained then s ipplies about all the power llated power requirement and mo primarily as a basis of . Comparisons wit! judgment ve a bearing. THE IRON AGE 411 ther installations are of value, but allowances must be made. Some mills can handle the steel more rapidly from the furnace to and through the mill. The steel is finished hotter and requires less power. Operators differ as to drafts ually tend to demand all operating skill improves, output is expected. It is difficult to accurately the inder which a mill may be any : and passes and event- the motor will stand. As future conditions work. In due be improved and motor ‘apacity limit the output. It is there fore almost imperative that the motor selected for the duty contemplated at the To a moderate motoring. Flywheels are installed on Ilgner sets tinuous fluctuating nature. Where the duration forecast expected to time limiting factors will may eventually be liberal time of installation j istifies degree reliability also liberal running drives where the widely and the intervals ré yey serves to iT advantage well maintained, a flyv flywheel permits the use of a motor of vn 6 ’ 0 f \ ERD ; \ ee mae aes / ; _ — ° e . a ¢ ° » v . . > a 2 s . & Plate M f Fig he three-phase n r takes current iW per ! " : r multaneousl ) peak capacity Of often greater importance is the The under introduces slip losses, which The slip permissible does low motor efficiency of peak demands on utilization of a flywheel re heavy This, in turn, are greatest at heavy the power system juires slowing down loads, loads not exceed 15 per cent, due both to and difficulties in The friction important item. On the other hand, the rolling with greater speed variation 1 s losses incident to heavy flywheels are an due to better load factor at the power house may easily over balance the added mill usually a compromise. sorb all peaks above the efficiency increased The size of flywheel is losses. A flywheel large enough to ab would usually te size of the drive in average load The stem excessive in size and weight. relation to the bearing. It is drive having a + local power sy has an importan obvious that, if a flywheel is used on a of speeds, it is less effective at The selection of flywheel, motor and range he lower spec ds. control should be yased on their joint consideration, as they are closely related are of fixed or variable secondary resistors or a slip The iffords most effective util by conserving the stored peaks. Motors equipped with flywheels the wound rotor type and employ ¢ ner regulator ise of a slip regu- ization of the flywheel : ry energy lator for use only durin; y s Main drive motors may be direct connected to the mill or they may drive through rope, belt or gearing Motors direct connected to the larger mills are neces irily of slow speed, many of them operating at about 80 to 100 r.p.m. Direct connected slow speed motors are of large dimensions; their efficiency and power factor are relatively low, particularly in the case of Simplicity of drive and A 60-cycle motors. elimination of reduction gearing is their chief advantage. Motors driving a group of tandem stands may drive through gearing or combination of the two. bevel through spur gearing or a Belt drives are also employed, Bap 412 : particularly for finishing stands, as a smoother finish ' is claimed, due to elimination of gear vibration. The ; herringbone reduction gear unit is slowly gaining in sa ‘ popularity. It enables the use of high-speed motors on 4 low-speed mills. Herringbone gears are smooth in : ' operation, eliminating largely all shock and back lash and thus relieving the teeth of much punishment. They permit wide speed ratios, if desired, and have an effi- ciency of about 98 per cent. The first cost of a com- plete geared drive is generally lower than that of a slow speed direct connected equipment, but the gear drive may require more floor space. In the Lauth type plate mill, the central pinion in ¢ the housing may be made smaller than the upper and wt. | 3 ' lower gears, obtaining a slight speed reduction. In the is “Kennedy” housing the pinion is offset and larger Wi gears are used, so that a reduction of four or five