The Iron Age 1937-06-10: Vol 139 Iss 23

B ce FRITZ FRANK President VAN DEVENTER Editor Managing Editor Editor Emeritus Machinery Editor Art Baditor Metallurgical Editor Associate Editors MACMILLAN JURASCHEK Consulting Editor Washington Editors Resident District Editors CAMPBELL ROBERT BINGHAM Pittsburgh Chicago Cleveland Detroit Editorial Correspondents London, England Cincinnati FRAZAR FIDRMUC Boston Hamburg, Germany MEYER LOREN IRWIN Milwaukee San Francisco SANDERSON ASA ROUNTREE, JR. Toronto, Ontario Birmingham ALLISON Roy EDMONDS Newark, N. J. St. Louis TURNER Buffalo Editorial and Executive Offices 239 WEST 39TH NEW YORK, Owned and Published by CHILTON COMPANY (Incorporated) Chestnut and S6th Sts., Philadelphia, Pa. 239 West 39th Street, New York, N. Y. OFFICERS AND DIRECTORS MUSSELMAN, President FRITZ J. FRANK, Executive Vice-President FREDERIC STEVENS, Vice-President JOSEPH HILDRETH, GEORGE GRIFFITHS, EVERIT TERHUNE, ERNEST HASTINGS, WILLIAM A. BARBER, Treasurer JOHN BLAIR MOFFETT, Secretary JOHN VAN DEVENTER JULIAN CHASE THOMAS KANE CHARLES BAUR G. CARROLL BUZBY FAHRENDORF BAUR, General Advertising Manager DIX, Manager Reader Service Member, Audit Bureau of Circulations Member, Associated Business Papers Indexed in the Industrial Arts Index. Published every Thursday. Subscrip- tion Price: United States and Pos- sessions, Mexico, Cuba, $6.00; Can- ada, $8.50; Foreign, $12.00 year. Single copy, 25 cents. Cable Address, *“*Tronage, N. ADVERTISING STAFF Emerson Findley, 621 Union Bidg., Cleveland B. L. Herman, Chilton Bldg., Chestnut & 56th Sts., Philadelphia, Pa. H. K. Hottenstein, 802 Otis Bldg., Chicago H. E. Leonard, 239 W. 39th St., New York Peirce Lewis, 7310 Woodward Ave., Detroit C. H. Ober, 239 W. 39th St., New York W. B. Robinson, 428 Park Bidg., Pittsburgh D. C. Warren, P. O. Box 81, Hartford, Conn. JUNE 10, 1937 Politics Makes Strange Bedfellows Machine Toois Contribute Prosperity Machining Parts for World's Largest Telescope Surface Broaching High Production Industries Fundamentals Safety Steel Plants Round Dozen Unusual Handling Ideas Machine Tool Builders Contribute Mass Production Resilient Tin Plate May Pig Production Statistics Metal-Working Activity Rate Activity Capital Goods Washington News wr Just Between Two Products Advertised Index Advertisers Copyright 1937 Chilton Company (Inc.) | 32 i et- the Plant Expansion and Equipment Buying ................ 124 127 148 152 your guide all steel Structurals Channels; es, Splices, Bolts, Strip Steel, Flat re, Etc Shafting Alloy Steel Bars Here steel every shape and size any length special shape. Whatever standard and alloy grades stock for your requirements you can call Ryerson Immediate Shipment. Allied lines such with full assurance that everything possible welding rod, babbitt, boiler tubes, and fit- will done deliver the material well tings are also carried. Shears, saws and within the time specified. Ten plants stand special flame cutting equipment quickly cut ready serve you. Draw the nearest one. Joseph Ryerson Son, Inc., Chicago, Milwaukee, St. Louis, Cleveland, Detroit, Cincinnati, Buffalo, Boston, Philadelphia, Jersey City - THE IRON JUNE 10, 1937 ESTABLISHED Vol. 139, No. Politics Makes Strange Bedfellows JOHN LEWIS, head the deplores the recent killing five members the mob which marched upon the Chicago works the Re- public Steel Corp. and which refused halt when ordered constituted authorities. calls this Every other well-principled citizen this country, including the police Chi- cago and the executives the company concerned, also deplores the use force prevent anarchy. But they will not call murder. Mr. Lewis would care for real example cold blooded murder, might back, memory, the morning June 22, 1922. that morning some fifty mem- bers the Steam Shovel Men's Union, with which the United Mine Workers, headed John Lewis, were odds, were brought out the strip mine the Southern Coal Co. under flag truce. They had been promised safe conduct their homes. Before they could entrain, however, they were lined against barbed wire fence, faced with semi-circle some 500 armed union miners. Fire was opened upon the little defenseless group fifty and before the smoke had cleared away, them were dead and wounded. The victims had broken law but they had committed the unpardonable crime refusing allegiance and tribute Lewis and his United Mine Workers. that atrocious massacre, inspired mob rule, one eloquent speech con- demnation was made man well known every American. Here what said: few weeks ago, southern Illinois, atrocious massacre occurred contained our annals. Men were killed, not cleanly killed, but brutally killed, and the time which speak, there shadow conviction the murderers sight. blot this kind our escutcheon can wiped out but one manner and one manner only, and that due process law. are exist nation, must law-abiding. the law depends our society. Destroy law and the country erson reverts barbarism over night. Destroy law and will back the days slavery, rapine and pillage, when the strong oppress the weak, when interest triumphs ssible over honor. Without law, our civilization crumbles. Our government arranged such fashion that provides method whereby who compose can change it." well This condemnation mob rule was made the convention Atlantic City 1922, and none other than Franklin Roosevelt, then Assistant Secretary one. the Navy. stand 4 | “a ce 4 ¥ ‘ / | | it | | this article, from ad- dress the Machine Tool Speed Show held the General Electric Co. Cin- cinnati, May 24, Mr. Berna pays tribute the teamwork the electrical industry and suggests few points fur- ther cooperative develop- ment. return, points some fundamental services that machine tool builders can render furnishing and control and the builders machine tools themselves very effective team. The machine tool builders got head-start about 100 years but the past few years you have caught with and the coopera- tion between the two industries has been most effective. builders electric motors are particularly grateful you for the development the modern alternating-current motor, which will run for indefinite length time with very little attention. Furthermore, the devel- opment standardized motor frames has been great assistance the machine tool builder, has given between the different makes motor that has mount his machine and has eliminated good deal changing and fitting the assembly floor. Control, too, has become more compact and more convenient and now can select from the stand- 30—THE IRON AGE, June 10, 1937 equipment that will enable the electrical industries meet the lower costs entailed higher wages and shorter hours. also points out that shorter working hours and higher wages have followed naturally from the use more efficient machine tools and have not come con- sequence legislation. ards available types that are spe- cially suited each kind ma- chine tool. Still Some Worlds Conquer However, there are still some worlds left conquer. still have find better way keep- ing cutting oil out our conduits and protect our control against cast iron dust. Perhaps, too, should give some thought mak- ing our push buttons larger that man with glove can oper- ate them and more rugged that man who hits the button with pair pliers wrench will not any particular harm. There also room for improve- ment the dimension from the bottom motor feet center shaft, which dimension very great importance the machine tool builder, and which the moment only held tolerance 1/32 in. There are quite num- ber machine tool builders who would very happy cooperate with you holding that dimension closer tolerances, furnishing you with machines upon which this can readily done production basis. With due acknowledgment the service that you have rendered the machine tool industry, may also suggest that there service that can render you. That better manufacturing equipment will reduce your costs, make possible for you work closer tolerances, enable you pay high- wages and work shorter hours. There now, and there has always been only just that one way accomplish these desirable things whether build motors mat- tresses. Higher Wages and Shorter Hours Through Increased Efficiency There tendency among hu- man beings, and has not been distinctive any one group even any one nation, accom- plish reform legislation. agree that the 8-hr. day and the elimination child labor are de- sirable ends, why not simply enact laws that will make these things obligatory? takes long educate the majority and many them are indifferent even these laudable causes. But when our legislation runs counter the fundamental laws nature, be- comes dead letter, had ample opportunity find out when tried enforce prohibition. are now trying find short cuts that will permit higher wages and shorter hours without increas- ing the output for each worker increasing the efficiency our plants, improving our equip- 4 : q | at | | ° ° | General Manager, National Machine Tool Builders’ Association, Cleveland TELL BERNA ° ment, but this method runs counter all human experience and will probably fail. About hundred years ago the development the reaper, and the gradual opening good farm land, gave the American farmer surplus crops which could sell for cash, and made possible for him begin buy those things which had been making for himself, laboriously, the farm. Simultaneously the demand for machine tools developed and the industry became increasing im- portance the demand for ma- chinery increased the industrial centers the country. Hanging the office the Brown Sharpe Mfg. Co., Providence, I., schedule working hours, which was written Mr. Lucien Sharpe, the founder Brown Sharpe, when was employed the Providence Machine company’s plant the winter 1847-48. During most the months work began sunrise, but May, June and July the worker was allowed idle bed until the atrociously late hour 4:55 a.m. stopped for breakfast 6:30 and went back work ten minutes after seven and the day continued until 6:45 the evening, with min- utes off for lunch the middle the day. The total hours per week varied somewhat the time the sunrise changed the dif- ferent parts the year, but the minimum hours per week were the maximum 77.4. Shorter Work Week Not Result Legislation That sharp contrast with present conditions. are prac- ° tically standardized 10-hour week. The important thing realize that this change has not come about legislation. 1899, long before the 8-hour day was legally required, the average hours per week this country were 55. Here then substantial reduc- tion from the day Lucien Sharpe. 1920 the average hours per week this country had be- come hours, 1930 the average was hours and today prac- tically hours week. The im- portant point that this improve- ment was effected, not legisla- tion, but giving the worker better equipment which made economically possible for him earn living wage while working shorter hours. show that this change ran parallel with another equally important change and that was the real value the wages paid the worker. These again not legislative fiat, but the increased earning power the worker, due the better equip- ment which gave him, or, you please, because the increase horse-power per worker during these years. healthy development toward lower hours and higher wages, have the arbitrary restriction output union regulations which fa- miliar all the building trades. These trades wait for improved methods, improved materials, and better equipment make economically possible re- duce working hours and increase wages. They reduced them arbi- trarily and the net result has been choke the building industry and force live obsolete anti- quated houses because the cost new construction entirely out line with the development the country other fields. Machine Tools Contribute Higher Living Standards The machine tool has also served the nation making possible low- costs and that, turn, means increased markets and the conse- quent enrichment human life making possible for have our homes everyday neces- sities the things that our grand- fathers would luxuries, would not have had available any price. are little inclined over- look the fact that the modern ma- chine tool does not require high degree skill the part the individual workman. Accuracy built into the machine and the measuring instruments which the worker uses check the product the machine. hundred years ago worker with little training was helpless, because everything had done hand and even the products the elementary machine tools that day had corrected skilled artisans who did this work hand. This means that can open our factory doors these semi- skilled men and some who have practically skill all and en- able them earn high wages the operation machines. The (CONTINUED PAGE 96) THE IRON AGE, June a) | % | ° | | | | i} it | + \ | | > | lachining and Assembling arts for Largest Telescope tube member, consisting main central section, mirror cell the lower end, and prime focus cage GEORGE PASSMORE the upper end. Manufacturing Superintendent, West- inghouse Electric Mfg. Co., South telescope mounting here referred that for the optical system the 200-in. telescope erect- Mt. Palomar, Cal. Complete, the telescope will weigh more than the two main members comprising the mounting, supporting cradle yoke, the former dealt with particular this article. This tube member made several sub-assemblies the cage, top ring, five central FABRICATING and machining structure large this mount- ing for the 200-in. tele- scope order manufacture, handle, transport, and erect this structure, was necessary build sec- 32—THE IRON AGE, June 10, 1937 Philadelphia Works panels, bottom ring and mirror cell—bolted together and connected means struts the form A-frames. measures ft. length, and weighs more than 150,000 Obviously, structure hav- six-story building, and sup- porting structure the same length with width equal building, presents unusual manufacturing problems. tions, which are bolted together form the whole structure. Each unit built welding and bolts are used except the joints connecting the units. The prime focus cage, which attached the top the tube and contains the prime focus equip- ° ment and observers’ house, one-piece fabricated and welded construction, ft. diameter and 12-ft. high, weighing 23,200 Ib. when finished. consists bottom ring box construction joined top ring I-section eight box section columns and cross braced with 6-in. H-beams. Prime Focus Cage Held Close Tolerances Fabrication was held very close tolerances, especially the spacing pieces 3-in. pipe the bottom ring, bolt circles ft. in. and ft. in. respectively. These pipes serve containers pockets for exten- sion clamp the cage the top ring the tube the outer bolt circle, and also for eight jack screws for breaking the joint when removing the cage. They were placed position for welding means jig sweep covering one-eighth the circle and swing- ing about the center the layout. The lower surface the bottom ring the cage has two annular bearing surfaces, wide, j | | lar de, which were machined boring mill, shown Fig. The inner bearing surface contains accurately machined keyway wide, which had fit ex- actly sectional key fitted into similar keyway cut the top ring the tube. Since the bolt holes had drilled from the finished surfaces and inside the above mentioned pipe pockets, was necessary obtain starting point for centering the cage the mill for machining the faces and the keyway, working back from average position these pock- ets the outer bolt circle. This was done drilling eight exploratory holes upwards from the blind ends eight alternate pock- ets with the use centering de- vice the pipes. These drilled holes were also used later basis for the drilling layout. Cage Bolt Holes Accurately Spaced The cage, when mounted the telescope tube, will support 6-ft. diameter observers’ house the center, connected four knife-edge diaphragm plates. The design the cage called for its orientation any one four positions the tube, varying steps 22% deg. The bolt holes and holes match the guide studs projecting from the top ring the tubes were, therefore, required accurately spaced. All this drilling was done while the cage was still the boring mill, using 10-ft. radial drill press set 4-ft. table alongside the mill, the bottom the cage, be- tween the annular faces, were welded pads which the holes matching the guide studs were drilled 20-ft. 5-in. pitch circle. These holes were indexed counting the number revo- lutions the driving motor for one-sixteenth revolution the mill. Accurate readings small frac- tions turn were obtained means fixed pointer against steel tape the circumference reading 1/16 in. this tape corresponded about 0.002 in. displacement the pitch circle. One-half inch holes were drilled first, and pins fitted into them were used for checking the pitch with inside micrometer from pin pin. further check was made measuring from the pins point the drill press arm. this way, the pitch the holes was held accurately within few thousandths inch. jig centered the above pins was then clamped the ring, space the holes the outer and inner bolt circles. the same time, the %-in. holes were enlarged These holes were en- larged later, during the assembling shell reamer centered temporary studs the top ring the tube. Machining Top Ring The top ring the tube box construction, 22-ft. diameter, having pairs gusset plates the quarter points for attachment the tube struts. Its upper face machined with two bearing sur- faces and keyway match those the cage. Each the machined faces has tapped holes for studs. the bearing surfaces there are this case only four pads with tapped holes for the guide studs. All this drilling and tapping was completed the mill manner similar the cage. the completed 200-in. telescope will appear after installation Mt. Palomar, Cal. cage the tube after its erection the shop, the top ring the tube was set parallel, with four temporary special studs the guide stud holes. The cage was then set the ring the first the four marked positions, and four the matching holes enlarged with shell reamer guided the temporary studs. The posi- tion the tapped holes for the studs the ring was checked observation through the holes the bottom the pipe pockets the cage. The cage was next lifted and rotated deg. for each the other three posi- tions, and the other three groups four holes for the guide studs reamed out the same The cage was then removed and the proper guide studs down studs fitted. Finally, was tested all the four positions make sure that all the studs were clear the holes the cage. Operations Bottom Ring Tube Member The bottom ring the tube which the mirror cell attached with eight knee also j mee ° ° ° box construction, ft. di- ameter, with conical outer shell, having pairs gusset plates the quarter points for attachment the tube struts. These gusset plates form the sides four rec- tangular boxes with machined pads the top. The inside diameter the ring ft. in., leaving surface 14-in. wide the inner side these boxes, forming con- tinuation the top the ring. 2—Machining pads the mirror cell ring, reversing the 32-ft. boring mill like planer and em- ploying clapper box for the tool. 34—THE IRON AGE, June 10, 1937 this surface are machined pads in., each with bored and reamed hole sur- tapped holes. These bored holes are for locgting the housings for the driving units for the mirror shutters safety covers, and were required accurately spaced. Outside this ring pads are two groups pads for two driving these pads are placed motors. joint prime focus cage 32- ft. boring mill. The radial drill the table beside the mill for drilling bolt holes the lower ring the prime focus cage. between the rectangular boxes, was not possible machine them the ordinary way. Consequently, they were finished individually reversing the mill like using clapper box for the tool. See Fig. The bottom this ring has eight finished pads for the mirror cell brackets. These also have three bored holes for locating blocks against which the cell brackets are | | | | | attachment the cross-rail planer for machining the flange joint the These hinge members are 20!/2 ft. wide. adjusted set-screws, for alin- ing the optical axis the mirror. The east, west and north tube panels are box construction, phragms. The south panel the form two triangular trusses separated long slot extending from the top the bottom ring the tube. The panels form frame ft. square the center the tube. They are connected the corners the square flanges arranged deg. the planes the panels. These flanges are welded the end plates where they converge form deg. Vee. This construction provides certain degree flexibility the connections and thus prevents the locking any stresses the structures. Flange Machining Required Special Equipment The machining these flanges for special equipment since planer was available finish pieces wide. This was done means milling attachment mounted the cross-rail 14-ft. planer, with feed along the 4—Tube panels being set and accurately alined, prepara- tory drilling and fitting bolts the panel hinge flanges. rail driven separate motor and worm gear reducer. The mill- ing fixture itself, Fig. has vertical spindle driven motor and worm gearing, with deg. conical cutter with spiral cutting edges. The two ends each the east, west and north panels were ma- chined with this attachment, the planer table being traversed bring the flanges into position next the cutter. Absolute parallelism the flanges was insured this manner. The angles the faces were checked with bar. Small machining lugs each end all the flanges were milled off vertically give exact overall length the panel, where their faces intersected the 45-deg. flanges the center line the width the panel. The flanges the two halves the south panel were machined the usual way the planer, since these pieces were only half the dimension the other panels. How the Tube Was Assembled assembling the tube, the east, west and north panels were THE IRON AGE, June 10, 1937—35 set parallels the floor plates accurate layout. The machining lugs the end flanges were used advantage drop- ping plumb lines from them the corners the layout. The three panels were then clamped together j distance from the center line the tube dropping plumb lines the layout. This depended the accuracy with which the con- necting flanges were planed with respect the ends the trusses. After thorough check-up, the 5—For machining the panel bores for the bearing gimbals boring bar set three pedestals was employed. was ft.; bore diameters are the flanges and braced with pipe jacks the floor. The inter- sections the machining lugs with the flanges the south ends the east and west panels were then checked for plumbness with transit. The upper halves the south panel were next set and ad- justed with members clamped between ma- chined pads the webs the beams forming the sides the slot. The upper ends the trusses had set exactly the right 36—THE IRON AGE, June 1937 The maximum driving length the bar and in. respectively. connecting flanges the panels were drilled and reamed for 1-in. turned bolts each. See Fig. Four 16-in. cast iron flanged pipes, capped with heavy screw jacks, were next set the corners the square and work- ing platform was built around the assembly. The top ring the tube was then raised and set the jacks the correct height, with the gusset plates the south side the ring slipping down over the ends the trusses the south panel. The next step was assemble the 21-in. I-beam struts joining the top ring the ends the panels, inserting them between the mating gusset plates each end and clamping them place. The alinement the top ring was then rechecked, after which all the strut connections were drilled and reamed for 1-in. fitted bolts. Four 34-in. taper pins also were fitted each beam con- nection facilitate erection the field. The jacks under the top ring were then backed off. Boring Panel Bores for Gimbals The weight the telescope tube carried the flexible gimbals mounted the east west panels. These gimbals turn are bolted hollow spindles rotating ball bearings which are mounted the center sections the tubular yoke girders. The center lines the panel bores for the gimbals were required the face the top ring. For this work, 10-in. boring bar hav- ing screw feed the traveling head was set three pedestals, one the center the tube and one outside each panel, with worm gear belt driven from motor the floor. See Fig. The boring bar was checked for parallelism with the top ring means what was virtually hook gage. The diameters these bores are and in. respectively. The maximum driving length the bar was about ft. Because the tendency the bar sag under its own weight weight the boring head, was necessary set lathe steadyrest next the latter. Likewise, order prevent chatter due the torsional deflection bar this length, only light cuts could taken. Due its total length, was not practical assemble the entire tube vertical position. Conse- quently, after the finish bored, the structure was braced with struts and laid down its side. Then the lower ring mirror holder was set position and assembled panels 21-in. beams, using the same methods assembling the top ring. All mating pieces were plainly marked and tapered dowels fitted facilitate erection the field. Surface High-Production Industries HAPE, size and the quantity production are generally leading factors selecting the type machine used for finishing part the broaching method, was stated joint paper* Sol Einstein and Romaine, the Cincinnati Milling Machine Co. Various types and sizes surface broaching ma- chines are the market, compris- ing either continuous machines the so-called ram type which either tool work stationary, with relative movement between them straight path. Advantages surface broach- ing are: (1) Exceptionally high produc- tion the machining flat irregular surfaces parts. (2) Roughing and finishing size one operation. (3) Large production before re- sharpening. (4) High degree finish. (5) Close tolerances maintained continuously. (6) Due long tool life and exceptionally high production, low cost per piece. The automotive industry offers the greatest possibilities surface broaching. Among parts capable being machined are top, bot- tom, manifold face, water jacket, and flywheel housing cylinder blocks; cylinder heads; crankshaft bearings; connecting rods and caps; shock-absorber arms; steer- ing knuckles; *Abstract paper presented be- fore the semi-annual meeting De- troit the American Mechanical Engineers, May 17-21. rear-axle shaft ends and many others. Limiting factors broaching are: Work strong enough withstand broach- ing stresses set up; must have the ability supported firmly; and cannot have any obstruction Today, practically all connecting rods and caps are finished broaching. previous equipments, the parting face and the half bore were machined simultaneously, us- ing flat broaches which interlocked with circular broach, but recent set-up the broaches are de- signed machine the rod progres- sively, the half bore first and then the parting face. The tools for both portions the operation were de- signed that they took the full power the machine, with the net result that the half-round portion was broached tool which was about per cent long would have been required the other method. addition, the elimina- tion the interlock types cheaper manufacture. Cylinder-Block Broaching Machine Outstanding surface-broaching operations are performed cylin- der blocks. secure basic data, from which recommendations for broaching equipment made, large experimental ma- chine that was powerful and large enough broach top bottom, end sides any straight-line cylinder block any passenger- car engine then existence was built. Different designs cylinder block were broached experimental- ly, and, result, the following factors must determined before proper machines, fixtures, and tools for this particular job could de- signed: (1) Total pressure the casting will stand without breakage. (2) Method supporting the casting against the broaching pres- sure. not exceed the strength limits the casting. (4) Arrangement the tools remove the metal minimum time and still produce satisfactory de- gree accuracy and finish. (5) Determination chip size removed each tool without causing excessive flaking-off breaking-back the edge the casting points where the tools leave the work the end the cut. With the equipment for broach- ing the top surface cylinder blocks production obtained from machine betweer. and cylin- der blocks per hr. Since the ma- chines are actual practical use, the total labor cost per cylinder block was computed based hourly rate, and the tool cost per piece $0.045. These figures indicate considerable sav- ing labor and tool costs over methods previously employed. result extensive experi- ments, the broaching tools used are the inserted-blade type. They have been carefully designed re- move metal depth approxi- mately 3/16 in. the minimum time and still produce finished pieces with unusually close toler- ances for accuracy and flatness surface and high degree fin- THE IRON AGE, June 10, 1937—37 i & | | j a ag ; Pe ish. The use tungsten-carbide finishing tools important fac- tor obtaining these results. Design Surface-Broaching Tools Since surface broaching rela- tively new art, design the tools based the experience gathered from previous installations and ex- periments practical applications. Two major items, size and shape, control this design. Naturally, the former determined dimensions the piece broached, number teeth, their pitch, percentage teeth for roughing and finishing, rake and clearance angles, and whether the teeth spiral, staggered. The latter definitely governed, greater lesser degree, the part broached. The tooth must designed have sufficient strength and also provide proper clearance and rake angles. broach, the forward teeth remove the metal, and the last teeth prepare the finished sur- face. Thus, the front forward teeth can designed rugged manner with relatively small rake angle bear the brunt the work removing metal, while the last teeth can designed with higher rake angle produce the smoothest possible The clearance angle tools for broaching cast iron can vary from deg. and have very little influence upon the force required take any reasonable depth cut. any other cutting tool, the factors governing the clearance angle broaching tools are: the clearance must great enough prevent the tool from dragging the work; second, larger clear- ance angle than necessary un- desirable from the standpoint economic tool life. Tools the cylinder-block jobs have clear- ance angle deg. and give satis- factory results. Clearance angles tools for broaching various steels are somewhat similar those for cast iron. Clearance angles deg. have been employed good advantage forgings SAE 1035 and 1040 steels. For nickel- chromium steel, similar SAE 3115, clearance angle deg. was found best, since this metal has tendency tear and fuse the tool, thus spoiling the finish. The undercut rake angle can vary from deg. cast iron and effects the cutting force and the finish obtained. Broaching ex- periments show that rake angle between and deg. produces very satisfactory results cast iron with good finishes and com- paratively long tool life. Practical- the same results are obtained when broaching steels malleable iron. For steel forgings, rake an- gles deg. are used. For stain- less steels, rake angles between and deg. will improve the finish, but tool life naturally less than when angle deg. used. Side rake shear angles im- prove the finish cut. For cast iron, side-rake angles deg. are recommended. For steels, this angle can vary deg. Side- rake angles between and deg. are desirable steel forgings, they produce fine finish and give satisfactory tool-life. ° ° duplex ing the half bore and parting face automobile engine connecting rod. Chip Clearance tool governed three factors: First, the chip per tooth; second, whether the material being broached has tendency tear whether has even chip flow; third, the nature the chip itself; that is, the chip tends curl curls one piece. Experience has indicated that radius the bot- tom the tooth best for aiding the chip curl, particularly for broaching steel. Chip breakers are desirable material that tough and chips and particu- larly when heavy chip per tooth formed. Chip breakers should not used the finish section broach those teeth imme- diately preceding it, since they tend produce grooves, which the fin- ish teeth not remove. Generally speaking, they are not necessary broaches for cast iron except heavy roughing cuts. Chip size per tooth broach varies with the stages metal re- moving. the roughing section, the chip should preferably short and thick, thus minimizing break- out the end the cut. The fin- ish section broach naturally has remove the rough marks and lines, produce smooth surface, and, the same time, give the piece its proper size. steels, chip per tooth ranging from 0.005 0.010 in. can used the roughing section, 0.005 in. the semifinishing and from 0.0005 0.002 in. the finishing section. Work-Holding Fixtures Forces set broaching are two definite directions, one line with, and the other normal to, the path the broach, and these sometimes vary considerably magnitude but never direction. The most important point watched broaching-fixture design stabilization the workpiece the fixture avoid vibration and springing while the cut Low Unit Time and Tool Costs Low unit-time surface broach- ing due, part, the speed which the cutter passes over the work, which from times faster than the rate milling. The second important advantage the broaching method lies the low tool cost per finished piece usually obtained. comparison with milling, first cost broaching | | | | \ | tools rather high. Milling cut- ters the arbor may compared with broach inserts, and, generally speaking, the cost these inserts higher than that milling cut- ters. However, when comparing the total actual cost the tools used high production, the broaching tools show lower total cost. This due the extremely long life between grindings, which usually days with broaching cut- ters, compared hours for the milling cutters. Long cutter life due num- ber factors, among which rigid- ity the average setup and low cutting speed may mentioned. Milling cutters normally run between and more feet per min., while broaching tools pass through the work approxi- mately f.p.m. One the chief factors favoring the broach the fact that tooth takes chip constant thickness; does not have build that chip from zero the maximum thickness the ordi- nary milling cutter does. The mill- ing cutter has sharpened with fairly high clearance angle and has backed off maintain rather small land, with the result that heat conduction from the mill- ing cutter the other hand, the broaching tool not be- ing forced into the work but splits off chip ahead it, with the result that can operated with much smaller clearance angle. necessity exists for any back- ing back-off angle nar- row land, that the heat conduc- tion better. broaching, abra- sion due rubbing-over the work before starting chip eliminated, and lower clearance angles can THe work-holding fixtures this special horizontal broaching ma- chine for 6-cylinder engine head permit the top bosses and water outlet face machined one piece and the cylinder block joint face the other. The work loaded, removed and interchanged without stopping the machine. ° ° ° employed, resulting stronger tooth and less inherent wear the tool. Easier application coolant important factor broaching. broaching tool, coolant actu- ally flows between the tooth spaces under slight pressure, acting separate the chip from the tool. Broaching tools have long life because the roughing teeth remove the metal and the finishing teeth not encounter any scale and re- move only the minimum stock. Depth Stock Removed Important Stock removal varies from few in. the maximum. almost every case where surface broaching has been applied, the stock re- moved from forging from surface previously machined, from castings that were made mechanical foundries high-pro- duction methods where much varia- tion dimensions not permitted. Only high-production industries rough parts come through with average stock-removal in. less. Other industries cannot afford spend the money pat- tern and foundry equipment re- quired hold castings certain close limits. Stock removal has important influence broaching. piece that normally requires in. long, and has in. excess stock comes through with total approximately in. stock removed, doubling the broach length necessary, which doubles the length travel and time re- quired produce the piece. Slow- ing down the speed does not re- move excess material. course, two cuts could taken the equipment were designed that the first in. could removed one stroke and then adjustment made remove the second in., but this not usually done high-production setups. The only way play safe design the broaching tools for the maximum depth stock that will ever encountered. This means, course, that the time per piece will the same for pieces having less excess stock for those with the maximum stock. From the fore- going, any increase the use surface-broaching machines would appear depend more less upon the development forging and foundry practice point where variations the depth stock removed can held within close limits the minimum. The rather high cost tool equipment militates against broach- ing, especially the low-produc- tion industries. Another point considered that, even high production, many pieces have shape which precludes using the broach. broach surface any part, this surface must lo- cated the work that broach passed over it. Sometimes, meeting this condition not possible, which eliminates the broach. THE IRON AGE, June 10, 1937—39 | | Fundamentals Safety and Abstract Discussion Mr. Burnett’s Paper GEORGE FONDA Weirton Steel Co. HEN the facts are ably reviewed Mr. Burnett, difficult believe that much has been accomplished such relatively short time. Prior 1910 was more less accepted fact that there would from three four fatal accidents per 1000 men per year the steel plants the country. But between 1911 and 1913 movement was started group enlightened “pioneers” the steel industry, which culminated the founding the National Safety Council and the organized drive against industrial accidents was on. know that while wage earners the steel industry were increasing from approximately 278,000 1913 some 425,000 1923, during that same ten-year period, the frequency fatal accidents was reduced better than per cent rate less than one fatality per 1000 workers per year. fact there every indication that this low rate was reached 1920 and since that time has not only been maintained but consistently reduced. the steel industry whole, there has been yearly average approximately 380,000 wage earners the payrolls for the 17-year period 1920 1936. the rate fatalities indicated prior 1913 there would have been possible 1300 more accidental deaths recorded, the average, for each the years from 1920 1936. How well the steel industry has carried its campaign against industrial accidents proven the fact that, through intelligent supervision and efficient management, unbelievable reductions have been made disabling and fatal accidents. maintaining the low frequency rate for fatal accidents, conservative estimate indicates that over 18,700 lives have been saved the steel industry during the past years. There just one other thought would like bring out. Recent events have served create much confusion the minds the workers the steel industry which certain have detrimental effect upon accident prevention activities the industry. Dating back some years, selected groups workers were organized into safety committees for the purpose educating fellow employees the elimination unnecessary accidents. Without this cooperation the workers themselves, the impressive record which has been made the steel industry would not have been possible. Next year the National Safety Council, founded “Steel Pioneers,” will celebrate its 25th anniversary and the iron and steel industry will receive the plaudits the nation for its leadership and record accomplishment. But the industry cannot rest content with our accomplishments the past; must on. The American Iron and Steel Institute can greater work than answer this challenge humanity. 40—THE IRON AGE, June 1937 BURNETT Vice-President, Steel Corp. THE American safety definitely started more than years ego. Massachu- setts and New York enacted laws requiring the safeguarding ma- chinery and safety inspection factories 1887. Before 1900 number other states had passed similar legislation. general, however, during those early years efforts toward safety and accident prevention scattered and there seems have been very little appreciation the em- ployer’s responsibility prevent accidents even the feasibility accident prevention, and both the frequency and severity in- dustrial accidents were extremely high. The real, concerted safety move- ment may said have begun about 1907, stimulated severe criticism the press that time, the erality courts granting com- pensation injured workmen, and the safety campaign launched the United States Steel Corp. and number other leading corporations. April, 1908, the Central Com- mittee Safety was formed the Steel Corp. and soon became important clearing house for all its many units. reported that the end the first two years activity the committee approximately 6000 safety recom- Abstract paper presented before the general meeting the American Iron and Steel Institute, New York May 27. | 4 | = ' | | : | | | | | ° ° ° | | | | | | | | | | ; i é 4 | | | | | | | mendations hed been made, which per cent were adopted. 1907 the American Institute Social started the American Museum Safety New York City. The museum was incorporated 1911 and began once aggressive educational campaign safety. Perhaps the first technical as- sociation appoint safety com- mittee was the Association Iron and Steel Electrical Engineers, formed 1907. was the first large organiza- tion realize the necessity for the formation national or- ganization “for the promotion safety human life,” and its convention Milwaukee, held October, 1912, conducted the first Co-Operative Safety Con- gress and appointed committee composed industrial leaders and Federal and State officials or- ganize and create permanent body devoted the promotion safety human life the indus- tries the United States.” The result this resolution was the formation the National Sefety Council, which has become the largest and safety organization the world. has extended its influence and assistance far beyond the indus- trial field, and today composed tically every form human en- deavor. The National Safety Council was not only iounded and organ- ized but fostered the iron and steel industry, until became well and firmly established. The Metals Section the Council among the larg- est and most active today and some its important contributions the industry have been the com- dent Prevention Steel Abstract Discussion Mr. Burnett’s Paper BLANK Jones Laughlin Steel Corp. MIGHT give few illustrations further proof some the timely statements made Mr. Burnett and elaborate little some phases the work which have been hobbies mine for number years. Little could have been accomplished the beginning without mechanical safeguarding, course, but the chief value this today demonstrate that employers are interested accident prevention and willing their part making the plant safe physically possible. Thousands dollars have been spent engineering and mechanical revision and safe- guarding, say nothing protective equipment. Mr. Burnett mentioned checking new plans for safety. illustration let say that cost $40,000 incorporate into our new strip mill plans the feature safe clearance between the end tracks overhead electric traveling cranes and building columns. But with all these modern safety features building and machine guarding, operations cannot made mechanically foolproof, and necessary carry educational cam- paign enlist the active support and cooperation every individual the plant. recent innovation safety bulletins the new jumbo poster distributed the National Safety Council. This poster ft. size and pro- duced color. The slogans are short and the point, can read glance, and stand out conspicuously plant entrances and other advan- tageous locations. Too much attention cannot paid the foreman. just important today ever industrial organization, and his careful selection and training are paramount maximum results are obtained. Another activity which has bearing safety first-aid training, for while this work primarily train employees caring for injured work- men, necessity calls attention hazards, and emphasizes the importance prevention. Many companies conduct first-aid contests between depart- ments and plants order maintain interest this worth-while endeavor. Mr. Burnett has mentioned that worker safer modern steel plant than the public highway even his own home. This has been sub- stantiated our experience checking our group insurance records through which have record practically all deaths our organization. one period nearly months one our plants, during which period there was not single industrial fatality, employees met death through accidents outside the plant. During another period found that seven had been fatally injured outside the plant, while there were fatalities inside. THE IRON AGE, June 10, | 4 | 4 | | | i - j | | a i i pilation safe practice phlets; the furnishing reliable accident statistics; the promotion and formation safety codes, and the establishment and maintenance councils. The safety movement steel industry was officially recog- nized when the American and Steel Institute included two addresses safety and welfare the program for its general meeting May, 1912. The papers were published the 1912 year book the institute. Before compensation for acci- dents industry had been inau- gurated the United States, the Bureau Labor Statistics had been making annual study (be- gun 1910) accidents and ac- cident prevention the iron and steel industry. 1926 the bureau began the collection compre- hensive scale industrial acci- dents selected manufacturing industries. For this manuscript, the author has drawn freely from the litera- ture both the bureau and the council for information tistics, and even though every instance credit may not specif- ically acknowledged, those familiar with such literature will readily recognize the passages. thus seen that more than years ago the iron and steel industry declared war upon indus- trial accidents. that time the industry was classed extra hazardous and the public, with good reason, considered the job the steel worker dangerous occupation. the case most wars, our war acci- dents began mere skirmish conducted few faithful pio- neers who realized that something must done about the many in- juries suffered steel workers. The mass attacks upon the com- mon enemy were come much later, when was fully realized that order win the battle would necessary enlist the active services every man the industry. Safety began purely hu- manitarian measure, save lives and limbs, and prevent pain, sorrow and suffering. There was not the start much thought saving money improving effi- ciency. The enactment work- men’s compensation laws, how- ever, from 1911 onward, which acted throw large part the 42—THE IRON AGE, June 10, 1937 financial costs accidents directly upon the employers, brought the matters efficiency and economy the front and gave another strong stimulus the further de- velopment safety and accident prevention. Early Accident Experience Although accurate statistics are lacking the number, kind and severity accidents the iron and steel industry long more years ago, known that there are now only about one-ninth many accidents million man-hours worked there were years ago, and the number days lost per year such acci- dents has decreased only one- third many. ports that 1907 there were 82.06 accidents the steel indus- try for every 1,000,000 man-hours worked, and 6.9 days working time was being lost injured em- ployees for every 1000 man-hours worked. Since that year the gen- eral trend both frequency and severity has been sharply down- ward, and only occasional years has turned slightly upward. 1935, the last year for which com- plete records are available, the frequency rate was only 8.86, only 10.8 per cent the rate 1907, and the severity rate 1935 was only 2.04, only 29.5 per cent the rate 1907. the everlasting credit the leaders the industry and indicative their wisdom and common sense that they have gladly assumed their responsibility and have devoted their time and en- ergy safety work, and have spent millions dollars mak- ing their plants safe and com- fortable engineering skill and ability can make them. From the inception the cam- and kept its place lead- ership safety and has served inspiration and example, not only other industries but also legislators and officials who make our laws. Many the laws the statute books our federal and state governments, with ref- erence safety, sanitation and welfare, are actual declarations policies which were first adopted and practiced the steel industry. 1935, the latest year for which the National Safety Council has published complete data, only council had proportionately fewer accidents than the steel industry. these six, only the cement in- dustry closely comparable with steel manufacturing heavy prod- ucts mass production The five others were the tobacco, laundry, rubber, printing and tex- tile indu