The Iron Age 1922-08-03: Vol 110 Iss 5

THE IRON 4 New York, August 3, 1922 ABLISHED 1855 Problems in Localized Case Hardening VCL. 110, No. 5 O Low Carbon Machine Steel Used—After Carburization and Annealing. Material to Be Removed Machinable and Not Distorted in Subsequent Hardening BY R. A. MILLHOLLAND N the problem of localized case hardening the manu- facturer often confronts incurred experimental expense and defective results. losses through Localized case hardening, as the writer uses the n, is the production of case hardened parts that ive certain areas which from necessity or for reasons f subsequent machining operations must be kept in a machinable state. A characteristic example taken from the writer’s experience is to be found in the manufac- This part is a member of a screw machine which fits on the nd of a screw machine spindle. Into it is forced the ollet nose employed to grip the stock. It is readily seen that this hood must be accurate or the collet will not chuck the stock concentrically. For many obvious reasons this part must be hardened and ground to ob- tain the best results. The method that would be usually employed would be to finish the hood with allowance for the usual grind- ng and chasing the thread before hardening. This method, however, is poor practice and leads to many difficulties. The principal ones are: Distortion of the thread lead and the added expense of lapping threads that shrink in hardening. ture of master collet hoods for screw machines. One of the Problems Stated Since it was predetermined that the hoods were to be hardened, it was decided that the hoods be made of low carbon steel and afterward case hardened to a depth of about 3/32 in. The case-hardening method was decided upon because it was cheaper to machine the hood from a soft steel and also because localized case hardening could be employed. In making the first hoods the usual mistake was made; that is, the hoods were machined, allowing stock for grinding, and the threads were chased before hard- ening. Right there the trouble started, for after the hoods were hardened and ground to size, it was found that some of the threads had shrunk and considerable expense was experienced in lapping in order to fit the ge. Other threads expanded and the parts were a il loss. In still another case the lead of the thread hanged so badly that lapping was impractical and nese pieces were also a loss. It became very evident it the cost of manufacture and, ipled with the excess expense, it was found that no hoods would chuck a test bar alike even when the ‘me collet was employed. This lack of uniformity was ‘arming, and after considerable experimental expense trouble was found in the distortion of the threads. Once having established the cause, the remedy was next step. Strange as it may seem, this was not Ra was excessive, Several methods were avail- able; one was to quench the nose of the hood and leave aS easy as It now appears. the thread soft, but this was discarded, as it gave un- satisfactory results. Another method was to use clay packing or copper plate on the thread diameter and not chase the thread until after hardening; but in spite of all that could be done hard spots showed up that made the threading operation too expensive, and even with the utmost care the hard spots affected the lead to such an extent that fault showed up when the test bar was chucked and indicated. Finally the solu- tion to the difficulty came by the process of elimination, and the following method was employed with splendid results and with a minimum manufacturing expense: Method Employed The hoods were machined in the regular way except that on the threaded diameter there was left % in. of stock and on the back face ‘4 in. of stock and the threading operation was omitted until after the carbu- rizing operation. The hoods then sent to the heat-treat department and the proper penetration of carbon was given with no attention being paid to local- izing the carbon. were After the hoods were properly car- burized they were allowed to cool in the pots and there- fore were in the annealed state and quite machinable. In this soft state the hoods went back to the machine shop, and the carburized area on the thread diameter and the back face of the hood were turned off. This turning operation removed all the high carbon steel on the thread area, and when the hoods were subsequently heated and quenched the thread area remained soft and quite machinable, while the remainder of the hood was as hard as could be desired. The grinding of the hoods was purely a mechan- ical operation, the accuracy of which was controlled to a nice point. After the grinding operations, the hoods chucked, indicated for concentricity, and the threads were chased in the soft machine steel without difficulty. This because it is a well- known fact that low machine steel does no. harden perceptibly af the temperature which hardens the outer case of a high carbon content. Needless to sav the result was a very uniform product with unsur- passed accuracy and interchangeability. were was possible carbon How a Second Problem Was Met Another case that came to the writer’s attention afterward was handled on the same plan and gave per- fect results with no experimental expense. A large fixture required a number of long parallel strips that had to be hardened and ground. These strips were lo- 265 . \ : © & 4a + . = + SS ~ 2 : rik . 1 i : @ ; } ‘ . . . i “? ~ ao . ‘ ‘ . 266 THE IRON cated with dowel pins and held in place with filister head screws, the threads being in the strips. In the light of past experience it was readily seen that if the strips were drilled and tapped before hard- ening that distortion of the strips in hardening would throw the alinement of the hole in the strips out of relation to those in the body of the fixture. With this in mind the tool room was ordered to make the strips from low carbon machine steel of about 0.10 to 0.20 per cent carbon and to send them to the heat-treating department before drilling and tapping in place. In- structions to the heat-treating department were that the strips were to be carburized to the proper depth and allowed to cool in the pots. This left them in the soft state, and upon being returned to the tool room, the carburized area on the bottom side of each strip was machined off and plainly marked to that effect. Stainless Steel in Mining A paper on “Stainless Steels” was presented at the summer meeting of the Institution of Mining En- gineers at Sheffield, England, by Dr. W. H. Hatfield, head of the Brown-Firth Research Laboratories. The London /ronmonger gives this summary: The author asserted that the mining industry has not taken the best advantage of the development in steel metallurgy during the last 40 years. The indus- try is based on mild steel, and from a commonsense point of view probably it is right. But in the develop- ment of armaments, aircraft, automobiles and many other present day applications of steel, there has arisen a series of steels having much greater strength coupled with a considerable and sufficient ductility, which might be applied in different directions in the mining industry. There are many items which could economically be manufactured of stainless steel, for instance, boiler fit- tings, pump rods, pump cylinder liners, valve parts for steam, water or air, impeller blades, rotary pumps, fan blades, pins for lifting apparatus, hooks, shackles and pins for coal conveyers, weighing machine parts and gauze for safety lamps. Wire ropes made from tainless steel are costly, but they have a definite ap- plication under certain conditions. Experiments have been carried out with rustless ropes, and he thought that shortly such ropes will be used in collieries. Springs are being manufactured successfully from rust- less material. ¢ Ss International Conference of Cost Accountants The preliminary program of the third international cost conference to be held under the auspices of the National Association of Cost Accountants in Atlantic City, Sept. 23 to 28, inclusive, lists the following among the subjects for discussion: “Actual Costs as Compared with Replacement Costs,” “Sales and Administration Costs,” “Standards as a Means of Reducing Costs,” “The Place of Costs in Business Management,” “Cost Problems of Specific Industries—Steel and Textile In- dustries.” The National Association of Cost Accountants has 20 chapters in different cities in the United States and Canada, and one recently established in Hawaii. Drop Forging Meeting in October The American Drop Forging Institute will hold a convention. in Detroit on Oct. 3, 4 and 5, concurrently with the convention of the Amefican Society for Steel Treating. It is planned to hold two joint sessions of the two bodies. A few months ago the institute and the former American Drop Forge Association joined forces, all members of the latter body becoming automatically members of the institute until July 1. At that time they were given an opportunity of becoming either as- sociate or executive members of the institute according to their eligibility. Executive members are those whose principal drop AGE August 3, 1999 The strips were again sent to the heat-treating d, ae ment and hardened. This method left the side strips that was faced to the fixture dead soft and ily drilled and tapped. The strips were then g assembled in place, drilled, tapped and reany dowel pins without the slightest difficulty. The was very satisfactory because the holes in the matched perfectly with those in the body of the { and precluded the possibility of poor alinement changing of the relation of the holes in hardeni: The application of this method of localized hardening is very wide, but the method involv plies to them all. Saving is effected in many namely, using low-priced steel as compared to thi of high carbon non-shrinking steel, lower mac} costs and elimination of losses from breakage tortion in hardening. forging business is the manufacture and sale of forgings to other than affiliated companies, whil ciate members comprise those who manufacture forgings chiefly for their own use. Associate me join with the executive members in regional] meetings held periodically to consider matters of mon interest to all producers of drop forgings for ever purpose, as well as in the annual conv Executive members in addition meet five times a y: consider questions primarily of interest to the mercial forger only. It has been decided that all producers of drop ings will be asked to participate in the October co tion on exactly the same basis as active members institute. With the added attraction of the con proceedings of the American Society for Steel Tr: and the international steel exhibition the large tendance of any drop forging convention is expect New Switches for Electric Tool Handles Two new types of compact electric tool and app! switches have been brought out by the Cutler-Ham Mfg. Co., Milwaukee. One, designated as the No. switch, is of the momentary-contact type for inst tion in the handle of such tools as drills. It is p so that when the tool is gripped the forefinger res the trigger pressure which turns on the current return spring causes the trigger to return to the “ When the G Released the 8 Automatically Off the Cur position so that when the grip is released the sv automatically cuts off the current. Long phos; bronze contacts of generous proportions and a wipll motion are features intended to add to the servicea of this equipment. A No. 7039 switch having a different form of op¢ ing lever with no return spring has also been deve for use in vacuum cleaners and similar applia! where the switch is to remain in the “on” or position until moved to the other. 3oston pig iron interests have organized as the |: Monger League, Puritan Chapter, with E. Art Tutein, president; J. O. Henshaw, vice-president, and W. J. Lavelle, sales manager New England Coa & Coke Co., secretary and treasurer. The chapter held its initial outing on Wednesday, July 19, at th easy Winchester Country Club, Winchester, Mass., as guests ae of Mr. Tutein. S nti-Friction Bearings in the Steel Mill Development of Ball and Roller Bearings—Considerations Affecting Their Use Advantages and Disadvantages BY A. M. MAC ~y LIMINATION of friction has always been a most 4 The use of rollers under a block of stone was to the ancient Egyptians. Wheels used on marked the first development in changing friction, between the ground and the weight, bing friction in an axle. Crude ball bearings rst considered about 1862 to 1870, the Patent es showing several patent applications at about me. But the first practical applications came in 1eties, with the use of the cup and cone ngs on bicycles. leed, the history of the anti-friction bearing is lentified with the development of the bicycle automobile. This industry furnished the yr intensive effort toward the production of a more general in its application. first type of annular or ring ball bearings was i about 1901, based upon investigations mad fessor Strybeck. The annular bearing consists ndependent concentric rings, of practically ar section, and with grooved raceways in the irface of the inner ring and the inner surface of er ring. In this groove a row of balls is placed, whole is a self-contained, non-adjusting bear- was recognized that, theoretically, the annular should contain as many balls as the space per- The number of balls which may be introduced earing is intimately connected with the method mbly, which will be discussed in greater detail the various types of bearings. One method, with the side of the bearing, permits the maximum of balls, but breaks the continuity of the race, lally necessitates a shallower groove. ‘ther method, the Conrad patent, the introduc- the balls takes place by means of an eccentric lent of the rings in relation to each other. iber of balls which may be introduced is limited, eway is continuous and deep grooves may be type of bearing, which has been very largely was developed with a roll not solid but made up piral. Considerable difficulty was experienced misalinement, and the consequent stresses not 1 in the design. In 1906 a native of Sweden a two-row annular bearing with a self-alining which it was claimed eliminated the sensitive- misalinement. Another claim for the double- ring is the increased number of balls which may luced in such a bearing. 1905 the first commercial application of annular irings was made in America, although these designing engineer, Reliance Electric & Engineer- veland, Abstract of a paper read before the Pie 3 n of Iron and Steel Electrical Engineer CUTCHEON”* bearings had been previously used abroad. The appli- cation was on a marble polishing machine for the Em- pire City Iron Works, in Long Island, and proved satis- factory. At about the same time, ball bearings were first applied to electric motors, and the two electrical manufacturing companies who were the pioneers in the use of ball bearings for motors are still using them. In 1905 ball bearings were being favorably consid- ered by the automobile industry, and during that year they were applied to the transmission of a 50-hp. Thomas flyer. In 1906, an Apperson car, built for the Vanderbilt Cup race, had its transmission so equipped. In 1910 one machine tool company exhibited at Atlantic City and elsewhere a vertical spindle ‘drill press mounted on ball bearings, which drove a 1%-in. drill through 31 in. of cast iron per minute, and a 3%-in. drill through 11% in. of metal per minute. This, of course, he bearings. Also, thrust on meant a very heavy end thrust on t in 1910, ball bearings were used to take the belted vertical milling machines It is interesting to know that ball bearings have been used, also, on power punch presses, where there is un- doubtedly a very heavy shock condition. The claim Is made that, on such a press, the use of anti-friction bearings decreased the idle stroke power 54 per cent and the working stroke power 20 per cent, and that the power saving for the complete cycle was 40 per cent. Nineteen hundred and ten marked another interesting application of anti-friction bearings to a cold saw, which n at 4100 r.p.m. Plain bearings had required re- A newal about once in three weeks, with consequent shut- down of the machine. Tw nty np. was required } A A Fie. 2. ¢ ERecer \ | A Ba A} | Y a to drive the saw when equipped with o type bearings, and water cooling was employed. After the change in the bearings, a 7%2-hp. motor was substituted for the 20-hp., and there is no evidence of further bearing trouble. In the catalog published by one anti-friction manu- facturer is listed a bearing 4-in. outside diameter and weighing a few ounces, while the largest is over 19 in. outside diameter and weighs approximately 300 Ib. Special large radial bearings have been made by this company, having an outside diameter of 32% in. and a bore of 15% in. This bearing, fitted with 34 balls 4% in. in diameter, has a total weight of 1000 lb. and will carry a weight of 80 tons at 100 r.p.m. Many types of anti-friction bearings are being manufactured, to some of which reference has already been made. A classification, with examples of each type, is given, but the information is not complete. 1.—BALL BEARINGS (a) Annular type with deep grooves, balls assembled by eccentric displacement of the races. Hess Bright Ball Bearing Co. Fafnir Ball Bearing Co. 267 4 ‘ : rs : : ‘ : 268 THE IRON AGE August 3, 1999 (b) Annular type with balls assembled through ¢0-operation is essential between the motor m s filling slots, permitting of a large number of balls. turer and the ball bearing manufacturer. ‘ Standard Roller Bearing Co. years ago the electrical engineer of an eastern (c) Annular type with balls assembled by expansion advised selecting a bearing two sizes larger tha of the outer race under heat, permitting of a large cated by a consideration of the load which the number of balls. was expected and guaranteed to carry. He att Gurney Ball Bearing Co. the entire absence of trouble on car lighting ou (d) Annular type with a double row of balls, per- the following of this plan. mitting of a larger number of balls. In justice to the manufacturer of the anti 2 New Departure Ball Bearing Co bearing it should be stated that, since that tis , (e) Annular type with a double row of balls and haustive study has been made of the requirem self-alining features. anti-friction bearings applied to motors, so tha S K F Ball Bearing Co. are in a far better position to-day than at that 2.— RoLLER BEARINGS | specify the safe working load for the bearing. a s = many sources information has been received (a) Self-contained, with the inner and outer races the bearing is selected large enough and p» : forming a cage for the rolls; rolls assembled through applied, no failure will result. This undoubted filling groove. : oe : ; ee ‘ ; ’ extreme view, but is interesting as evidence of t a3 Rollway Roller Bearing Co. , fidence which some users of anti-friction bearing (b) Semi-flexible spiral roll assembled between end in this type. cages, and with the outer and inner races slipped over : (Tots nition ° and within the rolls, permitting easy disassembly, but not capable of taking end thrust. es Hyatt Roller Bearing Co. Saving Rolling Mill Brasses (c) Tapered rolls assembled between end cages, and BY M. E. DUGGAN with tapered races, permitting easy disassembly, taking s . ‘ end thrust, and making possible adjustment for wear. Worn journal brasses often cause rollil Es Timken Roller Bearing Co. spindles to drop at the roll one below the lev . if Practically all types of ball and roller bearings are Power end. W hen this occurs, considerable fric ri assembled with end cages, which maintain the proper ‘ts In the spindles and couplings. While poo: ' : relation in position of the ball and rolls. The proper cation aggravates this condition, there is, never design of these end cages is as necessary as the proper eT Ts lesign of the rest of the bearing. | Manufacture (jyper Brass Line) This is a highly specialized industry requiring spe ‘ial machinery, special materials and special operation. / | : All bearings must be subjected to rigid inspection and es) test. The three most important properties which a \_ AI . : finished anti-friction bearing should possess are (1) A %-In. Steel Shim | Pn) high fatigue limit and strength; (2) high resistance to’ in Place at Botton | == shock; (3) highest possible resistance to wear. f Housing rr Each bar of steel used in the manufacture of balls or rolls and races is tested. The steel must possess Ge Orwng End) | in the highest degree the qualities of hardness, tough- | ness, durability after hardening and resistance to shock. ’ ' | The best balls are made of chrome alloy steel and care- ver iaslge ) fully heat treated. They are hardened clear through, ) LYa'Sieel Shir }y which makes the steel tough and less liable to crack Cc “o, under excessive load. They must be as spherical as it —_—_—— ————— = . is possible to make them. The best grade balls are ; ' ; i round to size within 0.0001 in., an accuracy necessary something radically wrong with a noisy drive, a) to secure uniformity in size, and consequent even dis- rule mill operators take prompt measures to correct , tribution of the load. The manufacture of a ball in- A usual remedy has been to replace the jour volves eleven main operations, as follows: brasses, which resulted in the scrapping of wor! salad Sled Sete even slightly worn brasses long before they had become nage ad oe tae a Sashes meena: soidionindes unserviceable. \ lo ¢ nate int ! A steel riser block placed under each liner, as show! een a tment: the balls are hardened. and then i” the sketch, will help to keep the rolls up to pretty _ drawn, to toughen the steel. — near the normal level line, thus eliminating much of ee ee Surface iit friction. These blocks or plates can be made in sets oversize varying in thickness from % in. up, thus getting a : ‘ ee a a a Is and heavy oil Hossible wear from the brasses. The roll can be ra 8.—Final grinding in Hoffman machine, in which the balls and lowered with the traveling crane by means 0! * ground to within a small fraction of the finished sling under the bottom roll. ' Polishing bal in a tumbling barrel - 10 ee ee, by which the surface is polished The Southington Hardware Co., manufacture! Final inspection and test for hardness, sphericity and hardware, screws, etc., Southington, Conn., at ; a nual meeting last week, elected the following 7 ; The balls are gaged with special machines calibrated for the coming year: James H. Pratt, president; W } 5 with special care, and by the use of an instrument with iam E. Smith, secretary; and F. M. Gridley, treasur } a ; which it is possible to determine the size to an accuracy ‘The directors chosen were: Ex-Governor Marcus ‘ within 0.00005 in. The same care is exercised in the oleomb, Charles Hopkins Clark, Cyrus C. Chan m-nufacture of the races. One bearing manufacturer jain, Bradley H. Barnes, William E. Smith and W. P.E considers it necessary to manufacture his own steel, Vierning. because of the exacting specifications. The steel tubes F of which the races are manufactured are formed by The Norwalk Iron Works, South Norwalk, . forcing a pointed steel tool through the entire length and the Automatic Carbonic Machine Co., Peoria, of a steel bar, which results in a tube free of welds, have combined, the new organization to have laps or seams, and which has a uniform strength and talization of $1,500,000. C. L. Thompson of South N : : texture on its entire circumference. The tubes are walk, will become president. Each company shall finally cold drawn to size, within a very close limit. tinue manufacture of machinery as previous to Selection of Anti-Friction Bearings merger. This includes oxygen and hydrogen a aan pressors, air compressors and refrigerating machin If anti-friction bearings are applied to motors, close both for ammonia and carbonic acid gas. - . : os ad > Factors in Oil Burning Using Cold Air’ Study of Different Conditions of Air Supply with Com- parisons of Cost—Regenerative Furnaces and Steam Boilers Not Considered r use in oil burning practice is divided into ee general classes: A, volume air at pres- ; - . . es below 12 oz.; B, positive alr at pressures ‘ compressed air at pressures above when discharging against atmospheric pres- temperatures is shown to approximately at 1 in. water pressure, and on mes the pressure will double volume, the it 1 Ib. pressure is approximately 350 ., 3200 ft. per sec. ty has two general functions in oil burning: De + the bs sis 1, isi f+ per SU ID e the fuel, and to induce the greatest amount spheric air consistent with good burner, setting ‘e design. Velocity for Atomizing by Air atomizing by air action with satisfactory com- o ynditions may only be secured with fuel having es below 800 sec. on a Saybolt viscosimeter, nsequently burner and setting design must be 1 on air pressure that will produce satisfactory on speeds. ratory results indicate that the speed of back- th a hydrogen-air mixture and at atmospheri and constant pressure approximately * sec. Under the same condition the backfire the liquid hydrocarbons is probably not over sec., but heating the air-oil column entering mbustion chamber by radiant heat speed and with a hot furnace backfire t <ceed 100 ft. per sec., although the most desirab\ ppears to be 60 to 70 ft. per sec from mechanically delivered rature is per f accelerates velocity air is n excess of desirable combustion velocities, and il velocities must be broken down as rapid le, this being accomplished by atomizer, nbustion chamber and furnace design. Air Required for Burning Fuel Oil ft. of air per applies to (juantities of rfect combustion 1250 to 1700 cu. iel are required. The lower ter oils; the higher to the heavier oils. figure ss air is the source of one of the greatest fuel it 5 to 10 per cent excess air should mark mum limit in oil burning practice. Prope f atomizer, setting and furnace and the instal ' the most suitable equipment in p: t in reducing the excess air waste. author showed graphically in his paper wha inticipated in percentage of induced or aspirated The indu rt Ww ASSIS rood atomizer and furnace design. perty of air under the A classification hown ll, averaging about 33 per cent, while under issification it is more than 50 per cent, a pressure air under the C classificatior ver 80 per cent, approaching 90 per ce air required. Air Comparison of Blowers for Delivering the general at some length stics of blower types ordinarily employed iuthor discussed g and criticised the use of the fan type blower i account of the inability of lowers of tli ntain a constant pressure at constant speed irying air delivery openings, and further, be f the lac] f ot mine ronerties of air at low lack of atomizing properties of air at lov a premium must be paid for a selected fue produce satisfactory operating conditions. : of paper read by W. C. Bue Ir pr ent BScons Mueller, Inec., consulting and combustion e1 Se ttsburgh, before the Engineers Society f West r nia, June 6. Copyrighted, 1922, by W. C. Buell Engineers Society of Western Pennsylvan The displaceme slow perates at constant speed and maintains ynstant pressure This type lower is criticized chiefly because a change in the lelivery areas at the burne1 s not reflected in the energy required for operation A relief valve is ordi- narily employed on wers of this type and at constant speed they require constant energy due to the fact that the machine operates at substantially constant volume by the action of relief valve The turbine type machi n operation maintains onstant speed and constant pressure against variable directly with the required to energy varies almost yume, and the ‘lume and consequently only that energy move the air plus the mach \ piston compressor operating at the initial pressure “pt f 15 lb. is an excellent type of machine and the cost ine constant is actually used ied . 4 of an equal volume of air is less than 25 per cent of the cost of air compressed initially to 80 Ib. Either the 15-lb. or the 80-lb. compressor, due to the effect of the *unloader, absorbs energy only in an amount proportional of air actually needed plus the machine the air is f to the amount furnished at substantially con- constant and Stant pressure. Comparative Cost of Air in condensed form the las to 13 different \ table of the author’s gave results of the study completed in detai ts of conditions. On burn a gal. ‘ation 1125 Si assumed requirement of 1500 cu. ft. of oil, this shows that under the A ft. of air are required per ga). air to classifi- an to 825 cu f fuel, while under the B classification 825 to 480 cu ft. of air, and under the C classification 210 to 180 1. ft. must be supplied from the mechanical air mover per gal of fuel burned and further that with electri irrent at 2c. per kwhr., the power cost of supplying ir for 1000 gal. of fuel burned varies: $2.70 to $1.75, V1itn il! ul le | la fication: $1.75 to $2.50 inder the B class itior ind $1.50 to $6.66 with air l! ler tne ( ec] iss ] it T No account is take f ti ist of piping various ystems, as each layout offers problems which cannot e generalized Conclusion Consideratior the udy shows that the proper method of burning s with air under B classification yr with 15 lb. air under the C classification. The con- lusion drawn in the paper may be applied with slight modifications to the combustion of pulverized fuel. The study covers specifical]; the burning of liquid fuel in such industrial furnacs is use cold air, and no attempt has been made to touch the conditions existing in regenerative or recuperative furnaces or steam boilers. In its complete form the study has thirteen charts, bearing on various factors and essential] to a complete msideration of the paper. The labor situation in the eighth federal reserve district is reflected in the compilation by the Federal Reserve Bank of St. Louis from reports received from 200 leading employers in 20 of the largest cities in the district. The number of employees of the reporting interests increased 12,498 or 10.3 per cent (men in creased 10.9 per cent while women increased 7.5 per cent) between June 30, 1921, and June 30, 1922. On June 30, 1921, the number was 23.2 per cent under normal and on May 31, 1922, the total was 17.7 per cent under normal as compared with 15.3 per cent on June 30, 1922. Wages figures on a semi-monthly basis, increased 0.3 per cent. The average per worker ap peared to be $81.90 per half month on June 30, 1921, and $74.45 on June 30, 1922. 269 > ,* 7 } > } > i * 4 ~ “ 270 TH IRON AGE Self-Contained Jig Saw A new self-contained jig saw which represents a departure from the usual design in that there are no overhead belts, no moving parts unguarded and no ten- Sion in the saw blade, has been brought out by the Oliver Machinery Co., Grand Rapids. It is primarily adaptable to pattern and other woodworking shops for interior and exterior scroll work on wood, although it may be used on other material. The new machine, designated as the No. 173, is shown in the illustration. Operated from the front the capacity is up to 36% in. between the saw and the column. With the saw turned at 90 deg. and operated from the side, work of almost any length or practical width may be handled. The highest work accommo- dated under the guide is 10 in. The stroke of the saw blade is 3 in., and saws up to 18 in. may be used. Moving parts of the machine are adequately guarded and the saw blade not being under tension, a broken New Jig Saw Machine in Which There Are No Overhead Belts. No Moving Parts Unguarded and No Tension in the Saw Blade blade would be unlikely to cause an accident. Saw blades are conveniently removed and replaced. The clamping device below the table is automatic and the sliding block in the upper guide-way is intended to provide a rapid and convenient means of inserting the saw. Absence of overbalance load is a feature of the new design and is said to assure a quiet running, vi- brationless operation and better work. The machine may be either belt or motor driven, being a self-contained unit in both cases. Bearings and movable parts are made to compensate for wear. The pitman and cross head are of aluminum and complete control of the machine is by means of a conveniently located foot lever. The table is 39 x 34 in. and is of cast iron. It is mounted on rockers to tilt 30 deg. to right or left and it may be locked in any position by means of a clamp screw and hand wheel provided. When direct-motor drive is employed a flexible coupling connects the shaft and motor. Two saw guides are provided, one above and one below the table, and these may be turned to permit sawing from either the front or side. A slide dump- ing device is provided in the table in front and around the saw, with the knob on the under side. This may be drawn back to permit small cuttings to drop through the table and out of the way. An air blast, by which a continuous flow of air is directed to the front of the saw, is included in the new design. August 3, 129 » New Line of Polishing Machinery A new line of ball-bearing polishing and machinery, two units of which, a single and spindle lathe, are now available, is being broug by the Mitchell Engineering Co., Springfield, Oh The double spindle lathe, known as the N shown in the accompanying illustration. It h: independent spindles which permit the stopping without interfering with the other. Another feat the ball bearing mounting of the spindle, each having three ball bearings and each loose pull Either or both spindles, together with the be: may be removed by releasing the bearing-h clamps and removing the spindle assembly, a ba socket feature being included to assure perfect ment. The machine may be driven from overhead derneath. The ends of both spindles are drill tapped for taper points. The spindles are 2 diameter the full length, except where the whe: mounted, and the length each spindle is 32 it length of both being 66 in. overall. The distan tween wheels is 57 in. The distance from the tight flange to the side machine is 10% in., but can be longer or shorter as required. The machine will take wheels 2% in. The height from the floor to center of spindle is and size of base at the floor is 26 by 42 in. The weight is 950 lb. net. A No. 5 machine arranged for motor drive is available and in this design any wheel speed is o able regardless of the motor speed. In this arrange ment any standard motor may be mounted in the bas of the machine, and the spindles driven by belts. The spindles are started and stopped independently of eac! other by means of a ball-bearing equipped belt tighten- ing device operated by a hand lever. The No. 6 machine is a single spindle unit, the spindle being mounted in four ball bearings and the Double Spindle Ball-Bearing Polishing and Buff: Lathe. The insert shows the manner of mount spindles with bearings assembled loose pulley in two. In this case also the sp together with the bearings, may be removed leasing the bearing housing clamps, the ball and socket feature being also included. In this machine the spind is 48 in. long overall and the distance between whet 39 in. The size of base at the floor is 20 by 26 in., the net weight 600 lb. Samuel T. Freeman & Co., 1519 Chestnut Streé Philadelphia, auctioneers, will sell at public auctio! Aug. 7 at their salesrooms at this address 1742 tons of chill cast forging ingots and 33,405 lb. of finished a! rough turned forging's. The United States Nickel Co., New Brunswick, N. J., manufacturer of shot and ingot nickel, has re- sumed operation at its plant in New Brunswick. rust 3, 1922 NEW ELECTRIC FURNACE ion Type Developed by General Electric Co. for Melting Non-Ferrous Metals General Electric Co. has recently developed and for several months an induction type furnace ; particularly adapted to melting non-ferrous It possesses several important features not vy found, it is claimed, in induction furnaces, slated to extend greatly the field of application. melting chamber, in which the charge is re- melted, and held for pouring, resembles an ordi- rucible, with inclosed top. It has a charging one side and a pouring spout on the other. ; also a door in the cover which may be used for Repulsion Induction Furnace for Non-Ferrous Metals irging or as a vent when melting oily scrap or other terial producing smoke or fumes. listinect from this chamber, but communicating with ugh ports or ducts, is another chamber in the of a hollow cylinder encircling a primary winding ye leg of a laminated iron core. Molten metal in lindrical chamber constitutes the secondary of a rmer, and the heat in the furnace is generated secondary current which flows around the cyl- through the resistance of the molten metal, alternating voltage is applied to the primary lhe secondary chamber, with its associated primary re, is located beneath the melting chamber, partly mpactness of design, and partly because this posi- favorable for maintaining a full secondary small residual charge in the melting chamber iring. This serves to insure uniform power in- 1 uniform rate of heating. ositive unidirectional circu'ation between the g chamber and the heating chamber (secondary) tutes a feature in this furnace. It is found to in uniform composition of metal and uniform rature throughout the bath. This feature has ar value in the melting of finely divided metal, borings or light scrap, since the molten material nually washing against it. circulation is effected by the magnetic force of n, which exists between primary and secondary transformer. The axial displacement of the ry relative to the secondary causes the fluid pres- ie to this force to be greater at one end of the iry cylinder than at the other. The molten ze flows from the end under higher pressure to the , g chamber, with a return flow from the chamber f THE IRON AGE 271 + to the other end of the cylinder, as indicated by the arrows in the drawing. The strength of the circula- tion may be changed, if desired, by shifting the axial position of the winding. The refractory lining for this furnace is constructed of three preformed and prefired parts, which are as- sembled with cemented joints in the furnace. This, in itself, is considered a radical improvement in furnace design, making for a durable lining, and when neces- sary to replace it, for doing so in short time and little expense. This construction has the advantage of per- mitting the inspection, before assembly, of all parts of the lining, with special attention to the surfaces which come in contact with molten metal. The lining is surrounded, in the furnace, by layers of heat insulat- ing material which, together with the compact design of the furnace, reduce the radiation losses to a mini- mum. When starting the furnace it is necessary to prime it with sufficient molten metal to fill the secondary and give a depth of 2 or 3 in. in the melting chamber. The furnace is therefore at its best when operating continuously, on the same kind of metal, as a residual charge must be retained from the previous heat for starting a new one. When melting intermittently, as for day work only, or for a few heats per day, the re- sidual charge must be kept in a molten condition be- tween heats by applying a low voltage sufficient to supply the radiation losses only. If it is desired to change the metal or alloy which is melted, this may be done by emptying the furnace completely and pouring il Molten Metal in the Space Between Two Cylinders Forms f the Secondary ot [ the Induction Form t ; of Electric Energy \ } Transformation and Is in Communica Indicated tion as with the Main Bath Above ’ ¥ SAAHA->\|\ Hy Yyrmarty Seconddrry |_k~~Core in a priming charge of the new metal which has been melted in some other furnace, or, if it is desired merely to change the percentages of the constituents in the alloy, this may be done by adding an increased per- centage of one or more of the constituents to correct the proportions of the residual charge. The furnace, although of recent development, has been used on red and yellow brass and on copper with, it is stated, pronounced success. Future development is expected to extend the field of application to other metals both ferrous and nonferrous. For yellow brass the furnace illustrated has a total holding capacity of 1200 lb., with a pouring capacity of 750 lb. The full pouring capacity of 750 Ib. can be melted and poured each hour with an input of 75 kw., thus giving a power consumption of not more than 200 kwhr. a ton for brass. For intermittent operation this energy consumption is, of course, increased by the power necessary to supply the radiation loss during standby periods, which is about 10 kw. The power factor on a 60-cycle circuit is about 75 per cent, varying somewhat with the composition of the metal to be melted. The metal loss is almost negligible, being put at less than 1 per cent for yellow brass having a com- position of 60 per cent copper and 40 per cent zinc, and 2 a aggro ae e , * eo . ° a : } +3 : , . ’ ; ’ M j . . : u ‘ . ~ - * ‘ “ ® , 272 THE IRON AGE — ls as have higher copper centent. Stlll less tor sucn meta This furnace will be built in two forms, which are practically the same except for the tilting mechanism and method of tilting. The furnace proper, which is the same in both forms, is mounted on a strong steel frame or yoke, which is provided with trunnions sup- ported in bearings on pedestals. In the form here illus trated, the trunnions are so located at opposite ends of the yoke that the furnace tilts around a line approxi- mately through its center of gravity, the pouring spout August 3, moving forward and down. In this form of the fy the tilting is accomplished by means of a hand suitably geared to the trunnions. In the other for trunnions are located on a line passing throug ; pouring spout, so that in tilting there is no mot ‘ee the spout. This type of furnace is used when it ; sired to pour directly from the furnace into In this form of the furnace the tilting is accomp by means of a motor, which is controlled by a sta drum switch. Rolling Mill Equipment Merger Is Completed Mackintosh-Hemphill Co., A. Garrison Foundry Co., Pittsburgh Iron & Steel Foundries Co. and Woodard Machine Co. Now a Single Corporation with Capital of $6,500,000 PITTSBURGH, July 31.—Official announcement has been made of the merging of the Mackintosh-Hemp- hill Co., the A. Garrison Foundry Co. and the Pitts- burgh Iron & Steel Foundries Co., first news of which was published in THE IRON AGE, March 16, 1922, page 743. Included in the combination, which takes the name of the Mackintosh-Hemphill Co., is the Woodard Ma- chine Co., Wooster, Ohio, an interest of the Mackintosh- Hemphill Co. Negotiations were completed more than a month ago, and the official announcement was de- layed pending a meeting of stockholders of the Mack- intosh-Hemphill Co., approval of which was necessary to the consummation of the deal. The merger has been recent pr ict Mr. McClurg was JAMES HEMPHILL } accomplished through the purchase of the stock of the A. Garrison Foundry Co. and the merging of the Pitts uurgh Iron & Steel Foundries Co. and the Woodard Machine Co. in the Mackintosh-Hemphill Co. The cap tal of the last named company has been increased from $1,000,000 to $6,500,000, consisting of $2,850,000 7 per cent cumulative preferred stock, all of which has been issued, and $3,650,000 common stock, of which $3,000,000, or 30,000 shares of par value of $100, has been issued. This increase will provide for the ex- change of shares in the Pittsburgh Iron & Steel Foun- dries Co. and Woodard Machine Co. into Mackintosh- Hemphill stock. An issue of $4,000,000 27-year 6 per cent sinking fund gold bonds has been authorized by the Mackintosh-Hemphill Co., and of this $3,000,000 has been put out to provide funds to complete payment for the properties of the consolidating companies, for the payment of existing mortgages and bank loans, and to furnish additional working capital for the new com- pany. A committee on which George S. Macrum, George W. Baum and Joseph E. Fawell represented the Mack- intosh-Hemphill Co. and the Woodard Machine Co., and J. Ramsey Speer and H. V. Blaxter, the Pittsburgh Iron & Steel Foundries Co. and the A. Garrison Foundry Co. conducted the negotiations. The officers of the new company are: Pennock Hart, chairman; George S. Macrum, president and treasurer; G. W. B Joseph E. Fawell and L. A. Woodard, vice-presid D. H. Baum, secretary, and A. W. Bendig, ass secretary and assistant treasurer. This merger has an historical significance, in t] reunites foundry interests which trace their orig the first foundry established in Pittsburgh. The cipal stockholders in each of the companies ar scendants of the original owners and their assoc J. H. Ricketson, Jr., and O. G. Ricketson, retiring cers of the A. Garrison Foundry Co., are grandsons of Abram Garrison, to whom the success and reputa of the Garrison company is largely due. Pennock H one of the build- ers of the first Pittsburgh foun- dry 119 years ago, and Mr Garrison's name has been con- nected with the same business since 1836 ABRAM GARRISON chairman of the board of directors, Mackintosh-H: hill Co., is the son of N. F. Hart, one of the found of Mackintosh-Hemphill Co.; George Macrum, p1 dent, is a son-in-law of William Wade, whose nam appears prominently in the early history of the F Pitt Foundry; G. W. Baum, vice-president, is a so! law of James Hemphill; and J. Ramsey Speer J. McK. Speer are great-grandsons of Joseph McClurg, who founded the Pittsburgh Foundry, and of Wil! McKnight, who with Mr. McClurg operated the p for a number of years during its early histor Charles McKnight is a grandson of William McKnigh' The McClurgs and McKnights also were active in t early history of the Fort Pitt Foundry. It is doubtful if larger contributions have bee! ve made to the success of the iron and steel industry tha! a those made by the members of this group. The earliest ee rolling mill and blast furnace engines, the rolls for th au various requirements of the mills, the most effectiv pipe balls in the earlier days, all testify to the skill anc knowledge of those who headed these companies. First Foundry in Pittsburgh The first foundry in Pittsburgh, and probably the : first one west of the Allegheny Mountains, was built !! Oa 1803, on what is now the site of the Park Building, at Fifth Avenue and Smithfield Street, by Joseph Mc- 3 1922 THE IRON AGE 273 nh Smith-and John Gormley. It was called gh Foundry. Shortly after its establish re 1807, Joseph McClurg bought out his and w.th his son, Alexander McClurg, business until 1814. The early years of Foundry are particularly interesting, here that many of the cannonballs used by Perry at Lake Erie, and by General Jack- Orleans in the War of 1812, were made. d of this war, the foundry was devoted to 3 mn of water pipe, stoves and miscellaneous castings. The record of the ownership urgh Foundry shows remarkably few ind almost a continuous line of descent families of the original owners and thei1 814 to 1822 it was owned and operated by McKnight. From 1822 to 1830 by Alexan re & Co. At this time it was merged with and Eagle foundries, owned by Kingsland From 1831 to 1840, the firm was known 1, Lightner & Cuddy. In 1836 Abram tained an interest in the business, and in Garrison, who was a nephew of Mr. Kings- H. L. Bollman, a nephew of Mr. Lightner, their uncles, and associating with them H. F. nducted the business under the name of & Garrison until 1851, when H. F. Bollman From 1851 to 1863, the firm was Bollman and from 1863 to 1865 Bollman, Garrison In 1864 Mr. Bollman retired, and in 1865 the » of A. Garrison & Co. was formed. The is incorporated under its present name in In 1852 the original location at Fifth Avenue thfield Street was given up, and the foundry 1 to its present location on the south side of ngahela river between Ninth and Tenth ee ise of the failure of Mr. Garrison’s health in tive management of the business was his son-in-law, J. H. Ricketson, who held dency until his death in 1900. He was su his son, J. H. Ricketson, Jr., who has had if the company up to the present time. First Chilled Rolls chilled rolls made west of the Allegheny ere cast in 1825 at the Eagle Foundry of Lightner & Co. After the merger of this th the Pittsburgh Foundry in 1830, the im the development of rolls and rollin was appreciated. Almost the entire ca .e foundry up to the present time has | production of rolls and rolling mill equip : y for use in the rapidly expanding ste« it also for rolling brass, copper, zine and rrous metals. In 1842, the first chilled ng sheet brass made in this country were Bollmans & Garrison to the mills of the Valley in Connecticut. Rolls for this serv isly been imported from England. Mr iccess in making these rolls resulted in the f American made rolls by most of the brass heet makers. ge obtained by the manufacture of the lls in the Pittsburgh district has been aintained. The names of Pittsburgh ; | later A. Garrison Foundry Co. are na ated with the development and produ ed iron rolls. The company also has be nt in the designing and constructing of bles and auxiliary equipment for the ictural and sheet mills. However, its not been confined exclusively to the de the small mills. It has designed and in in. plate mill which requires chilled iron re diameter, weighing 72,000 Ib. Established in 1837 ¢ alvin Adams established in Pittsburgh a foundry for making pump plungers and ngs. It enjoyed continued success, though scale, and later the firm became known as s Adams Co. Under the management of S. Jarvis Ad S inde e company