The Iron Age 1909-07-15: Vol 84 Iss 3

THE IRON AGE Published every Thursday Morning by David Williams Co. 14-16 Park Place, New York. Vol. 84: No. 3. New York, Thursday, July 15, 1909. jase doe Reading Matter Contents ....... page 234 _— = a : —— Alphabetical Index to Advertisers ‘‘ 200 ii Classified List of Advertisers “ 190 Advertising and Subscription Rates “ 239 REED F. BLAIR & CO. FRICK BUILDING, PITTSBURG, PA. STANDARD CONNELLSVILLE COKE TRADE MARK Subject: How Would You Like to Sell Out? Did you ever stop to think what your business is worth — just how much cash you could get for it if you had to sell quick ? POUNDRY FURNACE CRUSHED The original and only Genuine ‘‘STILLSON WRENCH *’ is manufactured by “a. WALWORTH MFG. CO., Boston, U.S. A. And bears their registered Trade-Mark Suppose you stopped to-day and took inventory. Do youknow that if all of your stock were as well known and as well advertised as UMC shells and cartridges you could realize practically 100c. on the dollar? UMC Metallic Cartridges are made for Remington, Savage, Winchester, Marlin, Stevens, and all other rifles by cartridge specialists. UMC Shot Shells are Steel Lined, but no others are. You can see the UMC advertising campaign in all leading publications. The UMC trade mark is insurance against dead loss stock. Do you specify UMC shells and car- tridges from your jobber? THE UNION METALLIC CARTRIDGE CO. en ae ane s BRIDGEPORT, CONN. No 104 Agency, 315 Broadway, New York City WATER TUBE The Babcock & Wilcox Co., BOILERS See page 56 - — BRAIDED CORD Samson Cordage Works, Boston, Mass. THE DEMAND CONTINUOUS <a — “The Capewell” Cleveland City an co Co., Cleveland, 0. | Horse Nail TURNBUVUOCEHEES Its Holding, Driving and Selling qualities MERRILL BROS. | : fet Maspeth, | are found superior to all other horseshoe New York, N. Y. nails. $3 ¢s FOUNDRY IRON Ge ae Real Estate Trust Bidg., Phila, THE CAPEWELL HORSE NAIL COMPANY, Piliing & Crane Empire Biog., New York HARTFORD, CONN., U.S. A. eee UFHIN \= | . JENKINS °96 RULES || Jipguemmea Tres reece is the most economical sheet packing to use—because : . a MADE IN AMERICA and 1) a paces! ates ae ‘an aoe . , : || - 5 5 ght per square yard is less than most packings, THE BEST IN THE WORLD || '@ ieee aes Ye ) and consequently it costs less. Also an allowance will Tay LUgETS as mn *paneiney ieee’ U.S.A. i ; SA eA acs $ be made for clean scrap cuttings returned to our factory. ew Yor on, ; dsor, Can. Mh eet eee 0) The genuine bears our Trade Mark. JENKINS BROS., New York, Boston, Philadelphia, Chicago. You will have nothing to make right on apoio gest crow 4|‘swedoh” Gold Rolled Steel," Drawing = Stamping GALVANIZED SHEETS {Water and Rail Delivery)» Buiboxont, CONN. page 25 —- MAGNOLIA rei%ox METAL The Standard Babbitt of the World We manufacture everything in the MAGNOLIA METAL CO. Chicago: Fisher Buildings Montreal: 31 St. Nicholas St. They are right to start with AMERICAN SHEET AND TIN PLATE COMPANY Frick Bullding. Pittsburgh, Pa. See our ad on page 17 New York: 115 Bank St. MORE HIGH STANDARDS ‘‘ FOLLANSBEE BLUE” AND ‘‘FOLLANSBEE POLISHED” STEEL SHEETS These two brands are now used by many of the largest concerns in the country. Even color (oiled) for stoves and other stove pipe, also elbows purposes requiring a fine appearance. THE IRON AGE BRASS}*",. GERMAN { steet SILVER | "8 tng Pat, Leveled Sig) Brass jeer. css" st tmran sun race No Buckles, Clean Surface, || 1RON AGE READERS | Polished or Plain Steel Stamps and Dies, Time Checks PAT. LEVELED GERMAN SILVER ee Polished or Plain for Soda serine sabes edie Water and Bar Fixtures Matthews of Pittsburg Low Brass, Gilding and Bronze Metal, Sheet, Rod and Wire FOUNDED 1850 Manufactured Goods SCOVILL MFG. CO. in Great Variety Waterbury Brass Co. The Plume & Atwood Mfg. Co. Manufacturers of Sheet and Roll Brass, Wire, Rods, German Silver and Brass Goods in great variety WIRE | Rolling Mill Factories BRASS, GERMAN SILVER, Sheets, — Wire, and 5. WATERBURY, CONN. 1 Cliff St., New York Providence, R. |. Bridgeport Deoxidized Bronze & Metal Co. BRIDGEPORT, CONN. ¥ FOLLANSBEE BROTHERS COMPANY PITTSBURGH Bronze Composition, Yellow Brass and Alumi- num Castings, large and small Matthiessen & Hegeler Zinc Co. LA SALLE, ILLINOIS SMELTERS OF SPELTER AND MANUFACTURERS SHEET ZINC AND SULPHURIC ACID Special Sizes of Zinc cut to order. Rolled Battery Plates Selected Plates for Etchers’ and Lithographers’ use. Selected Sheets for Paper and Card Makers’ use. Stove and Washboard Blanks. ZINCS FOR LECLANCHE BATTERY (GERMAN SILVER WIT \ | In Sheet, Wire, Rods, Tubing and Blanks. | Polished wide sheets, patent levelled, for soda foun- | tains, bar fixtures etc. German silver for spinning. | | NICKEL ANODES SPARS, HRONER, COPPER | \ THE SEYMOUR MFG. CO., Seymour, Conn. Vi HENDRICKS BROTHERS : Sheetand Bar Copper, Copper Fire Box Plates and Staybolts, Wire and Braziers Rivets Importers and Dealers in Ingot Copper, Block, Tin, Spelter, Lead, Antimony, Bismuth, Nickel, etc. 49 CLIFF STREET - - NEW YORK TRAD: Brass Shells, Cups, Hinges, Buttons, Lamp Goods. Special Brass Goods to Order. Factories WATERBURY, CONN. Depots : NEW YORK CHICAGO BOSTON Phosphor and Deoxidized Henry pouther Engineering (0. HARTFORD, CONN. Consulting Chemists, Metallurgists and Analysts. Complete Physical Testing Laboratory. Expert Testimony in Court and Patent Cases. Arthur T, Rutter & Co, 250 Broadway, NEW YORK. Small tubing in Brass, Copper, Steel, Aluminum, German Silver, &c. Sheet Brass, Copper and Ger- man Silver. Copper, Brass and German Silver Wire. Brazed and = | Seamless Brass and Copper Tube. Copper and Brass Rod. “PHONO-ELECTRIG” WIRE. “T'S TOUGH” TROLLEY, TELEPHONE TELEGRAPH LINES. BRIDGEPORT BRASS COMPANY Postal Telegraph Bld Broadway and Murray 8t., Mills Beidgeport Conn. Kew York PHOSPEOR-BRONZE GERMAN SILVER THE RIVERSIDE METAL CO. RIVERSIDE, N J. THE IRON AGE New York, Thursday, July 15, 1909. Mesta Air Compressors. The range of heavy duty machinery built by the Mesta Machine Company, Pittsburgh. Pa.. has been extended to include air compressors. Two large ones were recently completed for the Pittsburgh-Buffalo Company to be in stalled in its mines at Marianna, Pa., which are to be the largest and best-equipped coal mines in the world. The illustration shows one of these compressors as it ap- peared on the erecting floor, prior to shipment, from which it will be seen to follow the lines of the Mesta heavy duty rolling mill engines. It is a cross compound two-stage compressor, having a capacity of 3€00 cu. ft. of free air per minute delivered at 100 lb. pressure when appearance of the machine in the power house. It is also preferable to have the intercooler below the floor on ac- count of the condensation on its surface which is contin- ually dripping on the machine if the intercooler is placed overhead. A special feature of this intercooler is the means provided for passing the cooling water in a com- paratively thin film along the walls of the pipes, which is expected to reduce the quantity of cooling water used to about one-half to one-third of an intercooler with plain pipes. A pressure regulator is attached to the main engine governor and operates a floating lever. The air pressure acts on a plunger which is held down by a weight and spring. The plunger is a ground fit in a cylinder, and no packing of any kind is being used. The pressure reg- the amount necessary in The First Large Air Compressor Built by the Mesta Machine Company, Pittsburgh, Pa. running at 75 rev. per min., and its total shipping weight is 200,000 Ib. The compressor is of the rotative crank and fly wheel type with air cylinders connected in tandem to the rear end of the steam cylinders. The steam end is of Corliss type with a high-pressure cylinder 22 in. diameter, a low- pressure cylinder 36 in. diameter and a stroke of 48 in. The low-pressure air cylinder is 34 in. diameter and the high-pressure 20 in. diameter. The compressor valve gear consists of semi-rotary inlet valves positively driven from an eccentric on the main shaft and automatic poppet out- let valves; the latter are of a new improved design and are practically noiseless in operation. All vaives are located in the cylinder heads which reduces the clearance to a minimum. The cylinder and cylinder heads are effectively water- jacketed. A large intercooler is also provided between the first and second stages on the compressor, which, being located below the floor line, also makes it possible to keep all piping, except the discharge from the high- pressure cylinder, below the floor line, and improves the ulator in connection with the engine governor will vary the speed of the machine to suit the demand for air and is calculated to keep the air pressure within 1 per cent of normal. The Mesta Machine Company has entered this field, believing there will be a demand for such heavy duty machines and it is the intention to build only larger sizes and for very heavy duty. The company has also built for the Marianna mines of the Pittsburgh-Buffalo Company a 26x48 in. heavy duty simple Corliss engine directly connected to a 500-kw. generator. This engine has been in operation now about eight months and it was its satisfactory performance under the very variable con- ditions of load existing that prompted the Pittsburgh- Buffalo Company to contract with the same builder for the above mentioned compressor, and also for a large first motion hoisting engine although neither of these machines has been built before by the Mesta Company. The hoisting engine is a 36x60 in. twin machine with con- ical drums and is expected to be put in operation by 4 November 1. 176 Brown & Sharpe Miller Tests. At the recent Master Mechanics’ and Master Car- builders’ convention in Atlantic City the Brown & Sharpe Mfg. Company, Providence, R. I., exhibited two milling machines and a full line of milling machine at- tachments. The results obtained on the machines in tests which were made are recorded in the following: On the No. 5-B plain milling machine, from a piece of steel of 65,000 Ib. tensile strength, 18 cu. in. per minute were removed at a feed of 16 in. per minute and surface speed of 60 ft. per minute. The cut taken was 6 in. wide and 3-16 in. deep. It is reported that at no time during the running under such severe strains did the machine show signs of distress or appear to labor excessively, and the noticeable absence of vibration from all parts was one of the impressive features of the demonstration. A nickel was placed on edge at one end of the table and a full glass of water at the other end. Cuts were taken with so little vibration that the nickel | did not fall nor any of the water spill from the tum- bler. A gang of two cutters of 3% in. in diameter was used in this test. On the No. 3 vertical: spindle milling machine 9.375 cu. in. per minute were removed at a table speed of 12% in. per minute anda surface speed of 60 ft. per minute. A cut 6 in. wide and %& in. deep was taken at each traverse of the table. The cutter used was a 9%-in. inserted tooth face mill. The same tests were applied to this machine as the No. 5 machine. Both machines were motor driven by General Electric direct current motors. That for the No. 5 machine was of 20 hp., and the one for the No. 3 machine of 10 hp. capacity. The amount of stock removed per horsepower consumed was 0.85 cu. in. on the No. 5 and 0.88 cu. in. on the No. 3. The performance of one gang of cutters used on the No. 5-B heavy plain milling machine was rather remark- able. The cutters cut 1800 cu. in. of steel without hav- ing to be removed from the arbor for sharpening. The — great rigidity of the machines and the effectiveness of their weight in absorbing vibration, their high efficiency and their excellent condition at the end of these severe tests are important as reflecting the excellence of design and construction of the machines. oe An American Exposition at Berlin. An American Exposition will be held in the city of Serlin, Germany, during the months of April, May and June, 1910, in the Exposition Palace near the Zoological Garden, located in the best and most frequented part of the city. ; Prominent citizens and business men on both sides of the Atlantic will co-operate to make this exposition suc- cessful. The European management will be in the hands of men previously experienced with expositions. Max Vieweger, Hudson Terminal Buildings, 50 Church street, New York, is American manager: for the exposi- tion, and is distributing literature giving the details of the enterprise, with information regarding the applica- tions for space, rates charged, etc. An appeal to Ameri- can industries, urging representation at this exposition, has been made by a considerable number of prominent citizens. Among them are the names of heads of repre- sentative manufacturing establishments. The statement is made that the exposition will be unique in that the price of space per square foot will include those inci- dental expenditures which are ordinarily most annoying te exhibitors. The exposition is intended to educate Europeans, espe- cially the people of Germany, on the importance and ex- cellence of American manufactured products, and thus strengthen the existing cordial relations and stimulate trade between the two countries. The English company, J. G. White & Co., Ltd., at its annual meeting, declared dividends of 8 per cent. on the preferred and common shares for the fiscal year ending February 28, 1908. The company’s reserve fund stands at £100,000, and the profits carried forward amount to £15,460. THE IRON AGE July 15, 1909 The Brown Electric Recording Pyrometer. A new instrument, Fig. 1, for use in conjunction with a thermo-couple as a thermo-electric recording pyrometer has recently been designed and patented by Edward Brown & Son, 311 Walnut street, Philadelphia, Pa. This type of recording gauge can also be used for accurately recording pressure of steam and air, or an electric volt or milli-voltmeter, &c. As a pyrometer the complete equipment consists of a thermo-couple, as illustrated in Fig. 5, consisting of two nickel alloy rods suitably insulated and protected, the recording electric pyrometer and the leads or wire for connecting the thermo-couple and the recorder. The length of the leads are commonly anything from 100 to 500 ft., and very frequently the same thermo-couple which generates the current for the recorder also actu- Fig. 1.—The Electric ‘Retording Pyrometer, Made by Edward Brown & Son, Philadelphia, Pa. ates an indicating ils on the same circuit, but located near the furnace for the operator’s guidance. The electric recording pyrometer gauge consists of a x milli-voltmeter system carrying a small drop of ink on the pointer or needle. As this milli-voltmeter system is in a horizontal position, there is no change in weight or position of the pointer with an increase or decrease of ink. An 8-in. chart of stiff white paper is raised once a minute by a powerful eight-day clock movement and touches the ink pen, making a small dot on the chart. These continuous dots form into a fine line, and as the pen is only in contact with the chart an instant the pointer is able to fluctuate readily with the rise and fall in temperature. This momentary contact with the paper is necessary in an electric pyrometer, as the current which is produced by the thermo-couple and which actu- ates the needle is so small that the friction of the needle on the paper, if it was in constant contact, would retard the needle and render the reading inaccurate or hold it from movement altogether. In order that the chart may be readily removed from the instrument without the danger of striking the pointer or necessitating the moving of the system, the chart and clock mechanism axe carried on a drawer which can be withdrawn, as illustrated in Fig. 2. This drawer is car- ried on ways or guides, causing the drawer to be low- ered as it is drawn out and preventing the pointer drag- ging a line across the chart. The drawer can either be July 15, 1909 withdrawn part way, as shown in Fig. 2, or can be with- drawn entirely, as shown in Fig. 3, and the chart re- moved and a fresh one placed in position. It is much simpler to change the charts on a recording pyrometer when lying on a table or shelf than when in the record- ing case. Once a day, when changing charts, a drop of ink is placed in the recording pen with a dropper or pointed article. Occasionally also it is desirable to pass a camel’s hair brush dampened with water through the recording pen to clean it and insure a fine ink line. To enable this to be easily attended to a frame is raised from the base of the recording instrument as the drawer is withdrawn and forms a rest for the pen pointer, as may be seen in Fig. 2. The Brown Electric Recording Pyrometer. Fig. 2. Although the parts of the recording instrument are well protected by the case, the milli-voltmeter and the clock mechanism are both enclosed in metal cases as an additional protection from dust. Where it is desirable to record the temperature of several furnaces these recorders can be supplied to re- cord 1, 2 or 4 furnaces, all records being made in one ease. Fig. 4 illustrates a quadruple electric recording pyrometer for recording the temperature of four furnaces, which makes a desirable equipment for many large works. The recording electric pyrometer can be sup- plied for any desired range in temperature, and the record charts can be made to revolve once in 24 hours or 7 days, if preferred. In Fig. 6 a reduced facsimile of a record chart is shown. This chart shows the form of dotted red line made by the Brown recorder and incidentally shows that the fireman attending this furnace neglected his work for about 214 hours during the night, as shown by the drop in temperature. These pyrometers have already been supplied for use THE IRON Fig. 5. AGE 177 Wig. 4. WSs J Ol__— iN Dl ~——— ————— SS at a number of blast furnaces and for annealing ovens, glass melting furnaces, brick kilns, and other operations where a clear record of the temperature is desirable. Excess Speed Alarm for Motor Vehicles.—The Lon- don 7'imes Engineering Supplement describes an auto- matic mechanism which is being brought out by an Eng- lish manufacturer in order to meet the forthcoming regu- lation to be issued by the metropolitan police, to the effect that mechanically propelled vehicles will be required to be provided with a device to give audible indication when- ever the legal limit of speed is exceeded. The apparatus consists of a gong mounted on the car and arranged so as to be struck by a rotating lever which flies outward into contact with projections on the gong when the speed of the vehicle is excessive, the lever being actuated from the shaft or other moving part of the engine, The mech- anism can be adjusted to suit any speed of engine, size of wheel or speed limit, and when once adjusted it can be sealed by the authorities, - ae A AES ee Pt ast tated ke 178 THE IRON AGE July 15, 1909 THE SHOP POWER PLANT. Suggestions to Guide the Selection of Equipment. BY CHARLES L, HUBBARD, AUBURNDALE, MASS. In the average shop probably mest study to improve economy is given to the cost of turning out the particular product manufactured. This is preper, but other less important items sheuld not be everleoked, among them the power plant. Dhe following aims to give briefly matters to be observedin the selection of new apparatus ; methods of obtaining the size of boilers, engines, aid auxiliaries for differemt requirements, and ways of in- creasing the present ‘power of a plant while keeping within the bounds of reasonable economy. No attempt will be made to go into thé @ifferent matters with the accuracy and detail necessary in the case of large elec- tric plants. The subject will be treated rather from the standpoint of the shop owner or superintendent than from that of the mechanical or steam engineer. Selection of Apparatus, Boilers.—The choice of a boiler will usually lie be- tween the ordinary horizontal fire-tube and one of the throughout the country use the horizontal fire-tube boil- ers. They cost less, have a greater water capacity, which gives a less rapid fluctuation of the water-line and thus require less careful attention, and when properly de- signed and cared tor and inspected at regular intervals are comparatively safe against explosion. In selecting a tubular boiler. the manufacturers’ tables of dimensions for different capacities should be used with caution. Boilers of this type used for power pur- poses are usually rated on a basis of one horsepower for each 12 sq. ft. of heating surface. This makes it:a temptation on the part of the manufacturer to crowd as many tubes as pessible into a shell of a given size to give it the maximum rating at the least cost. ‘To get the best results: there should be a good space above the tubes for the separation of the steam from the water to secure dryness. and there should also be ample room for the circulation of water between the shell and tubes and =00D000-500006 -O1000010_0O0DD00O 3 —O7 ODDO: OD0- O- SS ODSS 4 Sections Through Two 100-Hp. Boilers. tmany forms of water-tube boilers. No particular rule ean be followed in the selection of a boiler, as much will depend upon the maximum price to be paid, pressure to be carried, available space, &c. Generally speaking, when boilers of any of the well-known types are equally well designed and proportioned for the work to be done, and are operated with the same skill, and provided with the same quality of fuel, one type will give about the same economy as another. This leaves the owner free to choose a boiler best suited to his own taste and to any local requirements which may exist. If the plant is of considerable size, carrying a high pressure, and the boilers are located in or near a build- ing containing a large number of operatives, the matter of safety should be given especial weight. Here the water-tube boiler has the advantage, as the water is divided into small masses, which tends to prevent serious results in the case of rupture. Among other features of thé water-tube boiler may be mentioned a large amount of fire surface, causing a more rapid circulation of the water, with a decrease in the liability of both overheat- ing and the accumulation of sediment and scale; or large draft area through the tubes, resulting in a slower move- ment of the gases and a greater absorption of heat; the losses from the accumulation of soot and ashes is less than in the case of fire-tube boilers, as they do not adhere so readily to the outside of the tubes as to the inside. All of these features tend to economy. Probably the greater majority of the machine shops also between the tubes themselves. In general, there should be a clear space between the tubes in both direc- tions of one inch, with a 2-in. vertical space at the cen- ter, and at least 3 in. between the tubes and the shell at the sides. Figs. 1 and 2 are each sections through a 100-hp. doiler. They are of the same diameter (60 in.), but the first contains 94 3-in. tubes 12 ft long. while the second has 72 tubes of the same size 15 ft. long. The propor- tions of the second boiler are better because there is a larger steam space and more room for the circulation of water between the tubes, and the greater length of the tubes will give better economy in the use of fuel, as more opportunity is allowed for the absorption of heat. The defects in the first boiler would become more pro- nounced should it be forced above its nominal rating. The number and size of tubes for boilers of different diameters as recommended by the Hartford Steam Boiler Inspection and Insurance Company are given below and will be found useful in checking up catalogue ratings: Diameter Diameter of shell. of tubes. Number Inches. Inches. of tubes. OR ee saa dict 6 og DE ninwats s Dawes DESEO SS 34 ME ease al WE als CEE hie USAT ae Aid eit b oatkee pede Wace 34 Ser eid S3h0 RES Sie Sees: cechin k's Se pa Sek eek oo 44 ed ae PORN aS 5 4.6 EA eh beast ee ein SL 54 Oe se cae ene cee sak 3 CARS RAGD ADR uO RS boas 72 Bee as Cie SOMDIR CRS TR 46 OR ck citi & dns eur te x wows By CUMs 55. bachonawecmee 90 TE4s Gad Vilewye bxirch ome fis Soke s Vi IWSE Se ob 114 so July 15, 1909 The type of bracing is important. Through bracing is of advantage from the standpoint of strength, but is objectionable in all but the largest sizes, as it makes the boilers more difficult to enter for inspection. A good plan is to compromise by using diagonal bracing in the smaller sizes, say from 86 in, to 48 in., a combination of diagonal and through bracing for 54 in. and 60 in. boil- ers, and all through bracing for 66 in. and 72 in. boilers. Figs. 3 and 4 show the usual arrangement of combina- tion diagonal and through bracing. ‘The pressed steel diagonal braces nowyin use are preferable to the older form of crow-foot braces with fork and pim as they are free from welded points and therefore more reliable. The longitudinal seams should be of the butt-joint type, with either double or triple riveting, according to the pressure carried. Lap joints will give sufficient strength when new, but are apt to become weakened by constant expansion and contraction. The thickness cof shell will depend upon the diameter of the boiler and the pressure carried. For a working pressure of 100 Ib. per square inch, with a factor of safety of 6, and double riveted butt-joints, shell plates of best quality mild 3% in. thick may be used up to and including 54 in. eter; 7-16-in. plates may be used for 60 and 66 in. boilers, and ¥% in. for 72 in. If higher pressures are to be car- ried, the plates should be thickened accordingly. Engines.—-The conditions of shop and factory work ‘are usually less exacting upon the engine than those in electric power plants. As a general thing, the load is more uniform, and during ‘the heating season, at least, Q00000.00000: Fig. 3. The Usual Arrangement of Combination Diagonal and Through Bracing. the matter of steam economy is not of so great impor- dance. Uuder these conditions the selection of an engine depends to a considerable extent upon personal prefer- ence, first cost, and the skill required to operate it. In certain up-to-date plants the owners may take an espe- cial pride in the engine room and the results obtained in the way of steam economy, even if this saving is offset to a considerable extent by the increased cost of the engine and the skilled attendants necessary to care for it. Certain locations may be favored with cheap fuel and dhave long heating seasons, in which case steam economy is not of so much importance, and a simple low-priced engine requiring a minimum of attention will be the most satisfactory, while in other cases the conditions ‘may be reversed. Although the regular day requirements of a shop engine may be practically uniform, the matter of lighting must be considered, and this during the short days of the winter months is an item of considerable importance. ‘The question here may be to decide whether it is best to install a separate outfit for lighting or to overload the regular engine for the lighting period, even at a loss in economy. Under these various conditions it seems best to simply give some of the principal characteristics of the different types of engines, from which the shop owner can select the one which seems to be best suited to his “own requirements. The simple throttling slide-valve engine is the cheap- -est and requires least skill in operating. It is adapted to small plants, and where fuel is cheep, or where the exhaust steam can be used to advantage the greater part -of the time. The steam consumption in a well designed engine of this type will run’ from 382 to 40 Ib. per i:h.n. ‘per hour.’ For greater economy either the four-valve THE IRON AGE 179 medium speed engine or the Corliss type may be used. The first of these has a steam consumption of 28 to 32 Ib., is compact, costs somewhat less than the Corliss, has fewer parts and is therefore cheaper to keep in repair. The Corliss is of necessity a slow-speed engine on ac- count of its valve gear. It requires a long but narrow floor space, its economy is good, running from 26 to 50 Ib. of steam per i.h.p. Both of these types are well adapted to shop and factory work of the best class, and require fair operating ability. When the load is fairly constant and economy in steam consumption is important the compound engine may be considered. ‘The first cost is considerably more than for the simple engine, being perhaps 30 per cent. greater under average conditions. On the other hand an economy in steam consumption of 25 to 35 per cent. is not uncommon, while the increase in fuel consumption necessary to raise the boiler pressure from 80 to 125 tb. will not exceed 1,per cent. The greater economy of com- pound over: simple engines is due in part to the reduced _ cylinder condensation, but more especially to the higher initial steam pressure and greater number of expansions. In simple engines the initial pressure is generally limited to 80 or 90 Ilb., and the number of expansions to about 4. Any increase beyond these limits is usually accom- panied by excessive cylinder condensation, which more than offsets any gain from the greater expansion. In compound engines the initial pressure may be carried up to 120 or 140 Ib., which allows of 8 to 10 expansions without excessive condensation. The objection commonly ee me mm me ey 000000 Os. Oe 1 OO0000 OOOO0O0O LL Fig. 4. raised to compound engines is the falling off in economy when underloaded, which is somewhat greater than in a simple ‘engine. The economical range of a compound engine lies between one-half and full load. The following results of a test on a 150-hp. tandem compound engine running at a speed of 250 rev. per min. under an initial pressure of 125 lb. is taken from Steam, July, 1907: OGG Ree Sint 50 to 55 Ib. steam per horsepower-hour. Yo BOGE obi ioe a a 6b TROL 35 lb, steam per horsepower-hour, Me, ROM a gd dinth arow vhite oe caliente 28 lb. steam per horsepower-hour. DUE COO so 53 & hve Cocen kes 25.5 lb. steam per horsepower-hour Rte LOWES 650 Oh ewe cecdine eet was 24.8 lb. per horsepower-hour. A table of comparative data taken from The Engi- neer, July 2, 1906, gives the following, which is based on the steam consumption per kilowatt at the switch- board : Compound. Simple. Single-valve. Four-valve. Aa ROMMEGAG sSe-binit's eateries aaah ome 55 1b. per kw. 47 lb. per kw. WE MOG Sb: d'e-e sis Ops 4 ace 0s ass 38 Ib. per kw. 42 Ib. per kw. Bull load. .........e+e-0+++ e304 ID. per kw. 401, lb. per kw. 1% loads........ TS eve cies oO AD POT RW: 41 lb. per kw. As already stated, the load is fairly constant in shop work, except during the lighting hours, and both of the above tests show that a compound engine may be oper- ated at 14% load without appreciable loss, and in fact the first test shows a slight gain. It so happens that the lighting and heating seasons come at the same time, so that any increase in the exhaust will be utilized in the heating system. Compound medium speed engines have an average steam consumption of 23 to 27 Ib. per i.hup., and com- pound Corliss from 22 to 26 lb. The water rate given in each case is for non-condensing engines. For con- densing engines the following give’ — results : 180 : THE IRON AGE July 15, 1909 Pounds. 100 ~- 0.85 = 118 hp. of electrical energy to be sup- Simple, medium. speed.......-.++--++e+eeeeee eeeeees * = “1 plied to the motors. , Ce es ean peearsrricrirurititin ss To 090118 + 0.90 = 181 hp. to be delivered by the engine for Compound engines are commonly built either tandem or cross-compound, the latter consisting of two com- plete machines attached to a common shaft and fly-wheel. The tandem is more compact, taking up but little more room than a simple engine; it has fewer parts and therefore requires less attention, both of which adapt it more especially to shop and factory work in the average sized plant. ; et Pumps.—Both steam and power pumps are used for boiler feeding. While the former are wasteful of steam, they have the advantage of being operated automatically or of being throttled down to a point where the speed is just sufficient for the needs at any time, while power pumps belted to the engine necessarily run at a constant speed and any regulation must be done by by-pass valves. Steam pumps are of two general types,* piston and plunger. The first is commonly used where the water is pure and free from grit, otherwise it is difficult to keep the piston tight and detect leaks when they occur. On this account the plunger pump is often preferred. Its plunger is easily reached and any wear is cared for py renewing the bushing in which the plunger slides. A plunger pump which may be packed from the outside is especially recommended for boiler feeding where the pressure is over 125 lb. per square inch. Size of Engines and Boilers. The power requirements of a machine shop include that for driving the machines and shafting and that for lighting. In addition to this the steam for heating m winter must be considered when computing the size of boilers. These power requirements may be indepen- dent or they may be more or less connected ; for example, the machines may be driven from shafting which in turn is driven directly by the engine, or they may be driven by individual motors supplied with current from a gen- erator driven by the engine, or power may be generated at a distance, either by steam or water, and transmitted in the form of electric current to the shop, where a single motor is used for driving the shafting. The light- ing may be done from the general supply or from an in- dependent outfit, and the heating may be either by ex- haust or live steam or by both. Owing to the various combinations which may exist in a single plant each power requirement will be traced back separately from motor to generator, engine and boiler. In this way any combination may be made up as desired. Where the combination of engine and shafting is used the first step is to determine the power necessary to drive all of the machines. Lists are available giving the approximate horsepower necessary for different ma- chine tools, from which the total can be determined with sufficient accuracy. To this about 10 per cent. should be added for shafting, &c. This total represents the horsepower to be delivered by the engine, and to find the indicated horsepower we must divide by 0.8 for well made engines under 100 hp. and by 0.9 for larger sizes. (These efficiencies will vary with different types and makes of engines, but the above are sufficiently accurate for approximate results.) Having determined the in- dicated horsepower of the engine, it should be multiplied by the probable water rate for the type used to deter- mine the weight of steam required per hour. This divided by 30 will give the boiler horsepower required. ELeample.—The combined machinery of a shop requires 100 hp. What will be the indicated horsepower of a simple noncondensing engine using 35 lb. of steam per indicated horsepower per hour? Also the boiler horse- power? ‘100 + 10 = 110 hp. for machinery and shafting. 110 + 0.9 = 122 = indicated horsepower of engine. 122 x 35 = 4270 Ib. of steam per hour. 4270 + 30 = 142 boiler horsepower. Where the machinery is driven by individual motors an average efficiency of 0.85 may be assumed for these motors, large and small; an efficiency of 0.90 for the dynamo and 0.90 for the engine. Taking the same ex- ample as before we have: running the dynamo. 131 + 0.90 = 145, the indicated horsepower of engine. (145 x 85) + 30 = 169 boiler horsepower. The economy of using individual motors is that whev a machine is shut down no power is required, while the usual arrangement of line shafting and loose pulleys must run constantly, regardless of the number of ma- chines in use at one time. If all of the machines were in constant operation the above example shows the shaft driven equipment to be the more economical. If the machines were used for heavy work, so that motors of ‘large size were required, it is likely that a higher effi- ciency could be counted upon; and again the arrange- ment of the shafting might be such that 10 per cent. would be too low for the power consumed in running it. In comparing the two methods of driving it is necessary to consider the cost of keeping the shafting, pulleys and belts in repair in comparision with the motors, as well as the actual power required. Again the item of danger from belts and pulleys and the improved appearance of the shop should be given due weight. When power is brought from a distance over trans- mission lines, and line shafting is used driven by a motor, losses in the generator, in transmission, in the motor and in the shafting must be considered. Taking the same example and assuming efficiencies of 0.90 for the generator, 10 per cent. loss in transmission, and the same loss through the shafting, what horsepower must be delivered to the generator? 100 + 10 = 110 hp. to be delivered by motor. 110 = 0.90 = 122 hp. delivered to motor. 122 + 0.80 = 135 hp. delivered by generator. 135 + 0.90 = 150 hp. delivered to generator. Lighting.—The power for lighting may be based on the number and type of lamps to be used, if this is known, * and if not, upon the space to be lighted. When the num- ber and type of lamp is known the following table may be used: Number of lamps supplied by 1 hp. of electrical energy at lamp terminals. Type and power of lamp. RUN a uleeWeile mke.e ba oat Nene oe ee 16 cp. incandescent. Sr eT ree re 82 cp. incandescent. Dia de en Soh ee oad Shapes teeree Half arc, open. Das Sb. 6 UR as oie SU ER IER Full are, open. DDR ow key a taies. «304 ane Closed arc. ‘Phe efficiency of a first class generating set (engine and dynamo), including the losses in transmission may be taken as about 75 per cent., when located in or near the building to be lighted, so that the electric horsepower necessary to supply the lamps, divided by 0.75 will give the indicated horsepower of the engine. From this the boiler power can be determined, as already described. Example.—What engine and boiler horsepower will be required to care for a lighting plant having 600 in- candescent lamps of 16 ¢c.p. each, and 300 of 32 c.p. and *20 closed arcs of the larger size? The engine is to be high speed, compound, noncondensing, using 28 Ib. of steam per indicated horsepower. From the above we have: 600 + 12 = 50 800 + 6 = 50 20 + 1= 20 120 This is the horsepower of electrical energy required of the dynamo, hence 120 + 0.75 = 160 = indicated horsepower of engine, and (160 x 28) + 30 = 149 = boiler horsepower. ; When the number of lamps is not given the lighting may be based on the floor space. For incandesceat lighting in offices and drafting rooms we may allow 1.8 watts per square foot of floor space for brilliant illumina- tion, and 1 watt for genera] or medium lighting. For are lighting the following may be used: ORNS. 5405 esa seeeeeeeeel.8 Watts per square foot floor space. Drafting room............ 2.1 watts per square foot floor space. Machine shop......... ... 0.74 watts per square foot floor space. Erecting room..... +++... .0.58 watts per square foot floor space. Having determined the total number of watts re- July 15, 1909 quired for lighting the kilowatt rating of the generator can be found by dividing by 1000. ‘The electrical energy in horsepower may be found by dividing the total num- ber of watts by 746 and the indicated horsepower of the engine by dividing the electrical horsepower by 0.75 (the efficiency of the generating set). Ezample.—Blectric lighting is to be provided for a manufacturing plant in which the floor space is divided as follows: : QO Sh EE ERNE Ole Peek lke eenaees 800 sq. ft. DEREAAR: TOS su shee e 6 kes eWS Tees Vet deen 1,000 sq. ft. IN BON ob a a ore 4c2 5-68 RRA de eS Odea Said Cer 15,000 sq. ft. SE UO oid aio 's 00s oid ob 6 GGG ER A RAR CAO EE Oe 10,000 sq. ft. The offices and drafting room are to be brilliantly lighted with incandescent lamps, and the shop and erect- ing room with are lights. What. will be the required size of generator, indicated horsepower of engine and boiler horsepower? Watts, NE Ee SeES Ee eR CON eee 800 X 1.8 = 1,440 Dratihies : LOCK 66558 66 8 i ML ied 1,000 X 1.8 = 1,800 Machine shop............. io bee ele ierealees 15,000 x 0.74 = 11,100 OCHRE. LOOT. Fock. kj. 0.54 acu eaeiman 10,000 x 0.53 = 5,300 ON ss 65K odes We oa sik ake Ck a Kn oe 19,640 Calling this 20,000 in round numbers we have: 20,000 -- 1,000 = 20 kw. generator. 20,000 746=—27ehp. 27 0.75 = 36 i.h.p. of engine. Assuming a high speed simple engine requiring 35 Ib. of steam per indicated horsepower the boiler horsepower will be (36 x 35) + 30 = 42, Feed Water Heaters.—The required amount of heat- ing surface depends upon the initial temperature of the feed water, the steam pressure within the heater and the velocity of the water within the tubes. With exhaust steam from noncondensing engines, it is customary to allow 1 sq. ft. of heating surface for about each 90 Ib. of water passed through the heater per hour. When exhaust steam from condensing engines is used the sur- face should be increased about 50 per cent., owing to the lower temperature of the steam. This calls for about 1-3 sq. ft. of heating surface per horsepower for noncon- densing engines and % sq. ft. for condensing. Condenser.—The size of the condenser, like the feed water heater, depends entirely upon local conditions, and in selecting it is usual to furnish the manufacturers with the necessary data and let them select the proper size. In determining the size it is necessary to know the weight of steam to be condensed per hour, the pressure in the condenser and the initial and final temperature of the cooling water. Assuming average conditions of 3 Ib. absolute pressure ip the condenser, and initial and final temperatures of 70 and 110 degrees, respectively, for the cooling water, it gives the following results, which may be useful in approximating the required size in any par- ticular case: Square feet of cooling surface in condenser per i.h.p. of engine. Steam per i.b.p. cf engine—-pounds per hour. DNs Se cadre tr sss CURT eee ob eer eenErers 27 DG iiinct vetickbiprabe Quad beds Curewes 82 OB 4 on sb e HaR ein dda 8 aes tae 38 Pumps.—The capacity of a given size of pump de- pends upon the speed at which it is run and the amount of slip or leakage past the piston and valves. A pump should be of such size that when running at its full . capacity the piston speed will not exceed about 75 ft. per min. The following table of boiler feed pumps is based on a slip of 80 per cent. and gives the capacity, both in pounds per hour and boiler horsepower which it will supply : 30 strokes 45 strokes 60 strokes per minute. per minute. per minute. Pounds Pounds Pounds Size of pump. perhour. Hp. perhour. Hp. perhour. Hp. 2 x1% x 2%.... 198 z 297 10 396 13 oS: 3 16 Shs. 720 24 1,080 36 1,440 48 4% x 2% x 4...... 2,316 77 3,474 116 4,632 154 54% x 3% x 5...... 4,800 160 7,200 240 9,600 320 e: 2¢ Pe. Ks 7,530 250 11,295 876 15,060 502 7% x 4% x 6...... 9,600 3820 14,400 480 19,200 640 The proportions given in the table are for moderate to high steam pressures. If it is desired in any special case to operate the pump at a pressure much less than 20 Ib., it should be provided with larger steam cylinders. THE IRON AGE 181 In designing a boiler plant it is best to use two pumps, each of such capacity that one of them running at a speed of 50 or 60 strokes per min. will deliver the maxi- mum quantity of water required under ordinary condi- tions. This makes easy work for the two running to- gether and allows a reserve pump in case of a breakdown. Increasing the Power ofa Plant, The logical way of increasing the power of a steam plant is to install additional or larger apparatus when the best economy of operation is considered. There are cases, however, where it may be desired to increase the power temporarily or for only a few hours a day; or perhaps the shop has outgrown the power plant and it is intended in a year or two to erect a new one. In the meantime it is desirable to increase the power of the present plant without installing new boilers or engines. The following gives some of the different ways of in- creasing the output of boiler and engines already in use. Some of these methods call for a corresponding loss in economy and should only be considered as temporary makeshifts, while others are along the line of permanent. improvement : ' Boilers —Among the ways of increasing the power of a boiler plant may be mentioned first of all, greater skill in firing and cleaner heating surfaces, both outside and inside; next the installation of a feed-water heater for utilizing the exhaust steam, if one is not already in use; economizers for saving a portion of the heat ordinarily passing up the chimney; the placing of pipes or tubes along the sides of the furnace, thus adding to the heating surface of the boiler, and increasing the amount of evaporation by the use of forced draft. The increase in power by the first of these methods will depend entirely upon present conditions and the improvement possible in firing and cleaning. Without going into probable results, it is safe to say that this is always the first point to be considered when more steam is called for, as it is in the line of both increase and economy of output. Computations show that about one-seventh of the steam evaporated by the boilers may be utilized in heat- ing the feed-water from 70 to 200 deg. This means that the boilers are relieved of this amount of work gnd therefore have just so much more capacity for making steam.. If the exhaust can all be used in the heating system there is no gain to be made during the winter months by this method, but the advantage during the time when heating is not required is sufficient to warrant the use of a heater in nearly every case. The effect of an economizer through which the hot gases pass on their way to the chimney is the same as adding to the heating surface of the boilers, although the additional surface cannot be rated on the same basis per square foot, owing to the reduced temperature of the gases to which it is exposed. The percentage of gain in power will depend on circumstances, but under average conditions will amount to about 12 per cent. In using an economizer for this purpose it is customary to provide from 4% to 5 sq. ft.,of heating surface for each boiler horsepower. When economizers are used simply to save fuel without increasing the power of the boilers it is not necessary to increase the strength of the draft, because less fuel is burned and hence less draft is required. But when it is desired to burn the same or even a greater amount of fuel, as when an increase in power is desired, it is usually necessary to increase the strength of the draft to overcome the effect of the added obstruction to the flow of the gases and their lower temperature by using a fan. Means for increasing the capacity of a boiler by addi- tional heating surface placed around the furnace are usually patented devices and are more or less effective according to their design. With mechanical draft the capacity of a boiler may be increased from 380 to 40 per cent. Forcing a boiler beyond a certain limit lowers its efficiency, but for short periods and for temporary requirements in special cases it is often more than offset by the reduced first cost . and the smaller operating expenses. The loss in economy due to forcing is partially offset in two ways; first a cheaper grade of fuel may be used than with a natural draft, and again a certain gain {n efficiency is obtained, Ha i { H i / Hy i 182 due principally to the deeper fires which may be carried with forced draft and to the more intimate contact of the air with the coal. The increased pressure forces the air into space between the fuel which could not be reached under a lesser draft, and as a greater proportion of the air is therefore involved in combustion the total quantity is reduced, resulting in a hotter fire and a greater radiation of heat to the boiler surfaces. Engines.—The power of an engine can be increased by raising the boiler pressure; by delaying the cut-off; by running at a higher rate of speed, and by using a con- denser. Before raising the boiler pressure to increase the power of an engine a careful inspection should be made of the boilers to see if they are able to safely carry the added pressure. Again, engine parts are designed for certain maximum loads, and it is always well to ascer- tain from the makers the limit of pressure which can be safely imposed upon them. Raising the initial pressu‘e above the normal for which an engine is designed pro- duces a waste of steam, because it increases the cylinder condensation somewhat, due to the higher temperature, and the terminal pressure is higher and more heat is lost in the exhaust. Here again the utilization of the exhaust steam for heating purposes is an important fac- tor to be considered. The following table gives the theoretical mean effec- tive and terminal pressures for an engine cutting off at one-fourth stroke, but with different initial pressures, and will be found useful for purposes of comparison, although actual results would vary somewhat on account of cylinder condensation, the effect of clearance, compres- sion, &c.: Initial pressure Mean effective Terminal pressure (gauge). pressure. (gauge). Oe See oe es Scivaceee Sis yeww as Soper oss s 9 re rears a ge UR Gh Victd’s s Hie waldelccs 11.5 400 6 SS ool ho 0a eed DE cso s Cea b> Sena ass 15 As the power of an engine at constant speed varies as the mean effective pressure