bluuebunny/crossref_metadata_2025 huggingface dataset:
A Thermal Study of Available Steam-Power-Plant Heat Cycles
Authors: Hendrickson G. A. , Vesselowsky S. T.
Published: February 2023

Turbine and plant heat rates obtainable in large modern power plants are compared over a wide range of the pressure-temperature-cycle realm. These results were estimated from heat balances based on typical expansion lines for 30,000-kw turbines, which size was deemed sufficiently representative to draw rather general conclusions regarding large units. Cost estimates are not included, but the results are given in a form readily adaptable to the needs of those making economic comparisons. To this end, plant heat rates are given for estimating the rate of use of fuel, and turbine heat rates with supplementary data for estimating the size, and hence the cost, of the various equipment in a plant. The difference between turbine and plant heat rates allows for auxiliary power in proportion to the cycle requirements, and for miscellaneous losses sufficient to give the expected annual average value of the plant heat rates. While the computations are purposely fitted to a particular type of turbine and plant, the results apply approximately to most of the modern central stations. Comparisons of the thermal efficiencies of practical cycles with corresponding Carnot efficiencies are used to point out the best direction for future efforts. It is concluded that regenerative-feed-heating plants with the highest practicable initial temperature offer the greatest promise, both for immediate use and for future development.
Supersaturated Steam
Authors: Yellott John I.
Published: February 2023

Supersaturation, or the failure of steam to condense when the saturated condition is reached in an expansion, has long been a matter of interest to engineers. This paper presents the account of an investigation of this phenomenon in which the principal objectives were the location of the Wilson line, which indicates the condition at which condensation actually occurs, and the measurement of the size of the drops which are formed when flowing steam condenses. Examination of the flow of low pressure steam through an illuminated nozzle fitted with a glass top revealed that the condensation process could be observed and that the pressure of the steam at the condensation point could be measured with the aid of a search tube. It was found that in a simple convergent-divergent nozzle condensation did not occur until the steam had reached the condition approximately represented by the 3.5 per cent moisture line on the Mollier chart. The droplets which formed at that condition were extremely minute, their radii being of the order of magnitude of 6.2 × 10−8 cm, and there was no evidence of growth during their passage through the nozzle. Additional experiments with nozzles of other designs led to the discovery that under certain conditions condensation could take place when the steam had reached the 2 per cent moisture condition, and that the droplets so formed grew rapidly from about 10.0 × 10−8 cm to about 6.0 × 10−5 cm in radius. It was concluded that supersaturation invariably occurred in the condensation of flowing steam, and that the superheated steam formula should be used to estimate the flow of saturated steam through nozzles.
Some New Experiments on Buckling of Thin-Wall Construction
Authors: Bridget F. J. , Jerome C. C. , Vosseller A. B.
Published: February 2023

The first section of this paper describes a series of tests of the strength of thin-walled cylinders under a combination of torsion and axial compression or tension. Curves are obtained showing the strength of each of the several types of cylinders tested, under all possible combinations of these loads. All the curves obtained seem to have the same general form and the results suggest the possibility of finding a simple law by means of which a designer could determine the buckling strength of a structure under any combination of shear and normal stress, if he knows its strength under pure shear and under pure compressive stress.

The second section describes tests made to investigate the independence of different possible types of buckling of a structure. A set of L-section struts, identical except for the widths of the sides, were tested in compression. With small widths the struts buckle as Euler columns but with the wider widths buckling of the sides, as plates hinged on three edges, occurs first. Great care was taken to eliminate the effect of initial eccentricities. The results check the well-known theories for these two types of buckling and indicate that, for practical purposes, the two types can be considered independently of each other. The results also illustrate how enormously the strength-weight ratio of thin wall construction may be affected by details of design.
High-Pressure-Steam and Binary Cycles as a Means of Improving Power-Station Efficiency
Authors: Gaffert Gustaf A.
Published: February 2023

The purpose of this paper is to explore the possibilities of the mercury-steam cycle. Experimental work on diphenyloxide leading to the construction of a Mollier chart is presented and the binary possibilities are developed. The properties of aluminum bromide and its binary-cycle possibilities together with a consideration of Dr. Koeneman’s zinc-ammonium-chloride binary cycle complete the discussion of binary cycles. Some cycles using steam alone at very high pressures are included as a basis of comparison and to point out that, in the steam cycle, the ultimate has not yet been reached.
The Design and Performance of an Axial-Flow Fan
Authors: Marks Lionel S. , Weske John R.
Published: February 2023

This paper deals with the design and performance of an axial-flow fan for comparatively high pressures. The design is based largely on extensive investigations of the air flow through a fan of well-known design which yielded certain constants. The procedure in design is sketched very briefly—it involves the use of both airfoil theory and circulation theory. Full details are given of the completed fan. The performance of this fan is shown in a series of graphs and is compared with that of the fan used for the preliminary investigations. The influence of the number and location of guide vanes was investigated. Diffuser action is also discussed. The noise emission was measured and was found to be considerably lower than that from the original fan. A relation between noise and fan performance is pointed out.
The Test Performance of Hudson Avenue’s Most Recent Steam-Generating Units
Authors: Hardie P. H. , Cooper W. S.
Published: February 2023

This paper presents the results of an acceptance test on one of the largest stokers in operation at the present time. The main purpose of the paper, however, is to illustrate the procedures developed for measuring those losses which are commonly allowed to appear in the unaccounted-for item of the energy balance. These losses are the hydrogen and hydrocarbon losses, and the carbon-monoxide loss which is in excess of that indicated by the conventional type of Orsat apparatus. Usually, part of the cinder loss appears in the “unaccounted-for” because it is seldom determined with the accuracy which the magnitude of this loss as determined from the method described would seem to warrant. The completeness with which the losses in the present test have been measured is evident from the low value obtained for the radiation and unaccounted-for item of the energy balance.

A high rate of combustion (75 lb per hr per sq ft) was carried for 48 hr at an efficiency of 77 per cent. The superheater produced approximately constant steam temperature over the full range of loads.
The Economics of Preheated Air for Stokers
Authors: Dillon Robert E. , Engle Melvin D.
Published: February 2023

The development of the regenerative cycle, the operation of boilers at higher and higher outputs, and the adoption of higher pressures and the single-pass boiler, have reduced the heat-reclaiming possibilities of the economizer and have resulted in the installation of air heaters for most high-efficiency steam-generating units.

Highly preheated air has increased the maintenance of underfeed stokers beyond reasonable figures.

The purpose of this paper is to determine to just what extent stoker maintenance is a function of air temperature.

Maintenance data have been supplied by 33 operating companies operating 122 underfeed stokers supplied with hot air. The data cover stokers operating with average air temperatures varying from 120 to 460 F and maximum air temperature as high as 600 F and representing 475 stoker-years of operation.

Maintenance has been plotted against average air temperature and a fairly satisfactory relation found. In order to remove the influence of other variables affecting maintenance, stoker maintenance has been plotted against other operating and design factors, and each corrected for temperature.

From this data it was found that the variables, other than average air temperature, which most seriously affect maintenance are:

(1) Area of stoker

(2) Average coal burned in lb per sq ft per hr

(3) Percentage of ash in the coal burned.

The data were corrected for these three variables, and a new curve of maintenance vs. average air temperature was obtained with some of the influence of these three variables removed.

From this corrected curve the following conclusion can be drawn: Up to 300 F, the preheating of the air supplied to underfeed stokers does not seem to increase maintenance above reasonable figures, but above 300 or 350 F, there is a sharp increase in maintenance with increase in air temperature.

Information is also given in the paper on the changes made and operating methods used by various companies to reduce stoker maintenance.

Data were also obtained on the maintenance costs of 77 chain-grate stokers supplied with hot air, representing 440 stoker-years of operation. When plotted, the data did not show any consistent relation between maintenance and average air temperature. However, a study of the data seems to indicate that chain-grate stokers, supplied with hot air and burning the types of fuel for which they are suited, can match the underfeed stoker in coal-burning capacity in lb per sq ft per hr, and apparently operate with lower maintenance costs.
The Elastic Properties of Steel at High Temperatures
Authors: Versé Guy
Published: February 2023

This paper deals with the determination of the modulus of elasticity and of the modulus of rigidity of steel at elevated temperatures up to 500 C.

Both a static and a dynamic method were used and their results are compared. Whereas previously most of the static determinations of these moduli have been made under increasing load, in the tests described in this paper they were determined under decreasing load, according to the method proposed by F. L. Everett. The tests show that within certain limits the results obtained by this method are practically independent of the rate of loading. This appears to be due to a strain-hardening effect occurring upon loading and detected upon unloading.

The comparison between the static and the dynamic tests shows that the values of E, modulus of elasticity, and G, modulus of rigidity, determined statically under decreasing load are close to the values obtained dynamically. However they are somewhat lower for temperatures above 400 C.

The values obtained for E and G by static tests under increasing load are not reliable owing to the difficulty of discriminating between the elastic and the plastic deformation.

The values determined dynamically are the most reliable.

The variation of Poisson’s ratio with temperature is also presented, the values of μ being obtained by calculation from the values found for E and G.
A New Basis for the Rating of Roller-Chain Drives
Authors: Bartlett G. M.
Published: February 2023

Reference tables giving horsepower ratings for roller transmission chains are commonly based upon certain allowable working pressures per square inch of projected bearing area at the chain joints. The allowable working load is assumed to increase in proportion to the projected area of the pins and to decrease with an increase in chain velocity and an increase in the “centrifugal pull” of the chain.

An analysis of the bending action of the links at both driving and driven wheels and the work of friction between pins and bushings yields an algebraic expression for the beat generated per minute, or for the rate of wear in the chain. This is proportional to the rate of elongation of the chain; and this rate of elongation is found to be directly proportional to the horsepower transmitted and inversely proportional to the pitch, the length of the bushing, the number of links in the chain, and the product of the number of teeth in the two sprockets (very nearly). A set of tables is developed based upon chain velocity and the number of teeth in both sprockets. The horsepowers taken from these tables are such as will produce approximately the same rate of elongation in all drives whose design and operation conform to average conditions. Similar tables are computed on the basis of the rpm of the smaller sprocket instead of the chain velocity.

These tables also allow for the extra pull on the chain due to centrifugal force, and for the chain lengths and center distances necessary to keep the rate of elongation within the limits allowed.

An examination of these tables shows that, with certain combinations of sprocket teeth and chain lengths, loads twice as great as those usually given in tables can be transmitted. And these figures seem to be supported by actual practice.

The subject of limiting speeds for sprockets is treated and three sets of limiting conditions are investigated, namely: (a) the effect of a single impact between chain rollers and sprocket teeth, (b) the energy of impact per tooth per minute, and (c) the effect of centrifugal action. A table is compiled giving maximum chain velocities and sprocket speeds, based upon these investigations, for various chains and various numbers of teeth in the sprockets. This table shows the conditions under which certain chains can be operated at velocities above 3000 fpm and other conditions under which the same chains should not be operated at more than 240 fpm.
Concerning the Degree of Accuracy of the Gibson Method of Measuring the Flow of Water
Authors: Thoma D.
Published: February 2023

The paper first discusses the limitations of various methods of measuring water which were in use when the Gibson method was first announced. These limitations of the current-meter method of flow measurement include: The effect of turbulent accessory motions which cause periodic velocity changes in the direction and magnitude of flow; the difficulty in obtaining readings close to the wall of the canal or closed conduit; and the necessity of determining the velocity at several points simultaneously due to temporary changes in distribution; and the expense involved in taking a number of such simultaneous readings. Reference is also made to the use of the pitot tube for taking readings close to the wall of the passage.

The greater part of the paper, devoted to a discussion of the Gibson method of water measurement, includes the derivation of formulas involved in this method of water measurement, its limits of accuracy, and the errors which may arise in its use. These errors, due to (a) accessory motions, (b) to false valuation of friction, (c) to friction of the mercury column, and (d) to inertia of the mercury column, are presented with derived formulas and approximate values together with suggestions for minimizing them.
Water Gaging for Low-Head Units of High Capacity
Authors: Mousson J. M.
Published: February 2023

In the field of hydroelectric construction there has been in recent years considerable advance in the development of low-head units of high specific speed. This tendency in design has been conducive to the development of low-head sites which were at one time considered uneconomical. It became, therefore, increasingly important to find methods of measuring the discharge of low-head plants where the water quantities are large and the water passages particularly short and unsuited to other methods of testing. American engineers had developed methods of measurement of flow in long penstocks and then attempted to extend these methods to plants with shorter water passages. European engineers have shown a preference for current meters, at one time commonly used on both sides of the Atlantic for measurements in large intakes.

The paper discusses the status of the current-meter method in Europe at the time this method was selected for the tests at Safe Harbor and the application of the two-type meter method. It shows how this method was applied at the outset and how certain modifications were made for increasing the reliability and decreasing the time and effort required for making tests. These made possible new methods of compilation which have been developed to facilitate greatly this phase of the testing program. The successful application of these methods should make current-meter measurements more feasible than ever before.

In preparation for these tests, investigations were conducted at the Bureau of Standards and elsewhere to determine the characteristics and limitations of the meters under various conditions of uniform, oblique, pulsating, and turbulent flow.

It has been shown that water passages with parallel sides for metering and approach sections do not insure parallel flow, and that even under as nearly ideal conditions as it is practical to secure, the use of two types of meters will indicate an effective angularity. However, it is believed that accurate measurements of oblique flow can be made by the use of two types of meters, each affected to a different extent by angularity. The use of this method will greatly enlarge the field of current-meter testing.

There are pointed out the advantages of making index tests in conjunction with current-meter measurements; not only to extend them to a wide range of operating conditions, but also as a measure of the consistency of the discharge measurements.
Draft-Gear Action in Long Trains
Authors: Wikander O. R.
Published: February 2023

This paper is a study of the coupler pressures, car speeds and accelerations in a long train, produced by external forces acting on same.

It is based on the similarity in behavior of such a train and of an elastic bar of the same length as the train, the same mass per unit length and the same yield, when subjected to longitudinal compressive or tensile forces.

Following the method explained in the paper, the pressure and speed diagrams are derived for the various periods through which the waves are passing, the beginning and ending of each period being marked by certain events. Formulas are derived for the maximum bar pressures and tensions, for the locations at which they occur, and for the maximum accelerations or retardations of the particles.

It is shown how these formulas may be applied to freight trains of known characteristics, and the general requirements are derived which should be met by a freight-car draft gear under given service conditions.

Well-known elementary calculations, based on the official ARA Draft Gear Tests and supplemented by the formulas given in the paper, permit the design of draft gears suitable for the given service conditions.
The Design and Performance of a High-Pressure Axial-Flow Fan
Authors: Marks Lionel S. , Flint Thomas
Published: February 2023

This paper deals with the design and performance of an eight-bladed axial-flow fan to give high pressures and an approximately constant horsepower characteristic. The performance in the laboratory indicates the attainment of a static pressure of 22.2 in. of water at a peak efficiency of 77.5 per cent, with a peripheral speed of 40,000 fpm. The no-flow horsepower is only 16 per cent greater than at peak efficiency. The performance is compared with that predictable from wind-tunnel tests of a cascaded series of air foils.
Progress in Cavitation Research at Princeton University
Authors: Moody Lewis F. , Sorenson Alfred E.
Published: February 2023

The authors describe test apparatus and an experimental method used to determine the critical point of cavitation, or cavitation limit, of liquids flowing in a closed system as caused by the formation of vapor-filled cavities in the system. The experiments here described were directed to determine the cavitation limit, at which cavitation begins, and not to ascertain the consequences of maintained cavitation. The authors show that the experiments give results entirely consistent with the cavitation principle as now generally applied.
Safe Operation of High-Speed Locomotives
Authors: Cain B. S.
Published: February 2023

In this paper are presented the basic theories, test information, and the chief conclusions of an investigation of factors entering into the mechanical design of locomotives for high-speed operation. The author points out that (1) recent trends in railroad operation have been toward higher speeds over longer distances and (2) the development of electric and oil-electric power, and lightweight equipment have changed many of the conditions under which these higher speeds are attained. In view of the radically new types of equipment available, the increased severity of requirements both as to performance and cost of equipment, and the necessity for preserving the railroad’s record for safety, it has been necessary to make an extended theoretical and experimental analysis of high-speed locomotive operation. Such an analysis is given in this paper.
Film-Lubrication Theory and Engine-Bearing Design
Authors: Dennison E. S.
Published: February 2023

In this paper the data of film-lubrication theory have been adapted to the purposes of bearing design for reciprocating engines, particularly for the case of the high-speed internal-combustion engine. Suitable corrections for end leakage in short bearings have been incorporated and the results are presented in the form of design charts. Some published experimental data have been correlated with reference to the theory. The flow of oil in pressure-fed engine bearings has also been treated, the oil being considered as a coolant as well as a lubricant. The paper includes a brief discussion of the application of the data in design, with remarks on some detail features and practices.
Locomotive and Car Journal Lubrication
Authors: Pearce E. S.
Published: February 2023

This paper discusses the economic significance of railroad-journal lubrication and reports on researches made on the causes of failure and development of remedies therefor as pertain to design, materials, and operating practices.
High-Temperature Properties of Cast and Wrought Carbon Steels From Large Valves for High-Temperature Service
Authors: Cross H. C. , Dahle F. B.
Published: February 2023

The authors report on a comparison made at temperatures of 750, 850, and 950 F of the short-time tension, impact, and creep properties of two forged and two cast carbon steels taken from finished valve bodies and tees obtained from the regular commercial run of three reputable manufacturers and made for service at elevated temperatures. Each manufacturer suppling the material gave it the heat-treatment normally used in his own plant for that particular type of material.

Two cast steels and one forged steel contained about 0.35 per cent carbon and one forged steel contained about 0.27 per cent carbon. Definite differences in structure were found. One cast steel as supplied by the manufacturer showed a spheroidized structure, while the other three steels were pearlitic.

Results of the creep tests are compared with the structures, and results of the short-time tension tests and impact tests at room and elevated temperatures are given.
Heat Transmission in Steel-Reheating Furnaces
Authors: Eberhardt J. E. , Hottel H. C.
Published: February 2023

In this paper the results of 23 tests on six continuous billet-reheating furnaces of widely varying size operating under widely varying conditions are presented and correlated by means of a relatively simple semiempirical equation suitable for use in design calculations. The equation giving the heat transmission involves the product of a fourth-power temperature function, the effective hearth area, the emissivity of the flame due to its nonluminous constituents, and the continuity of operation of the furnace. The use of the equation in design calculations is illustrated.

The second portion of the paper presents results of a more comprehensive test of one of the furnaces, including both terminal and intermediate conditions. The agreement between the results of tests on the various sections of the furnace and the heat transmission predicted from a rigorous consideration of the various contributing mechanisms is good. Since the method of attack outlined in this section is free from empiricism, its applicability is not limited to reheating furnaces.
Measurement of Gas Temperatures in an Internal-Combustion Engine
Authors: Hershey A. E.
Published: February 2023

The author summarizes the various methods used in determining gas temperatures in an internal-combustion engine, giving complete references to the various papers and reports published on the subject. The purpose of this discussion is to consider the various methods of determining gas temperatures in an engine during the combustion and expansion periods and to evaluate critically results of such determinations.
Estimation of Dissolved Solids in Boiler Water by Density Readings
Authors: Rummel J. K. , Holmes J. A.
Published: February 2023

This paper gives (a) a description of the instruments most generally used in determining the amount of dissolved solids in boiler feedwater, (b) the procedure for using these instruments, and (c) the results obtained with the instruments during tests of representative samples of boiler feedwater.
Operating Experience With Pulverized Texas Lignite in a Large Central Station
Authors: Hardy Norman G.
Published: February 2023

This paper describes the lignite resources of Texas, the characteristics of lignite, and the equipment, operating practices, and results obtained in burning it at the Trinidad steam-electric station, the base-load station for the Texas Power and Light Company, 65 miles southeast of Dallas. The station has six steam-generating units firing pulverized lignite, and two 20,000- and one 35,000-kw turbo-generators. The original plant, consisting of four steam-generating units, and two 20,000-kw turbines, started operation in June, 1926. The rest of the station started operation in May, 1931. Trinidad was not only the first large station to use Texas lignite, but also the first to use it in pulverized form. In the ten years of its operation it has used 100 per cent pulverized lignite very successfully in regard to reliability and economy. Operating costs have been favorable as compared with fuel oil and natural gas during a period when there has been a very large flush production of each within the state. It is now the only station burning pulverized Texas lignite and the only large station burning it in any form.
Distribution Costs
Authors: Knapp C. Howard
Published: February 2023

The author approaches the subject of distribution costs from the standpoint of what is actually being done with every item of the distribution cost in the case of one specific company. He shows the actual method used by that company in creating standards for the different elements of distribution costs, the application to the various products manufactured by that company, and the method used in applying such costs to the different territories.
New Laboratory Data Relative to Embrittlement in Steam Boilers
Authors: Straub F. G. , Bradbury T. A.
Published: February 2023

Results of laboratory tests show that purified sodium hydroxide will not produce cracking of steel test specimens in short-time tests, whereas technical sodium hydroxide made by the lime-soda process will produce cracking. When the impurities present in the technical sodium hydroxide are added to the purified caustic and then used in tests, the specimens crack. It appears that when silica is present in sufficient amounts along with the pure caustic, cracking will take place. However, when smaller amounts of silica and small amounts of calcium, magnesium, and aluminum are added to the pure caustic, cracking will also take place. These results indicate that it is apparently necessary to have one or more catalysts present in the sodium-hydroxide solution in order to cause cracking within a reasonable period of time.
Welding Design
Authors: Jennings Charles H.
Published: February 2023

Although welding has been extensively used in the fabrication of engineering structures for a number of years, there is still a decided lack of knowledge among engineers concerning the fundamental factors governing a satisfactory design. In addition, there is a lack of agreement among designers as to the methods of calculating weld stresses and the correct working stresses to employ for different types of joints. This article contains a discussion of a number of variables such as the selection of the proper joint, the calculation of weld stresses, the determination of working stresses and safety factors, and the important features governing a good welded design.

An analysis is made between butt and fillet welds in an effort to assist the designer in the selection of the proper type. Theoretical and practical aspects such as stress concentrations resulting from discontinuities in form, fabrication difficulties, welding costs, and distortion problems are considered.

The calculation of weld stresses in different types of joints is discussed and suitable formulas recommended on the basis of their agreement with test results, and their general applicability and acceptance in present design practice.

Working stresses and safety factors for butt and fillet welds are determined on the basis of static and dynamic tests. A table of recommended working stresses for bare and coated-electrode welds subjected to all types of loading is given to assist the designer. This table is based upon joints made on ordinary low-carbon structural steel.

A number of important design features that are essential in the design of economical welded structures are given. These features include the recommended minimum size of fillet welds for given plate thicknesses, the application of intermittent welds in design, and the influence of joint design on the economical fabrication of butt joints.

An appendix is attached which contains a number of typical welded-joint designs with the corresponding recommended formulas for calculating the stresses.
Casting or Welding in Machine Design
Authors: Brown J. L.
Published: February 2023

This paper is a presentation of the problems involved in choosing between a cast machine part or a part fabricated by welding for any specific purpose. The author discusses the advantages and disadvantages of each method in the light of cost, utility and appearance of the finished product and compares the casting method with fabrication by welding for several specific structures. Fields in which fabrication by welding can and cannot compete with castings are also mentioned, together with problems involved in designing a welded part to replace a casting.
American Hydraulic-Laboratory Practice
Authors: Hooper Leslie J.
Published: February 2023

It is the purpose of this paper to describe briefly representative American hydraulic laboratories and their work in recent years. Laboratories in this country and Canada were visited by the author during 1934 and 1935 as a Freeman scholar. It was obviously impossible for the author to visit every laboratory in this country in the time allotted and just as impossible to adequately describe each laboratory. Hence, considerable detail must be omitted in this article and many laboratories will not receive the attention their work deserves. Such omissions are not intentional but due only to the limitations of time available for inspection and space available for this paper.
A Theory of Paper Drying
Authors: Cowan E. , Cowan B.
Published: February 2023

The authors develop theoretical formulas for predicting the performance of paper-drying machines and compare the results obtained by using these formulas with representative machines now in use. The paper includes a discussion of (1) the problems met with in the paper-making industry and how these problems can be dealt with theoretically in an effort to predict the performance of drying machines and (2) fundamental equations which can be used in designing and perfecting new equipment.
Modified I.S.A. Orifice With Free Discharge
Authors: O’Brien M. P. , Folsom R. G.
Published: February 2023

The authors present results obtained with a modified type of International Standard Orifice as used for metering pump discharges. The annular slot for pressure measurement of the standard I.S.A. orifice is replaced in the modified orifice by a series of slots at the pipe wall and flush with the orifice plate. The results given in the paper include coefficients obtained with sharp-edged and rounded-edged orifices with various orifice-pipe diameter ratios and with various approach lengths of pipe. The coefficients obtained by the authors with the modified I.S.A. orifice are compared with coefficients of the standard I.S.A. orifice.
Cemented Carbide-Fitted Saws and Woodworking Knives
Authors: Thompson C. M.
Published: February 2023

The author reviews the development of the present design of carbide-fitted saws and gives some standard tooth angles required for various materials. Certain recommendations are made for the application of cemented carbides to woodworking knives and for the operation of carbide-fitted saws and knives on wood. Savings effected by the use of Carboloy saws are tabulated by the author.
The Prevention of Failures of Surface-Condenser Tubes
Authors: Dillon R. E. , Eaton G. C. , Peters H.
Published: February 2023

This paper describes the developments in the prevention of failures of surface-condenser tubes in the steam-electric generating stations of The Edison Electric Illuminating Company of Boston. The authors apply the latest theories of destructive cavitation to show that the inlet-end wastage of tubes in a single-pass condenser is the result of vortices in the inlet water box. These vortices result in destructive cavitation which starts when the water pressure at a point approaches the pressure corresponding to the water temperature, and the cavities in the water are filled with vapor. When the existence condition for the vapor disappears through increase of pressure, the vapor bubbles condense and very high impacts on adjacent surfaces result. Tiny particles are broken from the surface by repeated impacts, making larger and larger pits, and eventually holes through the tube are produced. Guide vanes installed in the inlet water box of the condenser have effectively prevented the vortices from forming.
Incinerators—Municipal, Industrial, and Domestic
Authors: Hersey H. S.
Published: February 2023

The author reviews briefly the historical development of incinerator plants and discusses the trends in design in this country and abroad. Although industrial-waste incineration is mentioned briefly, and the incineration of domestic and institutional wastes is discussed in some detail, the greater part of the paper is devoted to the incineration of municipal wastes. Many problems and conditions governing steam production in incinerator plants are touched upon, together with general rules for estimating required incinerator-plant capacity in American communities. The author discusses in detail the design of municipal plants with complementary or auxiliary equipment employed. The latter part of the paper is devoted to the utilization of garbage and rubbish as fuel, with examples pertaining to furnace heat balance and furnace temperature.
The Springwells Station of the Detroit Department of Water Supply
Authors: Rudd William C. , Mullen Bernard J.
Published: February 2023

The Board of Water Commissioners of the City of Detroit anticipated the need of increasing the water-supply facilities for the city nearly 20 years ago and in the year 1919 ordered that engineering studies be made. As a result of these studies an additional water-supply system was authorized in 1924 at an estimated cost of $30,000,000. The project included a new river intake of 940 million gallons daily capacity, tunnels in sizes of 12 ft to 15½ ft diameter, about 12 miles long, a new pumping plant for 400 million gallons daily, filtration plant, and 16,500-kw steam-operated power plant. The new works were substantially completed in 1931 and placed in partial operation, but due to the depression, the plant was not placed in continuous service until 1935.

This paper discusses the various problems and engineering studies made in connection with the design and construction of a large modern water-works plant, with especial reference to the hydraulic and mechanical features of the pumping plant and the mechanical and electrical characteristics of the steam-operated power plant.

The pumping plant consists of raw-water pumps for delivering river water from the intake and tunnel system to the filter plant and also the filtered-water pumps to force water supply to the city distribution system. All pumps are housed in one building about 400 ft long by 100 ft wide. There are 26 centrifugal pumps varying in size from 7 to 60 million gallons daily each. The pumps are driven by synchronous and induction motors.

Power for the pump motors is produced in a steam turbogenerator plant, exclusive of a small portion that is secured from a central-station source. The power plant is adjacent to the pumping plant and consists of two 5000-kw and three 500-kw steam turbogenerators, two 90,000-lb per hr steam boilers and related equipment, together with a 5000-kw transformer for central-station power.

This paper deals with purchase of pumping and power-plant equipment secured in competitive bidding, with some of the major equipment secured on evaluated bids and with bonuses and penalties applied to contractor’s guarantees. The paper also outlines the results of field acceptance tests for pumps, turbines, and boilers and gives the resulting bonuses and penalties applied to the various contracts. The paper also discusses the general plant-operating economies for a one-year period.
Experiments and Calculations on the Resurge Phase of Water Hammer
Authors: LeConte Joseph N.
Published: February 2023

The author develops a theoretical expression for the multiple recoil or resurge effect of a long water column following the instantaneous, or approximately instantaneous, closing of a valve at the lower end of the column. The time period between successive resurges or hammer blows is calculated by the developed expression and is compared with time periods recorded from tests by an oscillograph. The computed and observed results are presented in tabular and graphical form for several of the tests.
The Application of Heaviside’s Operational Calculus to the Solution of Problems In Water Hammer
Authors: Wood F. M.
Published: February 2023

The author points out that Heaviside’s operational calculus, which has been used extensively in connection with electrical surges in transmission lines, may be used in the study of water hammer even though certain limitations are involved because of necessary approximations which must be made when applying it to hydraulics. In spite of these limitations, the method is useful in clarifying many surge problems, verifying some truths which have been established by other methods. It is not the purpose of this paper to attempt to cover the entire field of surge problems, but to introduce Heaviside’s operational calculus in the field of hydraulics for the study of water hammer.
The Friction of Reciprocating Engines
Authors: Dutcher F. H.
Published: February 2023

The author presents graphically the trend of friction-speed-load relations in reciprocating engines from 1878 to the present date, using representative data from the literature. He discusses some of the variables which affect the friction of a reciprocating engine, and mentions some of the methods for determining friction losses.

The paper contains a description of an automotive-engine and cradle-dynamometer setup used in tests for ascertaining the following relations: (a) Pumping losses versus rpm for different manifold pressures, (b) total friction mean pressure (pumping plus mechanical) versus rpm at different manifold pressures, (c) total friction mean pressure versus mean pressure on the pistons at different constant speeds, (d) mechanical friction mean pressure versus rpm at different manifold pressures, (e) mechanical friction mean pressure versus mean pressure on the pistons at different constant speeds. These relations are all presented graphically.
Locomotive Axle Testing
Authors: Buckwalter T. V. , Horger O. J. , Sanders W. C.
Published: February 2023

The general weakness of axles is within the region of the wheel fit near the inside hub face where axle fatigue fractures occur in service. This paper presents data from laboratory fatigue tests of full-size 11½-in. diameter driving axles to investigate such failures. A description and discussion of the suitability of the present design of axle-testing machine is submitted to indicate the reliability of the data obtained from this type of accelerated axle test for use in the design of railroad axles.

These axles show fatigue cracks developing at such low nominally calculated bending stresses as 10,500 lb per sq in. The propagation of fatigue cracks is considerably retarded by rolling the axle wheel seat. Without rolling, the axle breaks off in 5¾ million revolutions (20,500 equivalent miles) at 19,000 lb per sq in., whereas, tested at the same stress, a similar axle, except rolled at the wheel seat, operated 25 times as long (144 million revolutions or 510,000 equivalent miles) with development of a crack 7/16 in. deep.

Rolled axles compared with unrolled axles show little improved resistance to the development of incipient fatigue cracks as produced by a large number of repetitions of low stresses obtained under ordinary railroad operating conditions of speed and load. Under prevailing conditions of high speeds and load, however, the occasional stresses are considerably increased and cause these incipient fatigue cracks to propagate to breaking off of the axle. In this respect, rolling provides immense increase in resistance to these high occasional stresses to retard the crack propagation, thus giving greater safety.

A correlation of the 11½-in. and the 2-in. axle tests is given.
Trends in Fuel-Burning Equipment and Furnace Design as Shown by Recent Eastern-Seaboard Applications
Authors: Booth Ralph D.
Published: February 2023

By reviewing the steam-generator installations made during the last five years in eastern-seaboard industrial plants, it is the purpose of the author in this paper to determine trends in the design of furnaces and fuel-burning equipment. The subject matter is divided into three general parts: (a) A brief summary of the apparent trends in kinds of fuel, fuel-burning equipment, and furnaces; (b) a more detailed examination of the characteristics of representative installations; and (c) a summary of comments and suggestions with respect to future design.
Operating Methods and Problems of a Combined Hydro- and Steam-Electric System
Authors: Harrington H. L. , Strowger E. B.
Published: February 2023

Today a combined hydro- and steam-electric system requires the use of operating methods based upon the principles of economic loading together with satisfactory and reliable service to all customers, and it is essential to arrange for some plan of centralized supervision of the power-supply facilities in order to put these methods into effect.

Certain system changes, such as the proper interconnections of generating facilities and load areas will in general be required to make such a plan effective and, if input-output data regarding the hydro- and steam-generating facilities are not available, tests should be carried out to furnish this information for the load supervisors and plant operating personnel.

Further, maximum use should be obtained from all storage reservoirs, reserve-capacity requirements should be established on a system basis with the highest degree of service reliability reasonably possible, and satisfactory standards and methods for the maintenance of system frequency and voltage must be followed.
Theory of Resonance in Pressure Conduits
Authors: Jaeger Charles
Published: February 2023

This paper represents one of the contributions to the Second Symposium on Water Hammer and deals with the analysis of critical conditions in pipe lines where initial surges are augmented by the characteristics of the conduit. The paper is the first treatment in English of this subject, and should prove a valuable contribution to the knowledge of water hammer.
Condenser Performance With Reduced Cooling Surface
Authors: Harlow J. H. , Bowman R. A.
Published: February 2023

The authors discuss changes made in two condensers of 50,000 sq ft heat-absorbing surface, which changes provided steam lanes in the tube nests in an attempt to increase the effectiveness of the condenser surface. The heat-absorbing surface in the first condenser was reduced 20 per cent, while that in the second condenser was reduced 30 per cent. The authors present drawings showing the changes made, and explain the reasons for making them. Performance data on both condensers, before and after the changes were made, are presented in both graphical and tabular form.
Rollcurve Gears
Authors: Golber H. E.
Published: February 2023

In automatic machinery the movements of the various bodies are usually obtained from the motion of a follower compelled by a driver. The driver is usually assumed to rotate at a uniform speed and the follower is given some definite motion, ordinarily a definite rotation. When the follower motion is to be a rotation at uniform speed, the driver and follower are usually connected by ordinary circular gears. When the follower motion is to be a rotation of nonuniform speed, elliptical gears are sometimes used. When the follower is to move in a more complicated manner, all kinds of devices, such as cams or planetary levers, are used. Very frequently the designer does not know of any means for producing the desired follower motion. Therefore, he is compelled to use an undesirable motion which he knows how to produce, and abandons what he considers the best.

This article discusses rollcurve gears. It shows that by using such gears, the follower can be given practically any desired motion, thereby enabling the designer to produce the follower motion desired and obtain the best condition in the new machine. The article first illustrates actual rollcurve gears installed and in use on actual machines. It discusses their durability and applicability, and gives a short history of some of them. This is to assure anyone that these gears are reliable and that their production is practical.

The article next shows the production of the “speedgraf,” which is a standard method developed by the author to make the desired method perfectly definite. It is then shown how to convert the speedgraf into rollcurves which may then be drawn and tested on the drawing board. The rollcurves can then be used to obtain patterns for the gear blanks. These gear blanks then have the teeth cut into them, converting them into a pair of gears. When the driver moves at uniform speed, the follower moves in the desired motion. The result is positive and reliable.

Certain features that occur in connection with the rollcurve gears are explained. Also, to show the broad applicability of the gears, a few speedgrafs, for which gears have already been made, are shown and are commented upon.