bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving Drafting Management
Authors: Newbury F. D.
Published: April 2023

A system of improvement in drafting management extending over four years of experience is described, the use of these methods having cut drafting costs in half, while average salary rates have been increased, design quality has been improved, and drafting accuracy has been maintained. A feature of the plan is that each draftsman checks his own work, this resulting in increased responsibility and improved accuracy. Record charts showing the results attained are given.
Preloaded Ball Bearings as Applied to Machine-Tool Spindles
Authors: Brunner H. E.
Published: April 2023

In attaining precision of operation of machines fitted with ball bearings, after all initial looseness had been removed and dimensional tolerances held to very close limits, it was found that another factor remained which prevented attaining the high degree of accuracy of dimension and finish required of precision machine tools. This was that elastic deformation in the ball bearing had a great effect on quality. The cure was effected by preloading, this initial loading serving to remove all looseness between the balls and the raceways, as well as the more objectionable effects of early deformation that develops in a ball bearing under load. The proper value of the preload can be determined only after full consideration of the work loads involved.
Correlation of Casting Design and Foundry Practice
Authors: Taub Alex
Published: April 2023

Correlation of design and foundry is a necessary part of any sound engineering program. However, it is quite often neglected, adversely affecting the ratio of the result per dollar. In considering the foundry the fact that individual foundry practices vary must be borne in mind. Castings are virtually assembled in the liquid state within the mold, and this principle must be borne in mind, but not overdone. Open-mindedness on the part of the designer is essential. Foundrymen must be urged to express new foundry ideas, since in new designs provision might be made to permit the use of new foundry development. Machine-made green-sand coring is a new practice being successfully used. The true bulk of a design is in the flask, not in the individual casting. Wall thickness is a general target on weight reduction. This is bad practice. Weight must be eliminated by design. The designer can help in obtaining clean castings by providing ample space for cores. Driers are a necessary evil, and the design should eliminate them wherever possible. Elimination of fins still requires development on the part of the foundry. A large proportion of foundry and engine-operation difficulties can be traced to improper determination of engine length quite often by a non-technical executive. Impatience on the part of engineers to see their designs in operation results in insufficient time for the foundry to gain necessary experience with experimental castings. Cost items accrued during productive periods should be investigated and eliminated from any new design. Elimination of foundry difficulties also means elimination of trouble to the ultimate owner. Therefore the foundryman and engineer are equally interested in the final result.
Life of Tools Machining Free-Cutting Brass
Authors: Spence L. D. , Hall J. A.
Published: April 2023

The authors present a considerable amount of data on the life of tools under shop conditions machining free-cutting brass in automatic screw-machines. The analysis of this data shows that larger feeds and higher cutting speeds than those used in current practice can be combined with a reasonable tool life. The type of relation existing between cutting speed, feed, and life of tool found by Frederick W. Taylor and others for rough-turning of steel does not fit these tests of forming and drilling free-cutting brass. Within the limits of these tests an increase of the cutting speed is accompanied by greater economy. When machining free-cutting brass with ground circular-form tools, the life of the cutting tool between grinds appears to be nearly independent of the feed and of the cutting speed, and to depend primarily on the linear distance the work moves in contact with the tool. This indicates that the wear is primarily a lapping action, which is influenced more by the amount of movement of the edge of the tool against the work than by the pressure between them. Within the limits of the tests the maximum economy in machining free-cutting brass is secured by using the largest feed that the work and tools will stand and by running the stock at the highest spindle speed available.
Welding Progress at the A. O. Smith Plant
Authors: Jasper T. McLean
Published: April 2023

This paper covers the history of welding of pressure vessels in one plant covering a period of one-third of a century. The oil industry is credited with having provided the opportunity for the rapid development of welding, not being limited by code restrictions as to the size and shape of desired pressure equipment. Testing equipment is described, and tests on steel for pressure vessels are detailed.
Analysis of Stresses in Sucker-Rod Joints
Authors: Kemler Emory
Published: April 2023

A recent analysis of oil-field pumping production showed that 25 per cent of the lost production was caused by sucker-rod troubles. Much research has been attempted to determine the loads carried by the rods, but heretofore no attention has been given to the stress condition existing in the sucker-rod joint. These joint failures amount to 72 per cent of sucker-rod failures. As the sucker-rod joint is the largest individual trouble maker in pumping operations, the purpose of the paper is to determine the magnitude and distribution of load in the joint and to discuss methods of studying the problem.
Design and Investigation of a Spring in Which All Coils Nest Simultaneously
Authors: Reynolds J. B. , Schier O. B.
Published: April 2023

The purpose of this study was to design a spring of constant slope, the lower coils of which would not nest until loads larger than those causing corresponding coils to nest in constant pitch springs were placed on the spring. The results obtained when the spring of constant slope was compared with one of constant pitch made it seem desirable to try to design a spring in which all coils would nest simultaneously. Work with this spring and with those previously investigated leads to the conviction that end effects considerably influence the amount of deflection. This spring, having a complete dead coil at each end, must be somewhat affected by this influence, though no experiments have been made to determine how much. The result of this influence would be that the experimental deflections would be greater than the theoretical, which agrees with the results found.
Design and Investigation of Conical Springs With Coils of a Constant Slope
Authors: Reynolds J. B. , Schier O. B.
Published: April 2023

The development of design and the investigation of the characteristics of conical springs with coils of constant slope rather than constant pitch are presented, and also the paper compares the actual performance of these springs with those of constant pitch as well as with the theoretical performance. The conclusions drawn from the investigation are: It is possible with existing formulas to predict the behavior of conical springs. For chrome-vanadium steel of the analysis given, the best heat treatment is to normalize at 1600 F, cool in air, quench at 1550 F in oil, and temper at 900 F in air. Conical springs of constant slope behave more like helical springs than do conical springs of constant pitch as regards load-deflection characteristics.
Merits and Applications of Animal Glue to Veneer Work
Authors: Jones Wilbur L.
Published: April 2023

The growing use of crotch, burl, and stump veneers has added to the technical difficulties of fine-furniture manufacturing. Animal glue, for manufacturing fancy veneered work, has properties commending it to the plywood maker, such as (1) its fluidity, giving a moderately large spread in highly concentrated solution; (2) its neutral reaction and chemical inertness, which make it incapable of staining delicate face veneers; and (3) its quick-setting and fast-drying tendencies, which permit prompt pressing. Modern processes of sizing and gluing are described. The veneering operation is analyzed from the standpoint of (1) the large area of wood surface to be covered with glue, (2) the large proportionate amount of moisture absorbed by the wood from the glue, (3) the short distance from the glue line to the surface to be finished, (4) the comparatively long assembly time, (5) the emphasis on beauty of appearance in the fabricated article, (6) the need for speed of production, and (7) the importance of quick and proper drying. The conclusion is reached that animal glue has kept pace with the industry and is well qualified for the highly decorative, if somewhat difficult, veneering processes of today.
Aluminum Oxide Versus Garnet as a Wood Abrasive
Authors: Traendly J. F.
Published: April 2023

A comparison is made of aluminum oxide and garnet as surface-coated abrasives in woodworking. Garnet as found in the native state breaks into wedge-shaped pieces that when cemented to a surface of paper or cloth continue to fracture so as to produce further sharp edges. Aluminum oxide is a manufactured product, made in the electrochemical furnace by fusing bauxite and adding coke and iron. The hardness, toughness, and fracture of the two abrasive materials are compared. A table is given that covers time-study tests of belts used in a woodworking plant, with the labor and material costs.
Pressure in Airships
Authors: Klikoff W. A.
Published: April 2023

The use of pressure in the so-called “pressure airships” and the methods used for maintenance of pressure are described. The effects of “gas head” and of excess internal pressures are considered as design factors, showing the advantages derived from a strength standpoint. It is pointed out that, by utilizing the pressure, the low factors of safety used by airship designers for critical loading conditions can be eliminated, and the ultimate design of the pressure rigid airship is discussed. Recognizing the disadvantages of manual control of pressure employed in the present airships, it is emphasized that pressure control can be made perfectly automatic if pressure regulators used in the modern power-plant installations are adopted for airship-pressure control. The proposed pressure-control system for large metalclad airships is described. To utilize the advantages of pressure as a design factor, the materials used in the present rigid airships should be more efficiently disposed around the cross-section, again pointing to ultimate metalclad design.
Combustion Processes in Aircraft Engines
Authors: Cummings H. K.
Published: April 2023

This paper presents three general types of combustion which occur in homogeneous mixtures of explosive gases (preflame oxidation, normal burning, and the explosive wave) and reviews available experimental evidence as to the combustion processes which actually occur in spark-ignition engines. Oxidation is detected optically by changes in absorption spectra and chemically by analysis of samples removed from the combustion chamber. The progress of flame away from the spark plug has been followed by visual, photographic, and electrical means, with simultaneous measurements of pressure development. Spectra of visible radiation and measurements of infra-red radiation, obtained through windows in the cylinder head, assist in analyzing combustion phenomena. The characteristics of preignition and knock are understood, but the exact mechanism of knock remains obscure.
Stainless Steel in Aircraft Construction
Authors: Ragsdale E. J. W.
Published: April 2023

Stainless steel will assume its position in the aircraft industry when and where the urge is strong enough to study its possibilities, to acquire its technique, and to overcome the discouragement of first efforts. The first use of stainless steel in aircraft was in England. Tons of it were used in the construction of the “R-101.” In this country a trend toward stainless steel is noted, particularly for air-transport units.
National Air-Tour Formulas and Other Methods of Handicapping
Authors: Altman P.
Published: April 2023

Methods of scoring and handicap used in aircraft competition events are given. The first part contains a historical review, and the second contains criticism of handicap formulas, these having a bearing on aircraft design and the improvement of airplanes. In many cases airplanes are especially designed for air races, and if the design is good, it increases progress. The paper takes up the important formulas for handicapping and considers them from a race and design point of view. Useful curves are plotted.
Mechanical Equipment for Handling Large Rigid Airships
Authors: Bolster C. M.
Published: April 2023

The paper describes the development of the equipment used at the Naval Air Station at Lakehurst, N. J., for docking and undocking the U. S. S. Akron. The main feature of the plan is a stern handling beam or long horizontal girder lying athwartship beneath the stern of the airship, holding the ship from each side with a cable system from heavy trucks moving along outward-lying tracks, and a floating support resting on a castoring taxying wheel and placed under the reinforced lower fin. This stern handling beam moves out of the hangar following the mobile mast to which the airship is moored. When a circular track is reached, the airship is positioned in the proper wind direction.
British Practice in Steam-Turbine Design
Authors: Gardner F. W.
Published: April 2023

This paper reviews considerations affecting steam-turbine development in England. Turbines of the size and type required for the larger central stations are covered, although description of some of the smaller plants has been included. In discussing steam conditions, attention has been confined to general tendencies. Developments in turbine practice have been influenced by the plan to link up all the power stations by an interconnecting network of transmission lines. To cope with the increased demand, new large power stations will be constructed, which will have the advantage of high load factors and favorable conditions for base-load running. Illustrations are given of types of turbines and equipment.
Economic Balance Between Steam and Hydro Capacity
Authors: Irwin K. McH. , Justin Joel D.
Published: April 2023

There is a popular fallacy that hydroelectric development and additional steam-plant generating facilities are competitive sources of power. Balancing one against the other is often discussed by engineers who are prejudiced in favor of hydro or of steam. It is the object of this paper to point out that each proposed hydro development should not be measured against an equivalent steam installation as a sole source of power, but that it is necessary to forecast the characteristics of the particular system in which additional capacity is required and to determine for the particular conditions whether the addition of steam or hydro will give the lowest total cost of power supply for the system.
Performance of Modern Steam-Generating Units
Authors: Hirshfeld C. F. , Moran G. U.
Published: April 2023

This paper is the final report on a study made of the performance of 250 large steam boilers over a period of three years. The results of the first year’s study were reported at the 1929 Annual Meeting of the A.S.M.E., and a summary of the full three-year period was presented at the 1931 Annual Meeting. The study was requested by the Central Station Power Committee of the Power Division. The primary object was to study boiler outages and their causes and the effect of such factors as severity of use, design, fuels, and methods of firing on boiler reliability, in the hope that a yardstick might be obtained by which the individual operator could measure the performance of his own units and predict the probable availability of new designs. The data obtained from each unit are presented, together with some comparisons of types and classes of unit. There also is a discussion of primary causes of boiler shutdown, which has not appeared in either of the previous papers.
A Study of the Data on the Flow of Fluids in Pipes
Authors: Kemler Emory
Published: April 2023

It was not until 1883, when Reynolds by dimensional analysis developed the equations for dimensional homogeneity and dynamic similarity, that any scientific basis for analyzing the experimental data on the flow of fluids was available. In view of the fact that only a small part of the experimental work previous to that of Stanton and Pannell has been reduced to Reynolds’ dimensional basis, it was deemed desirable to undertake the present investigation in order to get a more complete knowledge of the flow problem, and in it an attempt was made to obtain all the data available on flow in pipes under pressure.

Some of the more important conclusions to be drawn from the data presented are:

1 The friction factor is independent of the fluid flowing for the same values of the Reynolds number R.

2 The friction factor for drawn brass pipe varies only ± 5 per cent from an average value and is substantially independent of the pipe size and fluid flowing for the same value of R within the range encountered in practice.

3 The friction factor for new steel pipe varies with the size, and varies about ± 10 per cent from an average value.

4 The data on used and artificially roughened pipes show that if the roughness is not large enough to cause contraction and enlargement losses, the friction factor never exceeds the value 0.054.

5 The mean hydraulic radius can be safely used as a criterion only in the turbulent region.

6 Special care should be taken in the selection or determination of the diameter.
Ten Years’ Progress in Management, 1923-1932
Authors: Alford Leon P.
Published: April 2023

Industrial management has undergone a severe test in the decade 1923–1932 due to violent fluctuations in industrial activity and sharp contrasts in the results of operating performance. Despite these changes it has made steady progress. It has been extended to all human activities where work is done. It has contributed to the accelerated rate of industrial development of the first six years, and its principles and practices have withstood the decisive trial of the deep depression of the last three. As an outcome of its application, well-managed concerns have passed through this period of business recession better than all others; as a result of its progress, management is now firmly established as a function in industrial operation. An examination of the changes in trends of some 25 industrial-management developments supports this major finding.
Spray Characteristics of a Jerk-Pump Fuel-Injection System
Authors: Zahn O. F.
Published: April 2023

Tests were conducted with special spray-research apparatus in the Oil Spray Laboratory at Pennsylvania State College, aided by the loan of jerk-pump injection equipment. The application of the conclusions reached is summarized as follows: Variables that could be changed in engine installation are speed, load, and nozzle-opening pressure. These would affect the combustion line on the indicator card only as they changed temperature, turbulence, and spray characteristics. Within the range tested of these operating variables, only opening pressure would change spray characteristics enough to produce a notable effect on the combustion. It would also limit the minimum load that the engine could carry. The effects of speed and load on the spray would be negligible compared to their effects on temperature and turbulence. Combustion would be practically free from the effects of changing spray characteristics with a constant nozzle-opening pressure.
Some Problems in the Lubrication of Vertical Journal Bearings
Authors: Ponomareff A. I. , Howe E. D.
Published: April 2023

In deep-well pumping a motor at the surface drives a pump runner at the water level through a long vertical shaft supported at the top by a thrust bearing and guided at intervals of its length by journal bearings. For effective design the power absorbed by the journal bearings should be known approximately. The preponderance of horizontal shafts in various kinds of machinery has resulted in an extensive literature on their lubrication, but there is little that bears on the lubrication of such vertical shafts as are used in pumps, hydraulic turbines, a few steam turbines, cream separators, and centrifuges. The friction loss in these is small, but in the deep-well pump the loss may be as great as 5 per cent of the power input. The paper relates the details of an investigation to establish some of the basic facts underlying the lubrication of vertical journal bearings such as are used in deep-well pumps.
Strength of Roll Necks: Report of the Special Research Committee on Heavy-Duty Anti-Friction Bearings
Authors: Trinks W. , Hitchcock J. H.
Published: April 2023

The increasing use of anti-friction bearings for roll necks, which frequently necessitates a change in the customary proportions of roll body and roll neck, has made the question of roll-neck strength an important one. At the juncture between roll neck and roll body, stresses of high intensity occur which cannot be evaluated by the familiar formula of mechanics, and regarding which few directly applicable data were available. In order to evaluate the concentration of stress at this point, and to indicate the manner in which the stress concentration is affected by varying proportions of roll body, and roll neck, rupture tests were made with model rolls of gypsum plaster, having various proportions and several different sizes and shapes of fillet. The test conditions were made to correspond as closely as possible to those of actual rolls in operation. The experimental results are shown, and are compared with previous data. The effect of stress concentration in rolls made of various materials is also considered.
An Analysis of Crushing and Pulverizing Processes
Authors: Work Lincoln T.
Published: April 2023

Different types of crushing and pulverizing mills are mentioned to show the diversity in operating characteristics. It is clear that different types of mills have been commercially adapted to similar products, and only rarely is one type of mill used to the exclusion of all others. The principles laid down illustrate the importance of grindability. A consideration of energy requirements shows that there is a large wastage of power over that needed to produce reduction in size. The earlier work of the author is confirmed on the difference in fineness-distribution curves produced under different grinding conditions and by different types of mills. Proper choice of mill, proper loading, and the application of separators offer the opportunity to produce material of specific size characteristics or to produce material below a given size at a minimum of cost.
High-Pressure Steam-Generator Research: Progress Report of Investigations at Purdue University by the A.S.M.E. Special Research Committee on Critical-Pressure Steam Boilers
Authors: Solberg H. L. , Hawkins G. A. , Willis P. A.
Published: April 2023

This is a progress report of the investigations with the high-pressure steam generator at Purdue University which have been carried on since January 1, 1932, and are mainly concerned with the measurement of the enthalpy of steam by the use of a condensing calorimeter designed for pressures up to 3500 lb per sq in. The heat leak was determined by assuming that the Keenan Tables were correct within the range at which the calorimeter was calibrated. Thirty-nine tests were carried on at pressures varying from 1900 to 3500 lb per sq in. and temperatures of 709 to 780 F. The results were compared with those of Keenan, Knoblauch, Callendar, and the International Tables. The Purdue University figures are in close agreement with those of Keenan, Knoblauch, and the International Tables, but show considerable variance from Callendar’s results.
Moisture Content, Specific Gravity, and Air Space in Wood
Authors: Maclean J. D.
Published: April 2023

An exposition of the physics of wood is given in the paper. It describes the cell structure of wood and the physical changes that take place as it is dried to oven-dry condition or impregnated to maximum absorption. Formulas and graphs give the relation that exists between percentage of moisture content, specific gravity, water content, total weight, and percentage of air space. The data are of interest to those engaged in wood research or wood physics or in kiln drying, wood preserving, or fireproofing.
Accelerated Varnish Drying
Authors: McCarthy R. H. , Lefcort L. A.
Published: April 2023

Varnish drying on wood at a temperature of 150 F, instead of the usual lower limit of 100 to 110 F, has been attained after experimentation and tests by the authors. This finish process retains the desirable factors of appearance, durability, economy, and speed. Varnish finishes at elevated temperatures are shown by tests to be superior to ordinary finishes in durability and resistance to marring. Samples made by this system have undergone accelerated weathering for several months without failure, indicating that those finishes that take advantage of the toughness and hardness resulting from the heat treatment of synthetic and some natural resins are superior to the ordinary run of long-oil varnish finishes. A feature of the system is that it makes feasible the conveyorization of varnish finishes as well as lacquer finishes.
Some Economic Aspects of the Rigid Airship
Authors: Fritsche Carl B.
Published: April 2023

In this paper the author tells of the uses to which rigid airships may be put, the cost of constructing, operating, and maintaining, and the probable return on investment that can be expected. Two hypothetical airships are chosen for comparison, one of 100 tons gross lift and the other of 300 tons lift. These are compared with ocean craft and with naval vessels. In naval application it is shown that one airship will release three cruisers for other duty, that the cruisers consume more power, and are more vulnerable than the airship.

Military applications of the airship include army transport, reconnaissance, coast patrol, and many other important uses. Theoretical conditions are assumed and many problems are worked out with use of airships. Civil and commercial applications of the airship are discussed, and a comparison is made with the steamship Leviathan. Operating schedules are laid out for airships in service between New York, Philadelphia, Washington, Havana, and Panama, and performance data are given. Commercially the airship is shown supplementing present facilities, transporting passengers, mail, and express at high speed, doing more work per unit of energy, saving much time, and earning considerable profits.
Airplane Tires and Wheels
Authors: Schippel H. F.
Published: April 2023

This paper tells of some of the mounting conditions of airplane tires on wheels, and of the relation between static load, ultimate cushioned load, and energy capacity. Static and dynamic loading curves and corresponding hysteresis loops are also presented, and the forces and power losses are resolved horizontally and vertically. Results of extensive wind-tunnel tests show the effects of tire size, wheel size, safety-tread design, streamlining, and tire misalignment.
Aviation Natural Gasoline
Authors: Alden R. C.
Published: April 2023

The usual natural gasoline of commerce is an extremely volatile product and quite unsuitable for direct use as a motor fuel in the conventional fuel systems of today. By careful fractionation, however, it has been found possible to produce “aviation natural gasoline,” a fuel that has made a splendid record commercially during the last three years. A considerable amount of research work has been done with regard to this product, and the author discusses it under the following heads: (1) Initial flight tests to determine specification bases for commercial purposes; (2) effects of changes in specifications for aviation natural gasoline; (3) survey of commercial aviation gasolines; (4) flight tests to determine actual temperature in airplane fuel systems; and (5) other investigations. An extensive table of test results of commercial aviation gasolines is included, as well as a bibliography of articles having a bearing on aviation natural gasoline.
The Layout and Design of Modern Airplane Plants
Authors: Plaisted G. W.
Published: April 2023

Plants for the manufacture of airplanes are in their design subject to the same general principles as are applied to all factory buildings. They must meet the requirements of straight-line production, flexibility, ample daylight, analysis of material handling, and the special needs of individual departments. Changes in methods of manufacture or changes in conditions should not affect a building so laid out originally as to permit of a flexible straight-line production process nor affect the maximum return on the investment. The author exhibits the general plant layouts and flow diagrams of four existing airplane plants and a typical cross-section of an economical factory building that might be converted to airplane manufacturing.
Stability and Controllability in Free Flight
Authors: Hovgard Paul E.
Published: April 2023

Making the airplane pleasant to fly is discussed by the author in this paper. Strength, durability, and performance of airplanes are determined quite accurately by analyses and tests, but the ease with which a particular plane can be maneuvered is often left to chance. Stability at cruising speeds and balance with the throttle closed and open are essential for ease of control. The author tells of various methods that can be used to test flying characteristics and make certain that airplanes will perform as desired.
Opportunities for Aviation Training
Authors: Marriott Joseph S.
Published: April 2023

In this paper the author endeavors to set forth the possible methods of obtaining adequate instruction and training to enter the aviation industry either as a pilot or in a ground capacity. The article is written from the practical viewpoint of training facilities available in the industry itself rather than opportunities presented by strictly educational institutions such as secondary schools and universities. The author also points out some of the advantages and disadvantages that are apparent in the existing means of obtaining aviation training.
Management and Operation of a Large Airport
Authors: Waterman Waldo D.
Published: April 2023

The policies and methods outlined indicate how an airport may be managed so as to take care of all interests. The author covers relations of the airport management with transport companies operating large fleets, with air-service operators having fleets of taxi and charter planes, with schools, with dealers and distributors, with manufacturers, with private owners of airplanes, with individual owners of single airplanes or small fleets for business purposes, and with the general public. Figures are given showing how a successful business has been built.
Plastic Torsion: An Experimental Determination of the Stress Distribution in a Bar Which Has Been Twisted to the Limit of Plasticity
Authors: Nadai A.
Published: April 2023

Among the locally varying distributions of stress with partial yielding, that of a twisted bar is treated, for which the transition from a state of equilibrium with purely elastic deformations to one with plastic deformations was investigated. An analogy described on an earlier occasion was utilized to determine by an experimental method the distribution of stress in the twisted bar. This distribution of stress was compared with the position of the thin layers of slip observed in the etched cross-sections of twisted steel bars.
Determination of Stresses in Rotating Disks of Conical Profile
Authors: Rushing F. C.
Published: April 2023

In this paper a determination is made of the accuracy of stress-distribution curves obtained by the application of Donath’s “Sum and Difference Curves” to rotating disks of conical profiles.
The Collapsing Strength of Steel Tubes
Authors: Jasper T. McLean , Sullivan John W. W.
Published: April 2023

In this paper the authors present a method for determining the collapsing strength of steel tubes on the basis of the physical and elastic properties of the metal in the tube, and the dimensions, out-of-roundness, and variation in thickness of the tube. This method applies to long, short, thick, or thin tubes. It was developed by considering the collapse of tubes in terms of compressive stress rather than external pressure, by reevaluating the work of other investigators, and from experimental results of the authors. Its application to the determination of the collapsing strength of commercial tubes is shown by illustrative examples.
Soot Particles in New York City Air
Authors: Free E. E.
Published: April 2023

In this paper the author tells of the methods used and the results obtained in a series of counts of soot and dust particles in the air of New York City. The counts were made by an impact dust counter. Two variables affect the results. One is the wind and the second the degree of clumping or flocculation of the soot particles in the air. The number of soot particles counted showed a high degree of correlation with wind direction. Nothing was discovered to show the causes for clumping of the soot particles.
Recovery of Fly Ash From Pulverized-Fuel Stacks by Use of Stack Sprays
Authors: Mackenzie J. W.
Published: April 2023

One of the first central stations designed for the unit system of pulverized-fuel operation with preheated air encountered difficulty due to fly ash from the stack. The extent of the trouble was determined by locating boards freshly painted with white paint throughout the district. A water spray installed in the stack stopped all complaints, but necessitated lining the stack with acid-resisting material. Tests show that with the spray in operation about 5 per cent of the coal is discharged as solids from the stack, and that the spray takes out about 35 per cent of the solids coming to the stack. A detailed description is included of the equipment and methods used for collecting representative samples of the solids in the flue gases.

This paper outlines the influences which led the Consumers Power Company to adopt a spray system in the stacks of its pulverized-fuel fire plants as a means of combating the fly-ash problem, and shows the results which operation and tests have revealed as to the effectiveness of the system.
Experiences in Chlorinating Condenser Circulating Water
Authors: Frost Vincent M. , Rippe W. F.
Published: April 2023

This paper gives the experiences of the authors over a period of two years in an endeavor to better the heat transfer and reduce condenser cleaning costs at the Kearny, N. J., power station of the Public Service Electric & Gas Company. The condensing apparatus there consists of five 50,000-sq. ft. condensers of the two-pass type, each having 10,000 one-inch tubes 19 ft. 2½ in. long. Chlorine control apparatus was installed, and the paper gives details regarding its operations, and includes water analyses, as well as data on condenser tests, amount of chlorine required, etc. The advantages and disadvantages of chlorination are set forth, together with the reasons for adopting it for the station in question.
High-Burned Kaolin Refractories
Authors: Norton F. H.
Published: April 2023

The development of high-fired kaolin refractories is briefly described. The various products made from kaolin such as brick, tank blocks, light-weight brick, and insulators, are discussed from the point of view of their physical characteristics. Also, the service results obtained with these products in typical installations for the past ten years are outlined. The results as a whole show that kaolin, when burned to a sufficiently high temperature, will make a refractory possessing very desirable qualities.
Heat Absorption in Water-Cooled Furnaces
Authors: DeBaufre Wm. L.
Published: April 2023

Based on the furnace heat balance, an empirical “effectiveness factor” is derived for water-cooled surfaces therein, relating the heat radiated by the burning fuel and products of combustion to the furnace-outlet temperature. The value of this factor is calculated from certain experimental data for turbulent horizontally fired pulverized-coal furnaces with bare water-cooled tube walls. For these experimental data, the fraction radiated of the heat liberated in the furnace has also been calculated and is compared with Broido’s curve and with the value calculated by the Orrok-Hudson formula. The method of applying the effectiveness factor to design problems is illustrated by showing the effect of preheated-air temperature upon the furnace-outlet temperature.
Furnace-Gas Compositions and Temperatures in Underfeed-Stoker-Fired Boilers, and Their Effect on Boiler Settings
Authors: Pasini Albert C. , Sarraf Edward M.
Published: April 2023

This paper is a study of conditions encountered in boiler furnaces using underfeed stokers. It includes the development of methods of test procedure and their application in investigating furnace-gas compositions, and of determining the temperatures to which the refractories of the setting are subjected. It contains a discussion of the effects of variation of the fuel-bed thickness on the brick in the settings, the efficiency of combustion, and the resultant superheated-steam temperatures. The paper further shows the widely divergent furnace-gas compositions which may be obtained directly over the fire along the wall in underfeed-stoker-fired installations.
Combined Burners for Firing Waste Fuels
Authors: Vroom R. C.
Published: April 2023

Waste by-products of oil refining, formerly difficult of disposal, are now burned in special plants to furnish electric and steam power. This is made possible by the design of high-capacity burners, some liberating 100,000,000 B.t.u. per hour. The author describes a wide-range mechanical atomizer of the circulating type and the results of an installation at the Louisiana Station at Baton Rouge of the Louisiana Steam Products, Inc. The burners are successfully firing crude or lubricating (acid) sludge, soda bottoms, neutralized sludge, acid tar, wax tailings, and flux bottoms, in addition to fuel oil.
Calibration of a Large Nozzle
Authors: DuPriest John R. , Polhemus James H.
Published: April 2023

In testing large centrifugal pumps it is difficult to determine the amount of water that is being handled. In many cases the quantity is so great it is almost impossible to determine it by the ordinary field weighing system. The use of standard test nozzles offers a simple means of determining the capacity of large pumps, but the nozzles must be accurately calibrated. The authors made a test of three pumps by laying about 1000 ft. of pipe behind a dredge and attached standard nozzles to the end of the pipe line for calibration purposes. The quantity of water flowing was determined by the salt-solution method.
Application of Hydraulic Laboratory Researches
Authors: Winter Ireal A.
Published: April 2023

This paper presents results of laboratory investigations made in connection with hydroelectric power-plant designs, the problems encountered leading up to the establishing of a policy of conducting research, the method of testing, and comparisons of laboratory and field results. The object is to illustrate the many advantages of model investigations and to point out the deficiency of scientific knowledge incidental to power-plant design, with the hope that interest will be stimulated in pure-science research. Hydraulic research may be classified under two subdivisions: complex flows created by natural active and reactive forces, such as river channels, harbors, estuaries, tidal effects, etc., and, second, manufactured structures, such as spillways, canals, penstocks, hydraulic machines, etc., where the active and reactive forces should be definitely predicted by the designer. This paper deals with the latter, principally in connection with hydraulic turbines and their associated parts. Results will be shown where slight changes in shapes raise or lower the efficiency of hydraulic machinery as great as 1 per cent. No attempt is made to specifically account for the results obtained, but the apparent inconsistency of performance of water passages designed according to the limited knowledge of positive and negative acceleration will be evident to hydraulic engineers engaged in the utility field.
Apprentice Training Movement in Wisconsin Industry
Authors: Falk Harold S.
Published: April 2023

The apprenticeship movement in Wisconsin has been made a concerted organized effort. In developing the work important considerations and tendencies have been taken into account, such as the shortage of skilled mechanics in American industries at the present time in spite of considerable unemployment, the requirements of production as well as of jobbing industries for trained men, and the importance of the human factor in all industry. Employers and employees have cooperated in the promotion and support of an apprenticeship law in the state which stabilizes and dignifies apprenticeship by preventing exploitation of boys and by setting standards of workmanship in the trades. As a result of public favor and the enthusiasm of influential individuals, apprentice training has developed rapidly in the state. There are 3350 apprentices employed and 2567 have graduated in the last 15 years. At the present rate of graduation, this number will be increased very much in the next 15 years.

However, neither the Industrial Commission nor the industrial leaders are satisfied with the progress which has been made. The number of apprentices in the state is inadequate compared with actual requirements for skilled men in the trade. Nevertheless, an excellent foundation has been laid upon which greatly increased activity may be built in future years.
Management by Exception
Authors: Lord Chester B.
Published: April 2023

The exception principle, as approved by the first leaders of industrial management, is expounded and advocated. It is described as a natural method of scientific management that directs when direction is sufficient and that compels when compulsion is called for, but that does not interfere with matters which are progressing in orderly compliance with a planned procedure, but which has positive methods of detecting and correcting variations from that procedure. Four rules of management by exception are stated.
Value of the Safety Movement in the Industries
Authors: Podnossoff Jules
Published: April 2023

The paper outlines the various aspects of the industrial safety movement, its attractiveness, economies, and inherent possibilities. The safety movement has been long ago divorced from altruistic conversation and put on a basis of cooperative helpfulness. Accordingly, the subject has been treated from a “cold” business standpoint in terms of dollars and cents; that is, in the approach to the problem the center of gravity has been shifted to the economic rather than humanitarian aspects. A brief historical review of the growth of the movement is first made, followed by some statistics of the losses in life and property caused by industrial accidents. The principal emphasis in what follows has been placed on the thesis, at present conclusively proved, that efficiency in production and safety are inseparably correlated. To afford a better perspective of the actual values involved, illustrative examples taken from the experience of different industrial companies are introduced. The role of engineers in accident prevention is next considered, and the discussion is concluded with several recommendations.
Symposium on the Stability of Employment in Industry: Employment Stabilization in the Procter & Gamble Company
Authors: Knowles Harvey C.
Published: April 2023

The history of one company in stabilizing employment is detailed. Having but three presidents over a period of 93 years, a definite family policy has been carried out, resulting in a plan that virtually guarantees an employee that he shall have work for 48 weeks during the year; that he shall have a share in the profits; that in case of sickness he shall receive two-thirds of his pay for a year and a pension in case of disability; that he may participate in a home-buying plan.
Case-Hardening With Ammonia Gas
Authors: Homerberg V. O. , Walsted J. P.
Published: April 2023

It has been the dream of metallurgists for many years to produce a steel of good toughness with maximum surface hardness and wear resistance. To produce these properties with a minimum of distortion has been the subject of much research work of a high order. In the past the most successful method of obtaining these properties has been by subjecting low-carbon steel to the action of a carburizing material at high temperatures. Under these conditions the steel takes up carbon in its surface layer, changing that portion of the material into a high-carbon steel capable of hardening, while the core remains low in carbon with the usual toughness and shock-resisting properties. By a suitable double heat-treatment the core can be brought to maximum physical properties while the case can be made hard and wear-resistant. This process of case-hardening by means of carbon is somewhat cumbersome. The necessary heat-treatment after carburizing is a frequent cause of distortion of the hardened parts.

A new process of case-hardening has been developed which has all the advantages of the older method. Besides being free from the troublesome warpage it surpasses the older method in the hardness of the case produced. The classic research of Doctor Fry at the Krupp Works, Essen, Germany, is responsible for the introduction of this valuable metallurgical development. Researches of a very high order in France and in this country have brought the process to its present high state of development. A great deal of credit is due Dr. Norton and Mr. De Fries of the Ludlum Steel Company for the excellent work which they did immediately after the introduction of this process into this country several years ago. This new process, known as “nitriding,” now a commercial success, is described by the authors in this paper.
Replacing Metals by Synthetic Resins—Phenol-Resinoid Molding Technique
Authors: Quigley Leon V.
Published: April 2023

It is the purpose of this review to assist the engineer and mechanic whose experience has been chiefly with metals to get his bearings with regard to the synthetic resin plastics, which are becoming increasingly important in the metal trades. The paper deals particularly with that type of plastic or synthetic resin materials known as phenol resinoids. The review has involved a study of the literature of America, England, and the Continent covering the past five years, and relies also upon the technical archives of the American company which, during the past 20 years, since the inception of these materials, has been engaged in their manufacture.
Fundamentals of Machine Polishing
Authors: Kent Robert T.
Published: April 2023

The success of machine polishing depends on the proper coordination of the variables present in the work itself, in the polishing wheel, in the abrasive, in the machine, and in the glue used in setting up the polishing wheel. These variables are discussed in detail, and their relation to each other are set forth. Typical polishing machines are described, as well as examples of successful machine polishing.
Tool-Steel Tools
Authors: d’Arcambal A. H.
Published: April 2023

Metal-cutting tools offered the trade today are vastly superior in quality to tools of a decade ago. The factors that govern the life of metal-cutting tools made from carbon, alloy, and high-speed tool steels, namely, design, steel, and treatment, are discussed in this paper, particular stress being laid on the importance of correct design.

The important role played by cutting fluids or coolants as affecting the life of the tool, as well as the necessity of employing the proper grinding wheels and correctly using them, are also covered in some detail.