bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Direct Firing of Pulverized Anthracite Silt
Authors: Frisch Martin 
Published: February 2023

Abstract
The purpose of this paper is to describe a recent development in the art of burning pulverized fuels. It is now commercially practicable for the first time to substitute for the bin-and-feeder, or storage, system a simpler and less costly direct-firing, or unit, system for burning pulverized anthracite culms and silts heretofore considered unsuitable and unmarketable as fuels.
Boundary-Layer Flow Over Flat and Concave Surfaces
Authors: Blaisdell Allen H. 
Published: February 2023

Abstract
Boundary-layer characteristics are of interest not only because of their effect on airplane wing drag and lift, but also because of their intimate relation to the “interference drag” which so far has received relatively little attention from the standpoint of boundary flow. For this reason the author encouraged Charles B. Lyman, a postgraduate student at the Carnegie Institute of Technology, to initiate experimental work which might lead to this objective. Accordingly, the contents of this paper are based on the results of this thesis investigation which was carried out under the general supervision of the author during the college year 1934–1935. Due to lack of space and time many of the test data cannot be presented, but an attempt will be made to cover the more important and interesting results of the investigation.
Failure of Metals Due to Cavitation Under Experimental Conditions
Authors: Boetcher H. N. 
Published: February 2023

Abstract
The author is discussing cavitation experiments conducted at the Holtwood laboratory of the Safe Harbor Water Power Corporation and shows that metallurgical examination supports the results of hydraulic research in so far as the mechanical character of cavitation is concerned. This support is given by indicative Rockwell hardness tests which show, with many metals, appreciable hardening of the surface affected by cavitation, by strain lines in copper alloys and austenitic steels, and by the type of failure. The author points out that the small area affected by the individual blows and the characteristics of the blows result in particular conditions which would justify the use of a special term for this type of attack, such as “cavitation fatigue.” He concludes that in order to have high resistance against cavitation fatigue, the metal should have high corrosive resistance in the water in which it is used, and physical and metallurgical properties which result in high fatigue resistance.
Plunger Lift for Pumping Deep Wells
Authors: Fletcher H. W. 
Published: February 2023

Abstract
Conditions in the operation of deep wells are unfavorable in general to the economical performance of displacement pumps. The plunger-lift method of raising oil from deep wells avoids high operating pressures and close-fitting moving parts, and therefore reduces maintenance, the chief expense item in the handling of pumping properties. This equipment, operating on relatively low gas pressures, is well adapted to supplement gas-lift installations and in general utilize the initial investment in such auxiliary equipment as compressors, separators, and piping to produce the property down to the point of abandonment. The plunger lift is so designed that high working stresses are eliminated, thus avoiding rapid deterioration and resulting in nearly 100 per cent salvage value. Field tests indicate that a material reduction in lifting costs can be obtained by the use of this pumping method.
Development of the Air-Float Method of Gravity Separation
Authors: Slaymaker R. R. 
Published: February 2023

Abstract
The author gives the historical background and reviews the development of the air-float or pneumatic type of gravity separator used by the producers of such commodities as seed, beans, peas, peanuts, rice, wheat, coffee, cork, and coal. The principle of this type of separator is based on the fact that when particles of approximately the same size but of varying densities are fed over a porous table through which air is being blown at a velocity such that the lightest particles are held at the point of suspension, there is a tendency to stratify the mass with the heaviest particles nearest the table and the lightest particles farthest above the table. When in addition, the table is given a motion similar to that of a grasshopper conveyor, the heavy stock will climb the conveyor faster than the light stock, thus grading the particles from light to heavy all along the table.
The first machine described by the author is an electrostatic separator which was designed to concentrate dry placer consisting chiefly of silica, iron oxide, and free gold. This first design was discarded because of low capacity, and a pneumatic jig was designed with an inclined conveyor belt of porous material across which wooden cleats were fastened. A chance inspection of the Wilfley table, a wet-process concentrator, led inventors Sutton, Steele and Steele to use a flat reciprocating conveyor instead of the belt conveyor in their pneumatic jig. A demand for increased capacity of the latter design, which has constantly been improved, has led to the steadily enlarging field for the application of the air-float gravity separator.
Arc Welding of Structural Alloy Steels
Authors: Warner W. L. 
Published: February 2023

Abstract
The author discusses the effect of welding heat on different structural alloy steels. This heat effect, expressed in terms of Vickers Brinell hardness, is affected by the physical and chemical properties of both the parent metal and the electrode used. The author presents graphs showing the extent of the effect of these properties on the welded structure and on the weldability of the material.
The Welding of Aluminum Alloys
Authors: Hoglund G. O. 
Published: February 2023

Abstract
The author discusses the use of gas, metallic-arc, and electric-resistance welding of aluminum but points out that although other forms of welding are applicable to the fabrication of aluminum products, none as yet are of commercial significance. The author includes references to the types and gages of aluminum alloys suitable for welding, the difficulties encountered in welding the alloys, the types of equipment used in the welding processes, and methods in use for the fabrication of aluminum products. He also mentions some of the industrial applications where welded-aluminum products can be used profitably.
Hydraulic-Laboratory Projects of the Corps of Engineers, U. S. Army
Authors: Falkner F. H. 
Published: February 2023

Abstract
Probably no other single engineering unit has had the privilege in recent years of undertaking a program of experimental hydraulics as broad in scope and as extensive in application as that carried on by the Engineer Department of the U. S. Army. The breadth of the program, involving 303 separate experiments conducted by 41 division and district offices scattered over the entire country, makes it impossible to deal with specific cases in this paper.
Hence, the purpose of this paper will be to present, in broad general outlines, the hydraulic-laboratory work of the Corps of Engineers. Specifically, it will touch upon the types of field problems subjected to experimental analysis, the facilities maintained for this work, and the accomplishments of the program. No effort will be made to explain the laboratory methods employed, since they conform generally with the methods and technique described by L. J. Hooper. It is hoped that this paper will serve the engineering profession as an index of the facilities and sources of experimental data available in the Engineer Department of the U. S. Army.
History and Present Status of Research and Specifications of Diesel Fuel Oil
Authors: Becker A. E. , Reed M. J. 
Published: February 2023

Abstract
The authors refer to the need for specifications and a classification of Diesel fuel oils, and discuss what has been accomplished in this respect by the various organizations interested in the subject. The following properties of fuel oils are discussed to clarify the meaning of each in the specifications of fuel oils: Ignition quality, viscosity and pour point, carbon residue and ash, water and sediment, sulphur, and flash point. A review of objectives of fuel-oil research concludes the paper.
Square-Edged Inlet and Discharge Orifices for Measuring Air Volumes in the Testing of Fans and Blowers
Authors: Marks Lionel S. 
Published: February 2023

Abstract
This is the third paper presented by the author to the A.S.M.E. on the flow of air in fan ducts. In the first paper, it was established that the normal flow in such ducts is vortical in character and that the use of straighteners is necessary in order to obtain a reliable air-volume measurement. The second paper contained proposals for (1) the adoption of a specified design of pitot tube as a standard in fan testing and (2) the use of square-edged inlet or discharge orifices for measuring air volumes except at or near maximum fan capacities. In the present paper, the results of an extended series of investigations on a simplified form of square-edged orifice are presented. The discharge coefficients obtained in these investigations are identical with those found in extensive German tests and adopted in the standard rules of the V.D.I. and by the International Standards Association. This agreement justifies the use of the coefficients for the large-sized ducts and the varieties of velocity distribution found in fan discharge ducts. The substitution of inlet and discharge orifice measurements for pitot-tube traverses and the adoption of these coefficients in a fan-testing code would, the author believes, greatly shorten and simplify the process of testing a fan and would make it more accurate.
Undercooling in Steam Nozzles
Authors: Rettaliata J. T. 
Published: February 2023

Abstract
This paper deals primarily with the effect of wall roughness on the flow of steam in nozzles; and secondarily with drop growth and the occurrence of initial condensation. It was found that roughness of the nozzle walls caused a retardation of steam flow and resulted in the Wilson line’s occurring at the 3.2 per cent moisture line on the Mollier diagram instead of at the 3.7 per cent moisture line as was found for a nozzle with smooth walls. In a specially designed nozzle drop growth was accomplished as evidenced by the complete visible spectrum which resulted from the scattering of light by the expanding steam in this nozzle. Photographs of the condensation region show that condensation is not occurring at any point previous to where the eye sees it. These researches indicate that the location of the Wilson line on the Mollier diagram depends entirely upon the rate of change of velocity of the steam, and, therefore, cannot be fixed for all conditions. In accordance with this fact it is suggested that the term “Wilson line” is a misnomer and should be replaced by the more appropriate one of “Wilson zone.”
Turbine Supervisory Instruments and Records
Authors: Roberts J. L. , Greentree C. D. 
Published: February 2023

Abstract
This paper includes a description of a set of instruments for the electrical measurement and detection of such mechanical quantities as shaft eccentricity, bearing vibration, shell expansion, and interference or rubbing of rotating parts. It also contains an analysis of typical, as well as special, starting- and loading-sequence records taken on a 160,000-kw steam and a 20,000-kw mercury-vapor turbine generator, and conclusions which pertain to the adaptability of the instruments to turbine operation.
A Study of Cutting Fluids Applied to the Turning of Monel Metal
Authors: Boston O. W. , Gilbert W. W. 
Published: February 2023

Abstract
This paper presents the results of an experimental study of the application of cutting fluids to the turning of monel metal. The manner in which high-speed-steel tools wear and fail is discussed. By competitive tests the tool life of the large-radius tool is compared with that of a straight-edged small-radius tool. The practical advantages of each are discussed. Cutting-speed tool-life curves are obtained and equations developed for the latter tool when turning monel metal with deep thin cuts and shallow thick cuts for each of several types of cutting fluids. The influence of feed and depth of cut on tool life at various cutting speeds is determined when turning monel metal with a sulphurized mineral oil. Finally the three components of the cutting force are determined for various combinations of feed and depth of cut when turning monel metal with an emulsion.
Comparative Torque and Horsepower Requirements of Standard Four-Flute and Spiral-Flute Taps
Authors: Daasch Harry L. 
Published: February 2023

Abstract
This paper reports certain tapping tests performed as a part of a research project of the Iowa Engineering Experiment Station at Iowa State College.
Data are presented on the torque and horsepower requirements for the use of ½-in., 13-thread, standard-flute, and spiral-tip flute taps during the tapping of S.A.E. 1020 steel. The torque values are shown to vary with speed when a constant percentage of thread is produced. The torque increased with speed when lard oil was used as a cutting fluid; the tendency was toward decreased torque with increased speed when sulphurized oil was used. Spiral-tip taps required less torque than straight-flute taps at similar cutting conditions. Horsepower requirements were found to be less with sulphurized oil than with lard oil at high percentages of thread depths for both kinds of taps. Spiral-tip taps could be operated at lower horsepower inputs than could the straight-flute style when similar cutting conditions exist.
Another series of tests pertains to the dry tapping of cast iron with ⅜-in., 16-thread taps. There was little difference in the torque requirements when the two types of taps were used. Slightly lower horsepower input is shown for the spiral-tip tap.
Coal Preparation by the Air-Sand Process
Authors: Fraser Thomas 
Published: February 2023

Abstract
The author presents in this paper the features of an air-sand process for the preparation of coal by specific-gravity separation. In this process, the float-and-sink separation is made in an artificial dry liquid medium of sand and air which can be adjusted within certain limits to the specific gravity needed to give a satisfactory coal product. This dry float medium of sand and air is produced by passing a continuous flow of air bubbles upward through a bed of dry sand in a separator box. The author discusses the construction, operation, and effectiveness of the equipment used in the process.
The Use of Alloy Steels for Side Frames and Bolsters of Freight-Car Trucks
Authors: Barrows Donald S. 
Published: February 2023

Abstract
The author reviews briefly the use of different types of side frames for railway freight-car trucks, including arch-bar side frames, cast-steel side frames with separate journal boxes, and side frames with the journal boxes cast integral with the truss members. He discusses the present-day trend toward the use of high-tensile-strength cast alloy steel for truck side frames and bolsters, and gives results of static and dynamic tests made on truck members cast from alloy steel and A.A.R. grade-B steel.
The Interpretation of Creep Tests for Machine Design
Authors: Soderberg C. Richard 
Published: February 2023

Abstract
The author presents a method of interpreting creep-test data and applies the method to several problems of machine design. The method involves a rational theory of plastic flow in polycrystalline materials to which empirical results from actual tests can be applied. The basic premise of the theory proposed is that the facts already established for plastic flow at “normal temperature” remain valid for higher temperatures as well.
The Creep Curve and Stability of Steels at Constant Stress and Temperature
Authors: Weaver S. H. 
Published: February 2023

Abstract
The creep rate for steels at constant stress and elevated temperature is composed of (1) the strain hardening with a rate which varies inversely with time, and (2) an asymptotic constant creep rate. The sum gives the creep rate at any time, and the formula for the total creep-extension curve.
For steels with a physical or structural change during creep, a third quantity must be added to the creep-extension formula, the test value of the quantity indicating the degree of instability of the test metal.
To illustrate four of the principal types of instability, the author presents four sets of long-time creep tests extending from 5500 hr to 5 yr. They represent changes due to (1) carbide spheroidization, (2) ferritic banding, (3) dendrites, and (4) alloy segregations.
Design and Operating Problems With Gas- and Oil-Fired Boilers for Stand-By Steam-Electric Stations
Authors: Estcourt V. F. 
Published: February 2023

Abstract
The problem of stand-by operation, although not new on the Pacific coast, is a comparatively new experience for large units operating at pressures above 400 lb and temperatures above 700 F. With combination gas and fuel-oil installations, there are more difficulties to overcome with fuel oil than with gas. The paper describes problems in the control of flame angle when burning fuel oil and developments in high-speed automatic combustion control which make possible the acceptance of emergency loads from 5 to 90 per cent of turbogenerator capacity as fast as the turbine governors can open the control valves. Various operating procedures which have been developed as a necessary routine to meet stand-by conditions are also described. The essential requirements for stand-by and base-load operation are compared. Descriptions are given of actual load-pickup tests on a 1400-lb, 750-F reheat plant and a 425-lb, 750-F plant, and the actual events which take place in the first few seconds of an emergency load pickup are analyzed from the standpoint of what should be provided for in the design of boiler storage capacity, and speed of combustion control. Statistics relating to these features are given for four plants on the Pacific Coast.
Rotary Drilling Rigs Operated by Internal-Combustion Engines
Authors: MacCargar D. M. , Haas O. A. 
Published: February 2023

Abstract
The authors discuss the use of internal-combustion engines as prime movers for rotary drilling rigs. They show diagrammatically the advances made in the application of internal-combustion engines to rotary drilling, and the different methods of connecting the engines through mechanical and electrical means to the drilling equipment.
Determination of the Effect of Certain Installation Conditions on the Coefficients of Sharp-Edged Orifices
Authors: Beitler S. R. , Overbeck J. E. 
Published: February 2023

Abstract
This paper presents the results of a study made to determine the effects of certain installations on the coefficients of discharge of sharp-edged orifices. The coefficient determinations were made with the orifice plates clamped between flanges made up on the end of pipe so that no appreciable gap existed between the end of the pipe and the orifice plate. Some of the orifice flanges were constructed with a core or recess which left a gap of an inch or more between the end of the pipe and the orifice plate, this being done to simulate meters of this type now used to a greater or less extent. The authors present results obtained from the tests of such orifices set in 2-, 4-, and 8-in. pipes, as well as results from tests of standard-reference orifices. All results are presented graphically.
Analysis and Tests on Hydraulic Circuits of Surface Condensers
Authors: Van Hengel G. H. 
Published: February 2023

Abstract
Illustrated by actual test results, this paper deals with an analysis of hydraulic circuits of surface condensers. The losses in the tubes, condenser water boxes, and piping are treated in detail. The importance of the weir losses in the outlet box is demonstrated. Tests on condensers with and without a weir show the actual gain in hydraulic efficiency obtained without a weir. An exact method is given for the calculation of the liberated air in determining the hydraulic-circuit losses. Since the amount of air liberated governs the rate of corrosion of the tubes, this calculation is of considerable importance, especially for salt-water conditions.
Oil-Film Thickness at Transition From Semifluid to Viscous Lubrication
Authors: Karelitz G. B. , Kenyon J. N. 
Published: February 2023

Abstract
This paper describes tests in which flat-faced pieces of several bearing metals were mounted to ride on a small journal which was lubricated by means of an oil bath. The initial lines of contact gradually developed into grooves until viscous oil films formed between the rubbing surfaces and arrested further wear. The minimum thickness of these wedge-shaped oil films were computed from observations made with tin-base, lead-base, bearing-bronze, and leaded-copper bearing metals, each being tested under loads of 20, 40, and 60 lb per sq in., respectively. It is shown that the film thickness is substantially independent of the load for any one individual material, ranging from 0.00003 in. to 0.00006 in. Photomicrographs of the surface structures of the bronze and tin-base babbitt are shown, which permit measurement of the height of excrescences. These measurements compare favorably with the computed values of minimum oil-film thickness. The observations are correlated with those given by McKee (6) obtained on the running in of small bearings. The effect of different oils on the running in of babbitt is also indicated.
Pitting Resistance of Metals Under Cavitation Conditions
Authors: Mousson J. M. 
Published: February 2023

Abstract
The paper describes the experimental apparatus and testing procedures used to determine the pitting resistance of metallic materials under accelerated cavitation conditions. The results of this research, sponsored by the Safe Harbor Water Power Corporation, are compiled in a series of tables and the classification of metals is discussed in the light of the metallurgical data made available for the materials and the metallographic analysis carried out in connection with the research program. The conclusion is reached that a more rational approach has been provided for selecting materials subject to attack by cavitation.
Long-Time Creep Tests of 18 Cr 8 Ni Steel K19 and 0.35 C Steel K20
Authors: Cross Howard C. , Lowther J. G. 
Published: February 2023

Abstract
This paper, submitted under the sponsorship of the Joint A.S.T.M.-A.S.M.E. Research Committee on Effect of Temperature on the Properties of Metals, is a report on long-time creep tests now in progress on water-quenched 18 per cent Cr, 9.5 per cent Ni, 0.067 per cent C steel K19 at 1200 F and on an annealed 0.35 per cent C steel K20 at 850 F.
One test on the K19 steel loaded to 8345 lb per sq in. at 1200 F was discontinued at 11,467 hours and a second test has now progressed to 15,185 hours.
Of the K20-steel tests at 850 F, one test at 8000 lb per sq in. was discontinued at 10,955 hours, and a second test at 7500 lb per sq in. has now progressed to 12,214 hours.