bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanical Design in Oil-Shale Retorting Plants
Authors: Brakel L. H. 
Published: July 2022

Abstract
For retorting of oil shale, the primary elements are handling of large quantities of crushed shale, in a satisfactory manner for good heat exchange, through a suitable retorting vessel; generation of the necessary heat at the temperatures required for retorting; controlled exchange of heat to the shale in the amount required for retorting; passage of a carrier fluid through the retorting shale to pick up the retorted oil; and further passage of this carrier fluid with the retorted oil through suitable equipment to separate and recover the oil from the fluid stream. Of the processes tested experimentally by the Bureau of Mines at Rifle, Colo., the gas-combustion process is most efficient and most economical in operation. No water is required. The simplicity of the design, the gravity flow of shale through the retort, the heat-exchange zones to keep all practicable heat within the retort, and the few simple mechanical devices make this retort both low in construction cost and most economical in operation.
Low-Temperature Insulation for Refinery Service
Authors: Martin W. L. 
Published: July 2022

Abstract
The problem confronting the refinery engineer in the selection, application, and maintenance of an insulation for low-temperature service involves consideration of factors that are, in general, of only minor significance in the high-temperature field. The principal basic factor in any insulation is, of course, conductivity. However, water absorption, upper-temperature limit, fire resistance, coefficient of expansion, and so on, also must be considered in selecting an insulant for particular service conditions. This paper presents a discussion of the more common insulating materials and the relative importance of the various properties and characteristics of these materials for low-temperature service in petroleum refineries. In addition to the care exercised in obtaining the proper insulating material, considerable attention must be devoted to the selection of accessory materials such as adhesives, vapor sealers, water and fireproof coverings, mechanical securement devices, and the like. These materials also will be discussed since they have a pronounced effect on the over-all effectiveness and life of the insulation.
The Determination of Local Forced-Convection Coefficients for Spheres
Authors: Cary John R. 
Published: July 2022

Abstract
The local heat-transfer coefficient on the surface of a sphere is investigated in the range of Reynolds numbers from 44,000 to 151,000. Correlation of experimental data is based on the Nusselt and Reynolds numbers, and two curves are presented for the relation between the Nusselt and Reynolds numbers as a function of the angle from the stagnation point.
Pressure Operation of Large Pulverized-Coal-Fired Boilers on the American Gas and Electric System
Authors: Bice G. W. , Yeknik W. M. 
Published: July 2022

Abstract
In 1946 a detailed study was made of the possibility of applying a special pressure-tight steel casing to the boilers for two projected 150,000 kw capability units, for the purpose of permitting operation with forced draft only. Factors influencing the decision to proceed with this type of construction are reviewed in detail. Operating histories, as affected by the pressurized construction, are reviewed for these two units and for four subsequent additional units of similar design. The principal difficulties which were encountered are enumerated and measures which were taken to overcome these difficulties are discussed. Static-pressure operating levels, auxiliary power, and thermal efficiency comparisons are given for pressure operation versus suction operation.
The Influence of Higher Rake Angles on Performance in Milling
Authors: Crawford J. H. , Merchant M. Eugene 
Published: July 2022

Abstract
This paper presents the results of research on the influence of rake angle on metal-cutting performance when using high-speed-steel cutters. A range of rake angles and cutting speeds was selected and studies made on cutter life and surface finish as a function of these variables. The effect of these variables on such basic quantities as forces, shear angle, chip friction, work done in cutting, and the calculated temperature on the chip-tool interface also was investigated. In several cases, excellent performance was obtained using higher rake angles (of the order of 25 deg to 40 deg) at higher cutting speeds. This observed performance is analyzed in relation to the basic factors.
Grinding and Lapping Stresses in Manganese Oil-Hardening Tool Steel
Authors: Letner H. R. , Snyder H. J. 
Published: July 2022

Abstract
The biaxial stress distributions resulting from grinding and lapping annealed manganese oil-hardening tool steel were determined by sectioning the stressed surface layers and following the changes in curvature of the test specimens by optical interferometry. Two methods of sectioning, lapping, and chemical etching were tested and evaluated. Results of the study show that the plastic deformation which gives rise to the residual stress is at least partially due to mechanical forces exerted upon the surface by the abrasive grains and cannot be explained by forces of thermal origin alone. Grinding stresses were found to fluctuate rapidly close to the surface, the highest stresses being confined to a surface layer about 0.0001 in. thick. Depth of stress penetration increased with depth of cut over the range tested. Lapping stresses were found to have a nearly constant compressive value throughout the surface layer affected which, for the conditions investigated, was about 0.0002 in. thick.
Furnace Heat Absorption in a Spreader-Stoker-Fired Steam Generator: 1—Furnace Heat-Absorption Efficiency as Shown by Enthalpy of Gases Leaving the Furnace
Authors: Myers J. W. , Corey R. C. 
Published: July 2022

Abstract
This paper is part of the fifth of a series of reports on investigations of heat absorption and distribution of heat transfer in large steam-boiler furnaces, sponsored by the ASME Special Research Committee on Furnace Performance Factors. The furnace heat absorption was determined from the temperature and composition of the furnace exit gases in fifteen tests on a steam generator rated at 165,000 lb per hr of steam at 915 psig and 740 F at the superheater outlet, and which is fired by a spreader stoker on a front-discharge traveling grate. The effect on furnace heat-absorption efficiency is shown for variation of (a) the heat available in the furnace, (b) the excess air, (c) the percentage of combustion air admitted over the fuel bed, and (d) the condition of the furnace walls with respect to ash deposits. Detailed data on the distribution of gas temperature and of excess air in the furnace are presented. The experimental values for the furnace heat-absorption efficiency did not compare favorably with values calculated by either the Stefan-Boltzmann or the Wohlenberg equations. There is evidence, however, that the performance of a spreader-stoker-fired furnace might be predicted by the Wohlenberg equation if it were modified to allow for heat transfer resulting from a combination of suspension and fixed-bed burning.
Laboratory Investigation of Superheater-Tubing Materials in Contact With Synthetic Combustion Atmospheres at 1350 F
Authors: Slunder C. J. , Hall A. M. , Jackson J. H. 
Published: July 2022

Abstract
A group of commercially available alloys was tested for resistance to synthetic combustion atmospheres at 1350 F, in controlled laboratory experiments, to determine their suitability for use as superheater-tubing materials. Variables in the corrosive environment included two concentration levels of sulphur dioxide, carbon monoxide, and alkali-metal salts. Evaluation on the basis of resistance to both scaling and subsurface corrosion showed that alloys of the 25–12 and 25–20 types were superior. AISI 304 also behaved very well in these tests. These results verify the conclusions of the field tests in installations burning low-sulphur natural gas or coal. The conditions obtained in burning high-sulphur, high-vanadium oil were not included in the laboratory tests.
Resistance of Cast Fe-Cr-Ni Alloys to Corrosion in Oxidizing and Reducing Flue-Gas Atmospheres
Authors: Jackson J. H. , Slunder C. J. , Harder O. E. , Gow J. T. 
Published: July 2022

Abstract
Corrosion of iron-chromium-nickel castings by sulphur-bearing gases at 1800–2000 F has been investigated for the Alloy Casting Institute in a comprehensive series of tests. The sulphur was varied from 0 to 500 grains per 100 cu ft in both reducing and oxidizing flue gases. The effects of cyclic temperature fluctuations and alternately oxidizing and reducing atmospheres were also studied. Both metal loss and subsurface attack were considered in evaluating the alloys. A wide range of composition of the ternary system Fe–Cr–Ni was studied with the chromium varying from 11 to 36 per cent and the nickel from 0 to 70 per cent. Although the behavior of the present commercially important alloys deviated in specific instances, it was shown that, in general, the HE (28 per cent Cr, 9 per cent Ni), HK (26 per cent Cr, 20 per cent Ni), and the HH (26 per cent Cr, 12 per cent Ni) types had the best resistance under a variety of test conditions. The HW (12 per cent Cr, 60 per cent Ni) alloy was generally better than the HT (15 per cent Cr, 35 per cent Ni) alloy and both performed well until the sulphur content of the gas was raised to 100 grains per 100 cu ft. The HX (17 per cent Cr, 66 per cent Ni) and HU (19 per cent Cr, 39 per cent Ni) alloys were generally better than the HW and HT types; however, they too were inferior to the HE, HK, and HH types when sulphur contents were 100 grains per 100 cu ft or higher. The HF (20 per cent Cr, 10 per cent Ni) alloy originally designed for temperatures below 1600 F performed reasonably well in the tests, and at 1800 F in reducing atmosphere containing at least 100 grains of sulphur per 100 cu ft, the alloy was slightly superior to the HW and HT types. In general, corrosion in the higher-sulphur-bearing atmospheres was much less severe when the flue gas was oxidizing than when reducing.
Controlled Internal-Contour Shielded-Root Welds Without Backing Rings
Authors: Diehl Charles , Blumberg H. S. , Benz W. G. 
Published: July 2022

Abstract
Inert-gas arc welding of pipe and other weld-root beads supplemented by inert-gas inside shielding has improved greatly the deposited-metal quality and degree of penetration, but requires superlative operator skill to achieve reasonably uniform results. The process which is the subject of this paper through precise control of technique, physical dimension, and internal-shielding gas pressure, provides assurance of complete penetration, uniform root-bead inside surface free of undercutting, and desired degree of root-bead reinforcement, with only average operator proficiency. This process of controlled contour-shielded root welding designated as “K-Weld,” has been applied successfully to 9½ in OD × 1⅝ in. wall Type 347 ausfenitic utility main steam lines, and other difficult applications.
Contributions to Hydraulic Control: 4—Notes on the Hydraulic Wheatstone Bridge
Authors: Blackburn J. F. 
Published: July 2022

Abstract
Several devices based on the hydraulic analog of the Wheatstone bridge are discussed. These include bridges and derived configurations for which flow is proportional to pressure but independent of the viscosity of the liquid used, fluid sources with linear output resistances, and a bridge for the direct measurement of hydraulic conductance.
Some Notes on Dust-Sampling Equipment and Technique
Authors: Holton W. C. , Schulz E. J. 
Published: July 2022

Abstract
Battelle was introduced to the problem of dust sampling in connection with research on the combustion of pulverized coal 20 years ago. The special techniques and equipment needed for stack sampling were first developed in connection with a research investigation on spreader stokers. Subsequently, it has been elaborated and refined in various research investigations where dust measurements were needed. The equipment described has been used for dust sampling of flue gas from spreader stokers, pulverized-coal burners, and locomotives and covers a wide range of sizes of plants. This paper summarizes the results of the work at Battelle, and is presented in the hope that others may be helped by a study of this experience. It is also hoped that desirable modifications in the equipment or technique may be suggested by those reading this paper.
An Analysis of the Dynamics of Hydraulic Servomotors Under Inertia Loads and the Application to Design
Authors: Gold Harold , Otto E. W. , Ransom V. L. 
Published: July 2022

Abstract
The servomotor dealt with in this paper is a power-amplifying positioning device of the type used in such applications as control-valve positioners, flight controls, and power steering devices. The experimental and analytical study of the dynamics of the hydraulic servomotor recently completed at the Lewis laboratory develops data demonstrating the nonlinear, discontinuous nature of the dynamic response of the servomotor and includes a derivation of the basic analytical expressions for describing the response.
Quick-Starting of High-Pressure Boilers—Discussion: Controlled Starting of Steam Turbines
Authors: Reynolds R. L. 
Published: July 2022

Abstract
In order to realize the full benefits from the controlled starting of central-station units, the design, control, and operation of boilers and turbines must be closely co-ordinated. Tests have been conducted on several units to observe conditions occurring during both slow and fast starts. This paper discusses the results of these tests and points out how proper design and operation of central-station steam turbine-generator units will accomplish a material saving in starting times without sacrifice in safety or reliability.
Electric Control of Air-Flow Porosity in Plastic Sheet Materials
Authors: Suran J. J. 
Published: July 2022

Abstract
In the application of plastic sheet materials to commercial uses, one of the serious objections which often arises is the impermeability of the material to fluid flow. It is thus desirable to devise a process which permits the control of porosity in sheet materials. Such a process, as a matter of fact, has been developed by the author’s company, and is commercially known as “electroventing.” Electroventing consists of passing electric sparks through the sheet material in such a manner as to produce a desired distribution of holes, and holes of a specified size. The combination of size of holes and number of holes will determine the fluid-flow characteristics of any material. This paper deals specifically with air flow through plastic sheet materials, together with an account of how the porosity may be controlled by electroventing.
Effect of Orientation on the Mechanical Properties of Polystyrene
Authors: Cheatham R. G. , Dietz A. G. H. 
Published: July 2022

Abstract
Extruded polystyrene rod was first annealed, and then stretched hot to elongations as high as 12,000 per cent. Tests were made in tension, flexure, and torsion at temperatures ranging from 0 to 80 C. Tests included creep and relaxation as well as tests at strain and load rates ranging as high as 1.0 in/in/min and 10,000 lb per min to determine the effect of orientation upon these mechanical properties. Tensile and flexural strengths increased two to threefold, depending upon rate and temperature; torsional strength decreased; and modulus of elasticity increased moderately. Fracture changed from a sharp break to a fibrous separation. Birefringence measurements revealed marked orientation of the material, but low-angle x-ray diffraction studies revealed no “crystalline” structure.
Some Aspects of Design and Economic Problems Involved in Safe Disposal of Inflammable Vapors From Safety Relief Valves
Authors: Chesler S. , Jesser B. W. 
Published: July 2022

Abstract
The problem of disposal of inflammable vapors released from safety relief valves in petroleum refineries and similar types of units is treated in this paper. Three approaches are presented which are being employed in the design of pressure-relieving systems with the objective of reducing costs without sacrificing safety: (a) Use of diffusion equations to determine maximum concentration of gas at grade when a given quantity is discharged from a safety relief valve into the atmosphere. The solution assists in determining whether an open or closed system should be used. (b) Procedure whereby in closed systems, the sizes of discharge piping may be reduced by setting the relief valve below vessel design pressure. (c) Application of special type of safety relief valve in closed systems, in order to eliminate or reduce effects of back pressure.
The Mamba Engines in the Apollo Aircraft
Authors: Slatter B. H. 
Published: July 2022

Abstract
The installation and operation of Mamba propeller-turbine engines in a civil aeroplane, such as the “Apollo,” involved a number of new problems, some of which were fully brought to light only as a result of experience with the engines in the aircraft. The paper describes these problems and the steps which were taken to overcome them either in the design stage or, subsequently, as a result of flight experience.
Recommended Practices for the Cleaning of Turbine Lubricating Systems After Service
Authors:   Joint ASTM-ASME Committee on Turbine Lubrication
Published: July 2022

Abstract
Section I on Oil Systems of Turbines of Technical Committee C of ASTM Committee D-2 on Petroleum Products and Lubricants sponsored the paper on “Recommended Practices for the Cleaning of Turbine Lubricating Systems Before Service” presented at the 1947 ASME Annual Meeting (ASME Trans. 1948, vol. 70, pp. 363–367). In 1950 it was agreed that Section I of Technical Committee C of ASTM Committee D-2 would function as a Joint ASTM-ASME Committee on Turbine Lubrication. The Joint Committee sponsored the paper on “Recommended Practices for the Cleaning of Turbine Lubricating Systems After Service” presented at the 1950 ASME Annual Meeting. Appendix I to this paper, prepared in March, 1951, by the Joint Committee, covers “Recommended Practice for the Purification of Turbine Oils.”
Distribution of Heat-Transfer Coefficients Around Circular Cylinders in Crossflow at Reynolds Numbers From 20 to 500
Authors: Eckert E. R. G. , Soehngen E. 
Published: July 2022

Abstract
An experimental investigation using the Zehnder Mach interferometer reveals the temperature field around heated cylinders in an air stream normal to the axis. From the temperature distribution the local distribution of the heat-transfer coefficient around the cylinder circumference is obtained. The thermal boundary layers are quite thick, especially for the lower Reynolds numbers investigated and the separation occurs farther downstream than at high Reynolds numbers. Accordingly, the contribution of the stagnant region at the downstream side of the cylinder to the over-all heat transfer is low (approximately 15 per cent), and the heat flow into the upstream side is much larger than into the downstream side.
Peculiar Behavior of Steel Beams Under Dead Loads That Produce Inelastic Strains
Authors: Corten H. T. , Clark M. E. , Sidebottom O. M. 
Published: July 2022

Abstract
Inelastic deformation in metals is known to be a time-dependent phenomenon; however, the theoretical relations between load and deformation do not, in general, include the effect of time. Most of the experimental data, confirming these theoretical relations, have been obtained using screw-powered or hydraulic testing machines in which the load “falls off” as inelastic deformation occurs. Furthermore, these tests have been made without regard to the length of time necessary for inelastic deformation to cease at any given load. This investigation was undertaken to determine the effect of testing members under dead load where each increment of load could be maintained on the member a sufficient length of time until equilibrium was attained. Five statically determinate beams, four mild-steel beams of various cross sections, and one rail-steel rectangular beam were tested in a dead-load testing machine. The load-deformation diagrams were found to have a stairstep appearance, unlike the smooth continuous curves usually reported. The ultimate load-carrying capacity of the mild-steel beams was found to be considerably below that predicted by theory, and time delays of appreciable magnitude were observed for the initiation of inelastic deformation at a given load. A more stable behavior was observed for the rail-steel beam under dead load, and the experimental results were found to correlate well with theory.
Notes on a Theoretical Basis for Design of Tube Sheets of Triangular Layout
Authors: Malkin I. 
Published: July 2022

Abstract
This paper offers an approximate analytical procedure for determination of the elastic surface of tube sheets under bending. The procedure derived has been used successfully for several years as a basis for design of tube sheets of the frequently applied triangular pitch. The design formulas developed in the paper underwent experimental tests recently with satisfactory results. A description and detailed discussion of the experimental work are given also.
Automatic Flight Control—Analysis and Synthesis of Lateral-Control Problem
Authors: Bretoi R. N. 
Published: July 2022

Abstract
The author presents a method which is useful in the analysis and synthesis of the aircraft lateral-control problem. Consideration is given to establishing autopilot requirements necessary to accomplish fast, stable, and co-ordinated (zero sideslip) response. Charts are derived whereby responses of the controlled variables are plotted as a function of dimensionless time for systems represented by a second-order (e.g., simplified roll or simplified one-degree-of-freedom-yaw response), or by a third-order (e.g., simplified-co-ordinated directional control) linear-differential equation. Included is the derivation of a method for establishing autopilot requirements necessary for dynamic and steady-state co-ordination. The use of the analog computer in aiding the analysis and the effects of control lags are discussed briefly. Comparisons are made between aircraft responses calculated by means of the simplified equations, aircraft responses obtained from simulated flight recordings on the analog computer, and aircraft responses recorded during flight tests.
Analysis of Some Hydraulic Components Used in Regulators and Servomechanisms
Authors: Dushkes S. Z. , Cahn S. L. 
Published: July 2022

Abstract
Hydraulic servomechanisms have come into wide use in recent years as a result of the low inertia of hydraulic servomotors compared to electric servomotors of the same power rating. This paper discusses the theory of operation, static characteristics, and dynamic characteristics of some hydraulic components that have been used for many years in regulator applications. Previously, the dynamics of these components were not of great importance because of the slowness of the processes controlled. The important considerations were static gain and static accuracy. The dynamic characteristics have been investigated more recently as a result of the high dynamic-performance demands of servomechanism applications. Dynamics are considered from the frequency-response approach.