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RESEARCH PAPERS

J. Eng. Ind. 1968;90(1):1-12. doi:10.1115/1.3604600.

The computer program described in this paper will find the pipe size for each section of a complex piping network necessary for proper system performance within a given set of operating criteria for an incompressible fluid under steady, one-dimensional, isothermal flow conditions. Operating criteria are specified as flow and flow direction in each pipe section, pressures required or imposed at all end points of the network, and maximum allowable velocity of the fluid. The physical description of the network is given in the form of pipe lengths, quantities and types of components in each pipe section, and heights of all end points. Any network configuration, whether convergent, divergent, loop, parallel, or a combination of these, can be designed. Selected pipe sections may be fixed in size as input and the remaining sections of the network will have sizes chosen that are compatible. In addition to calculating pipe sizes and other related data, an option may be chosen to provide a basic list of material and a material ordering format.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):13-27. doi:10.1115/1.3604588.

Some three years ago, the Swiss Federal Railways introduced the prototype of a very efficient, high-power electric locomotive type Re 4/4II of the wheel arrangement Bo′ Bo′ . The locomotive weighs 80 tons overall and has a 1-hr rating of 6340 hp, and it had to be especially designed for small lateral forces between wheel and rail and good adhesion properties. In the first part of the paper, the basic theoretical problems related to the development of the mechanical part of the locomotive are outlined. The technical solutions of the various mechanical problems are described in the second part of the paper, which concludes with a few remarks on the numerous tests carried out with the completed locomotive.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):28-32. doi:10.1115/1.3604601.

The demand for improved high speed rail transportation in our growing metropolitan corridor areas has resulted in United Aircraft’s designing and building several new turbine-powered high speed trains. This paper describes some of the unique features in the suspension design permitting significant improvements in comfort and the ability of the trains to negotiate existing curves with greater speed and safety.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):33-42. doi:10.1115/1.3604602.

Railroad axle designs have been developed from an application of theoretical principles of Reuleaux combined with extensive laboratory fatigue studies supplemented to some extent by road service tests. The designer is presented with data on the effects of the complex forces acting on axles operating in railroad service. Criteria for wheel seat and axle body stresses established from fatigue tests and modified by practical considerations are discussed. The paper gives elaborate reference material for use by future investigators of axle properties and designs.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):43-48. doi:10.1115/1.3604603.

A simple, inexpensive, and rapid method of assessing cylinder and piston ring wear was developed. A small sample of the oil which lubricates the cylinder wall and piston rings was drawn off through a small hole in the cylinder wall. The sample was then analyzed spectrographically. Changes in wear resulting from changes in cylinder liner materials, fuels, lubricating oils, and other operating conditions were investigated. The method was found useful especially in cases of drastic differences in the wear rates. Selected examples of these studies are reported.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):49-53. doi:10.1115/1.3604604.

The self-cleaning oil bath air filter has been used for over 30 years for filtering intake air for large, stationary diesel engines. It has proven successful under all types of operating conditions, from the hot, sandy climate of the Southwest to the subfreezing temperatures in the North. Only recently has it been adapted successfully to locomotive applications. Previous performance standards required of locomotive engine air filters did not require the high filtering performance of this type of filter. Only since the introduction of the high horsepower diesel locomotives, where air filter standards have been considerably increased beyond the abilities of conventional locomotive filters, has the self-cleaning principle of good oil bath filtration become feasible. The purpose of this paper is to show how, through design, testing, and applications, this type of oil bath principle can be adapted to meet the critical air-cleaning needs of today’s modern locomotive engines.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):54-62. doi:10.1115/1.3604605.

A review is presented concerning the mechanics of the metal-cutting process where a continuous chip is produced with the absence of a built-up edge on the tool face. It is shown that previous theories which predicted a linear relationship of the form φ = A − B (β − α) between the angle parameters cannot be used to interpret the experimental data. The apparent linear relationships observed in some previous experimental work are thought to be due partly to the method of presentation of the results. It is suggested that a more significant combination of the angle parameters is the difference between the shear angle φ and the rake angle α, that is, (φ − α). It is pointed out that two parameters which can be used to describe the frictional conditions on the tool face are the mean friction stress and the mean normal stress. Since these can vary independently, it is thought unrealistic to group them together as a single variable. It is therefore concluded that the mean angle of friction is insufficient in itself to describe the frictional conditions on the tool face.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):63-70. doi:10.1115/1.3604606.

The two major problems in shear forming cylindrical blanks are buildup of metal ahead of the tool ring and diametral growth of the part. The process variables (feed per revolution, reduction, tool ring contour) beneficial to diametral fit unfortunately enhance buildup and vice versa; the introduction of a fourth variable, roll tilt, has been found to reduce the severity of both problems, as well as frictional drag and residual stress in the part wall. The mechanisms of axial and circumferential growth are proposed, being mainly an analogy with wedge indentation. The elastic-plastic boundary about the point of contact is calculated, as is the instantaneous velocity of extrusion. The variation of buildup with feed and reduction is shown for annealed 1100 and 7075 aluminum blanks. The effect of tool ring contour on the growth of AMS 6323 and B120 VCA parts was investigated. It was found that a sharp tool ring could cause a significant reduction of diameter and that the deep feed lines could be safely eliminated by a gradual relief at the back side of the tool ring.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):71-78. doi:10.1115/1.3604607.

A process called dynamic chip-breaking introduces a controlled low frequency vibration in the direction of the feed travel of a lathe tool. This superimposed vibration is given an amplitude such that continuous ductile chips are broken prematurely by the action of the tool. The dynamic chip-breaking process can be adjusted to give optimum values for the quality of the surface topography and free chip length. This exploratory study investigates the prospects of breaking chips from ductile materials by methods other than the conventional chip-curling type of breaker. Rational and empirical results are given which provide encouragement for additional development.

Topics: Dimensions , Vibration
Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):79-90. doi:10.1115/1.3604608.

The central burst defect, also called chevroning, in the extruded or drawn product is analyzed. A criterion for the unique conditions that promote this defect has been derived. Measures to prevent the occurrence of central burst are indicated. A major conclusion of the study is that, for a range of combinations of cone angle, reduction, and friction, central bursting is expected in any metal that can be called “Mises’ material.”1 Under such a combination (reduction, cone angle, and friction), even the most ductile material can burst centrally. The flow characteristics, described by Mises’ stress deviator-strain rate relations associated with Mises’ yield criterion, are the only metal properties needed to predict central bursting. No additional fracture criterion is associated with this failure.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):92-96. doi:10.1115/1.3604611.

The oxide protecting the surface of cemented carbide cutting tools containing both tungsten and titanium carbides is identified by electron diffraction as Ti2 O3 , which is formed during the cutting operations. This is a protective and adherent oxide which is formed as an intermediate layer between the TiC-TiO solid solution (the titanium carbide particle) and an outer layer of TiO2 . The outer layer of TiO2 is spolled off by the abrasive action of the chip and only the Ti2 O3 layer protects against welding of the chip fragments to the tool; and the protective layer retards tool wear.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):97-106. doi:10.1115/1.3604614.

The effect of load and types of finish on the stiffness of joints between machine surfaces has been investigated. An expression has been established between the normal load and the elastic stiffness of the joint. This expression has been verified experimentally. The relationship enables figures of merit (m) to be obtained for different surface conditions, different methods of machining, and different sizes of joints. A survey of industrial practice in the machining of joint surfaces has also been undertaken. This has provided a representative selection of machine finishes and enables quantitative figures to be quoted for typical joints.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):107-118. doi:10.1115/1.3604584.

A numerical method was developed to predict the local temperatures in the billet and in the tooling before the extrusion starts. The method was further extended for calculating the nonsteady-state temperature distributions during extrusion. The necessary velocity, strain rate, and strain fields were obtained from a visioplaslicity experiment. Heat generation and conduction were approximated in two consecutive steps taking place during equal time increments Δt. The temperature dependencies of the flow stress and of the thermal constants of the billet and the tool materials were taken into account, and the entire procedure was programmed in FORTRAN IV to facilitate its general use for analyzing extrusions with different extrusion ratios, materials, die angles, ram speeds, and friction conditions.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):119-126. doi:10.1115/1.3604585.
Abstract
Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):127-133. doi:10.1115/1.3604586.

This paper discusses the application of some basic elastic theory of thin circular rings used as transducers and equations generally used in the design of a surface grinding dynamometer. Octagonal strain rings and their approximation in design application to dynamometers are presented. Examples of calculations are demonstrated. The wiring diagrams of strain gages on the dynamometer are also shown. The calibration setup, curves, and equations of calibration are dealt with. The author has a dual purpose in writing this paper: He wishes to have a record of his design experience for later reference and to share some valuable information with engineers and scientists in the field.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):134-146. doi:10.1115/1.3604587.

This paper treats the problem of vibration and noise in tube-bank heat exchangers. The frequency of vortex shedding has been investigated by many authors, and their results have varied considerably. The author, in previous works, correlated these different data into a curve group of his own, and now proceeds to further analyze the problem. Results of experiments performed in a small wind tunnel are given, accompanied by typical graphs. Based on his findings, the author concludes with some design proposals for suppressing vibrations.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):147-152. doi:10.1115/1.3604589.

A technique for measuring elastic strains and the location between the plastically and elastically deformed portions of an unnotched C-ring sample is presented. Such C-rings when used to study sulfide stress cracking may incur cracks caused by both hydrogen embrittlement and stress corrosion cracking, whereas the presence of notches in the C-rings conceivably may force failure by only hydrogen embrittlement. Current studies by the authors on sulfide stress cracking include the use of both notched and unnotched C-rings.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):153-160. doi:10.1115/1.3604590.

According to a granted U. S. Patent, it is contemplated that deep water pipelines be laid on the sea floor from an inclined derrick on a lay barge without the aid of a stinger. Means are presented in this paper for calculation of required tension and inclination of pipeline at the lay barge. Charts giving necessary tension and inclination, taking pipeline stiffness into consideration, are presented.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):161-171. doi:10.1115/1.3604591.

The taut-line system measures horizontal position of a drilling vessel by using trigonometric relations with the assumption that a steel line is essentially straight from vessel to sea floor. This paper examines mathematically the accuracy of this assumption under a variety of operational circumstances. A convenient method to estimate error as a function of equipment and environment parameters is developed. Further, an on-site procedure is suggested for estimating and reducing error by use of only the taut-line system itself.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):174-185. doi:10.1115/1.3604595.

The paper presents several examples of vibrational problems recently experienced by several turbine manufacturers. These problems include stability, system critical speeds, rotor response to unbalance, and balancing of high-speed compressors and turbines. The effects of fluid-film bearings and seals, bearing pedestals, and other parts of support structure on rotor response and critical speeds are discussed. The effects of rotor stiffness, mass, and inertia distribution are presented. The paper gives a comparison between theory and practice and provides guidelines to machinery designers.

Commentary by Dr. Valentin Fuster
J. Eng. Ind. 1968;90(1):187-196. doi:10.1115/1.3604598.

The satisfactory performance of a railroad wheel depends on its ability to withstand not only the repeated stresses imposed on it by normal loads and braking conditions, but also the occasional high stresses that develop under abnormal operating conditions. The continuing trend of present railroad operating practices toward higher wheel loads and speeds has created the need for better design criteria to insure that wheel configurations are the best attainable. Under sponsorship of the American Iron and Steel Institute, the General Electric Company developed computer programs to simulate service braking and loading conditions. These were reported at the 1965 ASME Winter Annual Meeting. Now the programs have been applied to different wheel designs and the braking and loading stresses computed. The results indicate that cyclic stresses of significant magnitude may occur under different operating conditions, so fatigue concepts are important in wheel design considerations. There was no one optimum wheel design for all possible service conditions, although several configurations showed promise. A method was proposed for optimizing design for specific service conditions to safeguard against fatigue damage. To fully utilize this technique for design optimization, accurate data relating to service conditions are needed.

Commentary by Dr. Valentin Fuster

DISCUSSIONS

Commentary by Dr. Valentin Fuster

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