ORIGINAL_ARTICLE
TOWARD THE DESIGN OF AN INTELLIGENT AEROSPACE CONTROL SYSTEM
The development of control technology has been directed toward the design of more accurate, more reliable, more adaptive and responsive control systems. To accomplish such goal some artificial intelligence features should be incorporated in the design. Information identification,recognition and sorting are the corner stones of artificial intelligence. Since the only intelligent creature is the human being, therefore we have to immitate his pattern of thinking to get a job done. The present article is an attempt to define the sequence of events carried out by a human brain to perform a certain task and to identify their mathematical methodology counterparts. It is believed that following the presented approaches an intelligent control system may be constructed.
https://amme.journals.ekb.eg/article_51267_a1dd701054f421599475dc96b5698b3a.pdf
1986-05-01
1
19
10.21608/amme.1986.51267
Mohammad
Wagdi
1
Suez Canal University Faculty of Engineering at Port Fouad.+
AUTHOR
ORIGINAL_ARTICLE
A METHODOLOGY FOR INTERRELATING MANUFACTURE, CHARACTERIZATION AND FUNCTION FOR ENGINEERING SURFACES
The problem of interrelating the functional performance of a component with the manufacturing process and surface characterization has recently gained emphasis as a vital activity of research claimed by industry. The objective of this work is to present an orderly scientific approach for this problem especially in view of the "rash" of surface parameters and the few proposals for the cure. Such methodology will ultimately be a sure help to researchers in a difficult and time—consuming area.
https://amme.journals.ekb.eg/article_51750_253dd13c398ada32222d9bf55252acbb.pdf
1986-05-01
21
25
10.21608/amme.1986.51750
Sabet
Ghabrial
1
Prof., Ain Shams University, Cairo, Egypt.
AUTHOR
ORIGINAL_ARTICLE
CASE STUDY OF NOISE AND ITS REDUCTION
The paper presents a case study of noise generation and its reduction as applied to a three phase induction motor. Noise patterns of electric motors are of complex nature due to the different sources that are involved. Each of these sources can be detected from the noise spectra. These sources are mainly mechanical, electromagnetic and aero-dynamic sources. As the author was involved in research investigation dealing with the mechanical noise sources,some experimental results are also presented giving the effects of changing the bearing pre-loading,clearances and the bracket stiffness on the noise level of the test motor.
https://amme.journals.ekb.eg/article_51754_f7a2e6a0cb7b580bdf86c3883480a728.pdf
1986-05-01
27
33
10.21608/amme.1986.51754
AWNY
ATTIA
1
Professor,Faculty of Engineering, Ain Shams University,Cairo.
AUTHOR
ORIGINAL_ARTICLE
New Development in the Design and Production of Solar Collectors
New designs and production methods are used to manufacture cost effective flat solar collectors, using local materials and simple fabrication techniques. This is applied to absorber plate, collector cover, brazing, soldering and adhesive materials, the insulation and the casing as well. The different joints of the absorber are subjected to thermal cycling to determine the fatigue limit and therefore the lifetime of the absorber plate. The developed collectors are tested in a test rig to evaluate their performance and thermal efficiency
https://amme.journals.ekb.eg/article_51765_988af584e29b8bccd4a45a18a5bb330e.pdf
1986-05-01
35
42
10.21608/amme.1986.51765
A.
El-Sabbagh
1
Principal Investigator of the ,research Project.
AUTHOR
M.
Abdellatif
2
Co-Investogators of the Research Project.
AUTHOR
Z.
Ghonim
3
Co-Investogators of the Research Project.
AUTHOR
ORIGINAL_ARTICLE
New Development in the Design and Production of Solar Collectors.
https://amme.journals.ekb.eg/article_51767_03285b28ff922cb2b0bf9078aaec2529.pdf
1986-05-01
43
51
10.21608/amme.1986.51767
ORIGINAL_ARTICLE
AN INTEGRATED APPROACH TO DESIGN, MANUFACTURE AND MATERIALS SELECTION IN ENGINEERING
The introduction of a new product or changing an old model involves reaching economic decisions, making designs, selecting materials and choosing manufacturing processes. These activities are interdependent and should not be performed in isolation from each other. This is because the materials and processes used in making the product can have a large influence on its shape, cost and performance in service. If a certain design and economic analysis are based on a particular material and process it will be difficult to introduce widely different alternatives. The further the product development activities progress the more difficult it will be to consider alternative materials and processes.With the increasing pressure to produce cheaper and more reliable components and with the greater number of new engineering materials and manufacturing processes that are now available, there is a growing need for an integrated approach to economic analysis, design, and materials and process selection. The integrated approach will make it easier to achieve the optimum component that will combine the functional requirements with reliability at a competitive cost.The increasing use of computers in the various aspects of product development has made the integrated approach easier to attain. Computer aided design, computer aided manufacture, computer aided economic analysis and computerized material properties data banks are among the tools that are now available to the engineer.This paper presents a proposed integrated approach to the processes of design, economic analysis, manufacture and materials selection that are involved in introducing an engineering product. A simple case study is presented to illustrate the proposed approach.
https://amme.journals.ekb.eg/article_51770_cc9fc54268611416c5940d73b59c1d72.pdf
1986-05-01
53
61
10.21608/amme.1986.51770
MAHMOUD
FARAG
1
THE AMERICAN UNIVERSITY IN CAIRO.
AUTHOR
ORIGINAL_ARTICLE
MODELLING OF PIPING DESIGNS ON CADD COMPUTER SYSTEMS
A major piping plant design system based on a main frame CADD computer is reviewed. The basic CADD modelling concepts are explained. The steps for building, checking and reporting the plant design are then outlined.
https://amme.journals.ekb.eg/article_51773_63f6acfc0cd31af31e6b079f25eafed2.pdf
1986-05-01
63
74
10.21608/amme.1986.51773
Roshdi
Amer
1
Dr., Prof.. of Mathematics and Computer Science, Faculty of Engineering, Cairo University.
AUTHOR
ORIGINAL_ARTICLE
WALKING VEHICLES
Off-road mobility plays a key role in several development activities such as agriculture, construction,land reclamation, mining and petroleum. Despite the fact that national development in Egypt is directed towards the exploitation of the desert , no serious attention has been given to promote research work in problems of land mobility in desert areas. This paper seeks to initiate interest in research and development in off-road mobility especially on sand. It outlines some of the concepts of land mobility in nature and describes some man-made vehicles utilizing the walking concept to negotiate soft loose terrain.
https://amme.journals.ekb.eg/article_51775_4d4d25a4be463caf8b24f7d6f3224290.pdf
1986-05-01
75
85
10.21608/amme.1986.51775
Ealah
Bayoumi
1
Professor, lech. Design Dept., Cairo University,Egypt.
AUTHOR
ORIGINAL_ARTICLE
COMPUTER AIDED ANALYSIS OF COMPLEX VIBRATION SIGNATURE OF TURBOJET ENGINES
With the advent of computer's technique there has been a rapid growth in the use of microcomputers in all engineering activities. This paper outlines the important role played by a general purpose microcomputer in the analysis of the extremely complex vibration signals of the turbojet engines. The proposed system consists of an FFT analyzer and a 64 k micro computer Basically, through proper interface and specialized software, the micro-computer converts the constant bandwidth spectrum to a constant percentage bandwidth spectrum for overcoming small fluctuations in turbojet engine speed. Direct comparison of any two spectra, and comparison with predefined reference mask may be performed. The results of these comparisons are automatically printed in the fault detection program output. The paper includes practical examples illustrating, in detail , the main benefits of using the micro-computer in this domain. All the vibration spectra presented in this paper are measured on real turbojet engines mounted on the test stand.
https://amme.journals.ekb.eg/article_51782_54375e90ce6e9f86696cb1f29d704615.pdf
1986-05-01
1
12
10.21608/amme.1986.51782
A.
MAHER
1
Maj.Gen. Prof., Chief, Branch of General Mechanical Engineering, Military Technical College, Cairo, Egypt.
AUTHOR
S.
KOSSA
2
Col. Dr., Aeronautical Department, Military Technical College, Cairo, Egypt.
AUTHOR
M.
KADDAH
3
Col. Dr., Aeronautical Department, Military Technical College, Cairo, Egypt.
AUTHOR
M.
EL-HUSSEINY
4
Col., Engineer, Egyptian Airforce.
AUTHOR
ORIGINAL_ARTICLE
LATERAL VIBRATION OF CANTILEVERS ON VISCOELASTIC FOUNDATIONS
Lateral vibrations of uniform cantilevers resting on viscoelastic foundations are investigated. Effect of foundation parameters and a follower force applied at the cantilever free end, on natural frequencies and vibration stability is studied. The system governing equations reduced to a dimension less form, is solved using variational method, with three modes of vibrations taken into account. The second and third natural frequencies are shown to increase with the increase of either the foundation elastic and shear rigidities or the applied external tensile force. The first natural frequency increases with increasing the foundation elastic rigidity, while it decreases with the increase of the foundation shear rigidity and/or the tensile follower force, till it vanishes indicating vibration instability. Regions of stable vibrations are determined when the cantilever is subjected to a tensile or compressive follower force. Results obtained can be used for design purposes to determine the foundation parameters that should be guaranteed for stable vibrations when a certain follower force is applied to the beam, or alternatively to determine the limits to be imppsed on this force when the cantilever is mounted on a viscoelastic medium of known parameters.
https://amme.journals.ekb.eg/article_51793_06da86bba115919ac9909fe16c14d1e4.pdf
1986-05-01
13
22
10.21608/amme.1986.51793
S.
KASSEM
1
Associate Professor, Mechanical Design and Production Department, Faculty of Engineering, Cairo University, Cairo, Egypt.
AUTHOR
ORIGINAL_ARTICLE
EXPERIMENTAL INVESTIGATION OF NONLINEAR AERODYNAMIC DAMPING OF PARTIAL AIRPLANE ASSEMBLY
Low speed wind tunnel testing of partial assemblies of aircraft fuselage and its horizontal tail surfaces are performed using a special dynamic stability balance. Experiments were aimed for investigating the effects of airplane aerodynamic components on the nonlinear behaviour of pitch damping in a range of moderate angles of attack. The function of balance is based on the method of forced pitch oscillations of geometrically similar model in straight parallel air flow. Damping coefficients are determined from analysis of motion records. Measurements are performed in range of flow velocities at different oscillation frequencies. Obtai-ned results proved linear dependence of damping derivative on flow velo-city, and independence of the nondimensional damping in pitch derivate on the oscillations nondimensional frequency. Strong nonlinearity in the dependence with angle of attack is observed, which is related to the creation and seperation of vortices on fuselage sides. The research pro-ved strong favourable contribution of quasi-slender fuselages to the nonlinear character of aerodynamic forces of their aircraft assemblies.
https://amme.journals.ekb.eg/article_51794_e1c4b4b0c921d5eba8e67dd79eae61ca.pdf
1986-05-01
23
30
10.21608/amme.1986.51794
O.
ABDELHAMID
1
Department of Aeronautical Engineering, Military Technical College, Cairo, EGYPT.
AUTHOR
ORIGINAL_ARTICLE
ABOUT THE LUMPED PARAMETER APPROACH TO HYDRAULIC LINE MODELLING
This paper deals with the development of simple lumped models of hydraulic transmission line. The models take into consideration the effect of viscous damping, fluidinertia, fluid compressibility and elas-ticity of line material. The developed models are one-directional;the fluid speed and pressure are thought of as averaged quantities over the cross section of the line. The simplicity of models result from the sepe-rate evaluation of the effect of the above mentioned parameters. The vali-dity of the models is discussed onthe bases of the comparison of the step and frequency responses of models with experimental results.
https://amme.journals.ekb.eg/article_51797_79e6be9c2b54e87c22aff3f595043437.pdf
1986-05-01
31
46
10.21608/amme.1986.51797
Calal
RABIE
1
Lecturer, Chair of Aircraft, Military Technical College, Cairo.
AUTHOR
ORIGINAL_ARTICLE
A GENERAL PROCEDURE FOR INVESTIGATING THE INSTANTANEOUS KINEMATICS OF MULTI-LOOP MECHANISMS
The screw theory is applied to the study of the instantaneous kinematics of multi-loop mechanisms. A general procedure for investigating the instantaneous kinematics of multi-loop mechanisms is introduced using only better interpretation and implementation of the two fundamental laws of instantaneous kinematics; series and parallel laws. The procedure is applicable to any mechanism specially to that type of practical mechanisms with pre-specified actuated joints. It neither requires special cases to be identified nor requires any more laws to be introduced. Numerical example is presented.
https://amme.journals.ekb.eg/article_51800_690b0c4d50b581a5bef3d9834e168ea0.pdf
1986-05-01
47
55
10.21608/amme.1986.51800
MAHER
MOHAMED
1
Lecturer, Mechanical Engineering Department, Faculty of Engineering and Technology, El-Minia University, El-Minia, Egypt.
AUTHOR
ORIGINAL_ARTICLE
ANALYSIS OF TRACKED VEHICLES TURNING ON LEVEL TERRAINS
Steerabilityy represents one of the principal measures of tracked vehicles mobility. Study of turning problems provides the possibility of steerability prediction. Several papers on the subject were concerned mainly with the kinematic response of vehicle during turning, taking into consideration the track slip. This paper deals with turning from the point of view of the required forces on tracks for a specified turning process and accordingly, the track slip was neglected. That helps in determining the required power to be developed by engine for turning, which is essential for the selection of engine and vehicle configuration in case of a new design, or for evaluation and development of an existing design. A mathematical model for the kinematic and dynamic parameters neglecting the track slip, was developed through a theoretical analysis. The equations of vehicle motion during turning were derived and solved for the required forces on tracks, limited by the adhesion conditions with ground. Since the average speed of modern tracked vehicles has been augmented remarkably, the model was developed for the general case of nonuniform turning where the effect of inertia forces was considered. The influence of speed on turning parameters was investigated numerically for a selected vehicle on a computer program applying the theorectically derived model. The simulation results with discussion and conclusions are presented.
https://amme.journals.ekb.eg/article_51802_d33e8ae87a4229c47e926a9570239bc0.pdf
1986-05-01
57
68
10.21608/amme.1986.51802
ABDEL MEGID
ZIDAN
1
Col. Dr., Department of Tanks, Military Technical College, Cairo EGYPT.
AUTHOR
ORIGINAL_ARTICLE
ANALYSIS OF BARREL VIBRATION DURING FIRE
The study of barrel vibration is important for the performance of firing Weapons .In this paper the finite element method is used for modelling the barrel and determining its characteristics .A complete analysis of the course of affecting forces on barrel during the whole period of action is carried out for defining them. The calculation procedure is programed for easy analysis of barrel response. The influence of barrel vibration on successive uency analysis of the recorded details is carried out. The comparison between muzzle trajectory at different modes of fire. A real time analysis and a frequency analysis of the recorded details carried out.The comparison between both theoretical and experimental results proved the accuracy of the proposed model.
https://amme.journals.ekb.eg/article_51812_0aabc66bc976c2d7d4bff3b2f405623d.pdf
1986-05-01
69
80
10.21608/amme.1986.51812
M.
ABO ELKHAIR
1
MTC, M.Sc, Chair of Weapons an Ammunition.
AUTHOR
M.
ELNAGGAR
2
MTC, Ph.D, Chair of Weapons and Ammunition.
AUTHOR
A.
BASSIOUNI
3
MTC, Ph.D, Chair of Mechanics and Elasticity.
AUTHOR
ORIGINAL_ARTICLE
AUTOMATIC NORMAL MODE TESTING
https://amme.journals.ekb.eg/article_51815_bfc6c76e55b0f7cc4ab7556b19a4e627.pdf
1986-05-01
81
87
10.21608/amme.1986.51815
K.
Zaveri
1
(M.Phil. DC)
AUTHOR
ORIGINAL_ARTICLE
ANALYSIS OF ANISOTROPIC ELASTIC FOUNDATION UNDER CONCENTRATED FORCES
A detailed analysis for anisotropic semi-infinite medium, under the effect of concentrated forces,is given. The analysis deals with some kind of anisotropy, in which the material properties are cylindrically orthotropic. The effect of a line concentrated load on a semi-infinite cylindrically orthotropic foundation is treated. The radial and tangential displacement components are chosen to satisfy the equilibrium, compatability and boundary conditions of the problem. Using the generalized Hookels law, the assumed displacement functions leads to a simple radial stress, which occurs in such kind of problems, as found in literature. The effect of anisotropic constant on radial and tangential displacement components is discussed. Variations of displacement components along the radial and tangential directions are given.
https://amme.journals.ekb.eg/article_51820_750e793e4fee101463dad8c19d777390.pdf
1986-05-01
1
12
10.21608/amme.1986.51820
E.
EL-SOALY
1
Brig. Dr., Department of Mechanics and Elasticity, Military Technical College, Kobri- El Kobba, Cairo, Egypt.
AUTHOR
ORIGINAL_ARTICLE
MDDELING OF GEAR TOOTH BY THICK PLATE
The recent approach of Bergan and Wang for the shear inclusion in plate deformation is used in nodeling the gear lOoth as a cantilever plate. Using Rayleigh-Ritz method a solution is obtained and compared with other models.
https://amme.journals.ekb.eg/article_51823_c130ba854791320d79cadd5857929a3b.pdf
1986-05-01
13
23
10.21608/amme.1986.51823
Kamal
Hassan
1
Dr. Eng., Ministry of Higher Education, Cairo, Egypt.
AUTHOR
Henry
Busby
2
Ass. Prof., The Ohio State University, Columbus, Ohio.
AUTHOR
Donald
Houser
3
Prof., The Ohio State University, Columbus, Ohio.
AUTHOR
ORIGINAL_ARTICLE
CREEP AND FRACTURE OF NICKEL-ALUMINIUM ALLOY
Creep and fracture behaviour of Nickel-Aluminium alloy with Aluminium concentration of 7.13% was investigated at 1073 K over a range of stresses from 40 to 115 MPa. The alloy consists of solid solution matrix strengthened by Ý (Ni3 AL) particles. High precision constant stress creep curves have been obtained and analysed in terms of creep rate and fracture life. Over most of the transient and steady creep curve, the strain at any instant can be described accurately as :
Ɛ=Ɛ0+Ɛp (1-e-mt) + Ɛst.
where Ɛo is the instantaneous strain on loading, Ɛp the total transient strain, Ɛs the steady-creep rate, and m a constant relating to the rate of exhausion of transient creep. Analysis of the tertiary creep curves in terms of particle coarsening has been made and compared with the experimental results and also with different equations based on strain dependent damage. The results of the analysis combined with the scanning electron microscope observations of the fractured surfaces have shown that damage in the form of intergranular cavitation and cracking is the most probable mechanism responsible for creep fracture in this case.
https://amme.journals.ekb.eg/article_51832_a60e6cd35210d394b0742ce6f50aed74.pdf
1986-05-01
25
34
10.21608/amme.1986.51832
MOHAMED
ABDOU
1
Associate Professor., Mechanical Engineering Department, AL-Azhar University, Nasr City, Cairo, Egypt.
AUTHOR
ORIGINAL_ARTICLE
INHOMOGENEOUS DEFORMATION ZONE IN TENSILE SPECIMEN
This paper analyses the relation between longitudinal- and cross sectional-strain for plastic inhomogeneous deformation at the neck of tensile test specimen. The geometry of neck nrofile is described according to instantaneous measurements of diameters along the axis of the test specimen. An improved neck measuring instrument (MI) is proposed for ploting the neck profile during the test. Evaluating formulae corres-ponding to the proposed MI are deduced. The results of the proposed evaluating formulae for describing the mechanics of neck deformation are compared to those found elsewhere. The validity of the proposed method of evaluation is verified analytically and experimentally.
https://amme.journals.ekb.eg/article_51834_39703e2bcf24a459caf4b949f39940bf.pdf
1986-05-01
35
42
10.21608/amme.1986.51834
SAMIR
EL-NEMER
1
Dr. Eng. Samir Kassem El-NEMER; Lecturer at Faculty of Engineering and Technology, Port Said, Sues Canal University.
AUTHOR
ORIGINAL_ARTICLE
GEAR NOISE MEASURING TECHNIQUE
The paper presents a part of work carried out for the Degree of Ph.D. on noise of gear of circular arc tooth profile.For this purpose an anechoic room has been built in the Military Technical College to measure the variation of noise level of gears of circular arc tooth profile running at different speeds and transmitting different loads. Overall noise levels were picked up by 1/2 inch condenser micro-phone and recorded by tape recorder. The readings were then analysed and the largest frequency component were determined.
https://amme.journals.ekb.eg/article_51835_ccd2034b7c2d1d9b3174f127c7a4c58d.pdf
1986-05-01
1
12
10.21608/amme.1986.51835
SH.
ABDELAZI
1
Ph.D. Candidate, Machine Design Dept., Military Technical College, Cairo, EGYPT.
AUTHOR
N.
GADALLAH
2
Lecturer, Machine Design Dept., Military Technical College, Cairo, EGYPT.
AUTHOR
ORIGINAL_ARTICLE
OPTIMAL CONTROL OF A TURBOJET ENGINE A DYNAMIC PROGRAMMING APPROACH.
This paper discusses the application of dynamic programming techniques in the domain of turbojet engine control system design. Based on a known detailed model of a by-pass double-spool turbojet engine, derived in previous works, we obtained an optimum control law governing the acceleration of the engine. The work discusses the adaptation of dynamic programming techniques to the specified problem. A detailed analysis of the problem characteristics is included and a discussion of computer implementation requirements is presented.
https://amme.journals.ekb.eg/article_51837_83fbadb13888d1723c7ed9a683868b55.pdf
1986-05-01
13
26
10.21608/amme.1986.51837
MOHTASSEM BILLAH
KADDAH
1
AERONAUTICAL DEPARTMENT - MILITARY TECHNICAL COLLEGE CAIRO - EGYPT.
AUTHOR
ORIGINAL_ARTICLE
DESIGN PARAMETERS CF THE MULTI-BOLTED JOINT.
The multi-bolted joint is commenly used in various machine design problems, such as the joint between the base and the culumn of the milling machine. The paper deals with the design parameters of the multi-bolted joint and their effect on the joint stiffness. An optimal mathematical method to calculate the static joint stiffness has been chosen. The effect of the bolt diameter, number cf the bolts to be used, and thickness of the members to be jointed on the magnitude Of the normal stiffness of the joint have been anal,Ised and discussed. A proposed design diagram for the bolted joint loaded with the normal external force are developed and it can be simply used.
https://amme.journals.ekb.eg/article_51838_b39f266daf250d1d963f14140a8ef30b.pdf
1986-05-01
1
11
10.21608/amme.1986.51838
GABER
SHEHA
1
Lecturer, Department of Production Engineering and Design, Faculty of Engineering and Technolocy , Menoufia University, Shebin El-Koom, Egypt.
AUTHOR
ORIGINAL_ARTICLE
THE MOTION EFFECT ON THE (EHD) BEHAVIOUR OF CAM MECHANISMS
The scuffing behaviour is one of the main fac.torsassociated with the performance of cam follower mechanism. The objective of the present work is to study the scuffing phenomena through the kinematic analysis of various effectsof different types of motion on the elastohydrodynamic (EHD) lubrication properties in cam mechanisms. The contact points of cam follower surfaces at which flash temperature reaches maximum due to poor lubrication are specified. An examination had been developed at each point to investigate the possibility of scuffing occurance and mechanisms failure.
https://amme.journals.ekb.eg/article_51840_910760efb2b1c0fa69f2cb0d4d33de02.pdf
1986-05-01
13
20
10.21608/amme.1986.51840
S.
GHONEAM
1
Lecturer; Ph.D, Mechanical Engineering & Machine Design Dept., Faculty of Engineering & Technology, Menoufia University., Shebin El-Kom . EGYPT.
AUTHOR
ORIGINAL_ARTICLE
A REVIEW OF SOLID PARTICLE EROSION; SELECTED PUBLISHED INFORMATIONS
Erosion caused by solid particles, such as sand grains, can occur under a variety of service conditions. Probably the most important erosion problems which occures in industry are those connected with gas turbines powering helicopter and equipment used in cracking oil. Solid particle erosion received little disciplined study before about 1960. The scope of the present work is to review selected published informations on solid particle erosion in order to show how far the previous investigators have been succeeded in explaining the mechanisms of erosion and evaluating the dependance of erosion on experimental data.
https://amme.journals.ekb.eg/article_51843_ae8d648d09a39aecfd4aa534de6097dd.pdf
1986-05-01
21
33
10.21608/amme.1986.51843
F.
BASSILI
1
Lecturer, University of Suez Canal, Faculty of engineering for Petrol & Mining, Suez, Egypt.
AUTHOR
W.
JONES
2
Reader, University College London, Faculty or Engineering, London, U.K.
AUTHOR
ORIGINAL_ARTICLE
FATIGUE OF RAILWAY STEEL CLIPS
Steel clips made from modified 5160H spring steel are used to hold down railway rails to sleepers. The clip has shown fatigue failure, and the cracks are so aligned as to indicate mixed mode loading, i.e. torsion and tension; the latter due to bending.Specimens has been tested for torsional and push-pull fatigue. Biaxial fatigue theories are used to achieve design conclusions in order to avoid fatigue failure of the clip.
https://amme.journals.ekb.eg/article_51845_71615e143bbeb1c5d732d2aed3264066.pdf
1986-05-01
35
46
10.21608/amme.1986.51845
M.
IBRAHIM
1
Dept. of Machine Design, Military Technical College, Cairo-EGYPT.
AUTHOR
M.
GABRA
2
Dept.of Aeronautical Engineering. Military Technical College, Cairo-EGYPT.
AUTHOR
ORIGINAL_ARTICLE
BEHAVIOUR OF ALUMINIUM- MAGNESIUM ALLOY UNDER ROTATING BENDING FATIGUE TESTS
Behaviour of materials under repeated application of loads of varying magnitude is an important problem in design aspect. Most structures and machine parts "which are made of aluminium - magnesium alloy " are subjected to more or less random fluctuations of loads. Therefore, the main purpose of this work is to obtain data which can be used as a guide for predicting the behaviour of aluminium - magnesium alloy in service. Presented here are the results of endurance fatigue tests for the material. The specimens have been subjected to rotating bending stress, and also the staircase testing procedure was followed to determine the endurance strength of the material. Two-step tests for cumulative fatigue damage were conducted to the material. A comparison between the experimental results with the cumulative fatigue damage rules is made. An agreement for the isodamage rule with the experimental results. The experimental results indicated that the amount of damage is more than unity for low-high sequences and less than unity for high-low sequences with the same different of magnitude of damage than unity.
https://amme.journals.ekb.eg/article_51850_b1f3cf3765a35bcc20b4183924e42022.pdf
1986-05-01
47
55
10.21608/amme.1986.51850
Mohamed
Kenawy
1
Assistant Professor, Mechanical Design Dept., Faculty of Engineering and Technology Mataria, Helwan University, Cairo, Egypt.
AUTHOR
Mohamed
Abd El-Wahed
2
Assistant Lecturer, Mechanical Design Dept., Faculty of Engineering and Technology Mataria, Helwan University, Cairo, Egypt.
AUTHOR
ORIGINAL_ARTICLE
Low Cycle Fatigue and Crack Initiation Prediction at the Root of a Notch
Conventional fracture mechanics have made it possible to quantify the slow propagation of a crack subjected to cyclic loadings,as well as the fracture phase. Unfortunately,it is still impossible to quantify seperately the initiation phasc of a crack. Fatigue crack initiation was investigated by testing 2124T351 Aluminum alloy with 12 mm thick ASTM compact tension specimens having various notch-root radii between 0.1 and 10 mm . Crack initiation was detected by electric potential method. In order to calculate the number of cycles required to initiate a crack,notch root behavior was investigated through two main approaches: Elastic and Elastoplastic analy-sis of stress concentration under fatigue.The effect of confined plasticity at the notch root was analysed. Consideration of this plasticity would ameliorate to a great extent the crack initiation analysis and prediction.
https://amme.journals.ekb.eg/article_51856_f8ccbe2e0dd5a88d3ca5105cc63c4930.pdf
1986-05-01
67
78
10.21608/amme.1986.51856
M.
GABRA
1
Lecturers,Dept. of Aeronautical Engineering,Military Technical College,CAIRO.
AUTHOR
G.
RABIE
2
Lecturers,Dept. of Aeronautical Engineering,Military Technical College,CAIRO.
AUTHOR
M.
IBRAHIM
3
Lecturer,Dept. of Machine Design,Military Technical College,CAIRO.
AUTHOR
ORIGINAL_ARTICLE
A STUDY OF ENGINE WEAR AS INFLUENCED BY LUBRICANT CONDITIONS
In this work a comprehensive review of the basic lubrication mechanisms that would exist in engine lubrication will be discussed. The subsequent effect of lubricants (new or used) on engine wear is also, herein, summarized and followed by a description of test procedure on a specially constructed test machine to analyse wear under dry or lubricated contacts. Results have also been presented to compare the effect of change in oil properties and the presence of contaminants after prolonged time of use on the wear rate. A detailed theoretical study is also given to dynamic performance. The dimensional changes in applying hydrodynamic lubrication theories frictional resistance, oil flow rate and side be fully computed and analysed. assess the effect of engine wear on the hydro-in crank bearings due to wear have been considered and their effect on the load carrying capacity, leakage and maximum hydrodynamic pressure could
https://amme.journals.ekb.eg/article_51865_2b06f391186ebc49f110075b0f23c078.pdf
1986-05-01
79
91
10.21608/amme.1986.51865
M.
MOKHTAR
1
Professor., Department of Mechanical Design & Production., Faculty of Engineering, Cairo University.
AUTHOR
M.
RADWAN
2
Associate Professor., Department of Mechanical Design & Production., Faculty of Engineering, Cairo University.
AUTHOR
Z.
SAFAR
3
Professor., Department of Mechanical Power Faculty of Engineering, Cairo University
AUTHOR
M.
KHADER
4
Professor., Department of Mechanical Power Faculty of Engineering, Cairo University
AUTHOR
ORIGINAL_ARTICLE
PHOTOELASTIC ANALYSIS OF DRY LINE CONTACT PROBLEM UNDER COMBINED LOADING
This study concerns the photoelastic analysis of dry contact between a cylinder and a plane under combined loading. Both static and dynamic cases are experimentally dealt with. A test rig is specially designed to collect essential data within and in the vicinity of the contact area. Data obtained have been analysed to estimate the contact area, normal and tangential stress distributions, coefficient of friction and the position of maximum shear through the contact . Results are compared with theoretical and experimental values(previously published) by other authors. The comparison of dynamic with static experimental results clarifies the angle of assymmetry of maximum shear stress fringes corresponding to the angle of friction.
https://amme.journals.ekb.eg/article_51871_04cb6ade6d5999e6625d6864d15516fb.pdf
1986-05-01
93
102
10.21608/amme.1986.51871
SH.
EL KORDY
1
M.Sc., Mech.Eng, M.T.C.
AUTHOR
A.
EL SANABARY
2
Lecturers, M.T.C, Kobry EL Kobba, Cairo-EGYPT.
AUTHOR
N.
GADALLAH
3
Lecturers, M.T.C, Kobry EL Kobba, Cairo-EGYPT.
AUTHOR
ORIGINAL_ARTICLE
APPLICATION OF HERTZ ANALYSIS TO THE CONTACT OF SURFACES COVERED BY SOFT METAL FILMS
Understanding of the behaviour of Hertzian contact is basic to the design of the tribological contacts such as rolling bearings, gears and came. This paper describes an investigation of the static contact between a steel ball on a lead plated steel flat. Both the normal approach of thes surfaces and their area of contact have been measured as functions of normal loads and the the thickness of the lead film. It is shown that at high loads all the coated surfaces behaved elastically. It is also shown that the Hertz solution can be applied to calculate both normal approach and contact area when using the suitable value of the elastic modulus. An imperical equation has been given to calculate the equivelent elastic modulus which is shown to be function of both, elastic properties of the contacting surfaces together with the film thickness.
https://amme.journals.ekb.eg/article_51877_b3c5582b55655d7c81a8bfb3b4cc6763.pdf
1986-05-01
103
110
10.21608/amme.1986.51877
T.
El-Shafei
1
Lecturer., Military Technical College, Cairo, Egypt.
AUTHOR
ORIGINAL_ARTICLE
PRODUCTION OF FERRITIC AND PEARLITIC GRADES OF SPHEROIDAL GRAPHITE CAST IRON BY THE INMOULD PROCESS
The effect of inoculation efficiency and casting thickness on the final as cast structure of ductile iron castings was investigated. Four stages medium size ,testing cluster weighting 56 Kg. was utilized to determine the required conditions for production of as cast ferritic structure in thin section castings. Each stage contained wedge shaped specimen with variable thickness from 2mm up to 25mm. Time elapse between inoculation and complete filling of each stage varied from 14 seconds for the first level to 56 seconds for the fourth level. Low magnesium ferro-silicon alloy 5% Mg(VL 63) was used as inoculant with average grain size 3-5mm. Inoculation was performed directly inside the mould utilizing special reaction chamber located in the runner. Microstructure observation and hardness tests were carried out on the obtained as cast structure of the four stage wedges. The chilling depth in each level was evaluated. A relation between time elapse from inoculation till solidification start and final as cast structure was established. The impact of casting thickness on the as cast structure was found to be less than that of inoculation efficiency. Ferritic and Pearlitic grades of spheroidal graphite cast iron can be obtained by control of inoculation parameters in case of inmould process
https://amme.journals.ekb.eg/article_51880_507ee40bf3f0d504992d40ff39fa3467.pdf
1986-05-01
1
14
10.21608/amme.1986.51880
B.
ELSARNAGAWY
1
Department of Materials and Processes, Military Technical College, Cairo,EGYPT.
AUTHOR
M.
SALLAM
2
Department of Materials and Processes, Military Technical College, Cairo, EGYPT .
AUTHOR
ORIGINAL_ARTICLE
PROPOSITION OF DEVELOPMENT OF A WELDED STRUCTURES MANUAL TO HELP IN PROMOTING OF THE ARAB WELDING INDUSTRY
The intent of this paper is to propose a scheme of work to deal with the preparation of a proposed manual to aid in sorting out the present discrepancies currently facing the Arab welding industry. Therefore, the aim of the proposed welded structures Manual is to unify the different schools currently applied within the Arab welding industrial sectors. The task would therefore be to propose a preformat for the evolution of the Arab Welding Code of Practice and the Arab Welding Standards and Specifications. The conclusions expected may be summerized in the following main points :-As a result of the unification of the different codes of practice and the evolution of the Arab Welding Code of Practice, better welding efficiency and high productivity is expected.-The cost of production will be very much reduced due to the evolution of the Arab Welding Code. -The speed in the line of production will be increased, thus this code will have a major impact on economic and engineering aspects. -The proposed code must provide the Arab designers, the Arab fabricators and the owners with a basic tool to decide on whether and when repairs must be carried out. Hence better efficiency and better earning capacity can be achieved.
https://amme.journals.ekb.eg/article_51888_2d9ed5debbdaf3a9dc4a5eec990cbf98.pdf
1986-05-01
15
25
10.21608/amme.1986.51888
MOUSTAFA
EL-GAMMAL
1
Prof,Dr,Eng, PROFESSOR OF TECHNOLOGY AND SHIPBUILDING, ARAB GULF ACADEMY FOR MARITIME STUDIES, BASRAH, IRAQ.
AUTHOR
ORIGINAL_ARTICLE
EFFECT OF ALLOYING ELEMENTS ON PRODUCTION OF DUPLEX PREFORMS WITH COMPOSITE PROPERTIES
An experimental investigation was conducted to produce cylindecical powder preforms with high hardness at rim and enough toughness at core to suite the requirements in gearing systems. The difference in properties was achieved only by the different alloying additives. A special composite die was designed to perform the partial compaction of either rim or core beside. the final compaction of the specimen as a whole. Preforms were produced by 600 MPa compaction pressure and 2 hours sintering under H2 atmosphere at 1200°C. A series of experiments were carried out using different compositions to achieve the required difference in properties between the core and the rim and secure enough bond and adhesion between them. A mixture consisting of Fe + 5% Cu in the core and Fe + 2% C + 5% Cu+ 6% Ni in the rim yielded a compact allowing a shear strength value of 225 N/mm2 at the interface, hardness value of 412 HV in the rim, hardness value of 125 HV, in the core, and an overall sintered density of 7.26 gm/cm3. Another series of experiments were carried out using manganese as alloying additive beside copper and nickel to improve the properties at the interface.A mixture consisting Fe + 5% Cu in the core and Fe + 2% C + 2% Cu+ 6% Ni + 2% Mn in the rim yielded a compact allowing a shear strength value of 250 N/mm2 at the interface, hardness value of 232 HV in the rim, hardness value of 112 HV, in the core and an overall sintered density of 7.28 gm/cm3.
https://amme.journals.ekb.eg/article_52030_4e7b485caa6c7b35eaeb69b484a7cc56.pdf
1986-05-01
27
40
10.21608/amme.1986.52030
M.
SALLAM
1
Department of Materials and Processes, Military Technical College,Cairo.
AUTHOR
ORIGINAL_ARTICLE
THERMAL PROPERTIES OF CO2 SILICATE MOLDS/CORES
Thermal properties of foundry sand determine to a great extent the rate of heat extraction from castings and thus influence their quality. Thermal properties of interest of C02 silicate molds are thermal conductivity, specific heat, heat accumulation factor and thermal diffusivity. The effect of variation of % of sodium silicate, gassing time and ramming strokes on aforementioned thermal properties of foundry sand have been reported. To know the independent, interactive and higher order effects of process parameters on the yield, experiments were planned according to central composite rotatable design with half replicate. The adequacy of the model was tested using analysis of variance and accuracy by experimental data. Finally, it has been concluded that such studies would be helpful to control the properties of molds/cores and thereby the quality of castings.
https://amme.journals.ekb.eg/article_52035_4731cfa7619e9d1705d51f5295ac52e4.pdf
1986-05-01
41
50
10.21608/amme.1986.52035
S.
Mishra
1
Deputy Manager Management Services Dept. Hindustan Antibiotics Ltd., Pimpri, PUNE-411 018 (INDIA)
AUTHOR
V.
Jain
2
Asst. Professor Mech. Eng. Dept, Indian Institute of Technology, KANPUR-208016 (INDIA)
AUTHOR
ORIGINAL_ARTICLE
THE WEAR CHARACTERISTICS OF SOME ALUMINIUM-SILICON EUTECTIC-BASE ALLOYS.
The wear behaviour of the aluminium-eutectic base alloy is examined along with the modified entectic alloys containing varying copper additions and a constant amount of Mg and Ni which are used to improve the strength of the alloys. The wear tests are carried out for the various alloys either in the as-homogensized state or after aging treatment, at constant sliding speed and different loads. The results are examined in order to determine the optimum condition for wear resistance.
https://amme.journals.ekb.eg/article_52036_f3160f6fed63489c2247d2e8fa520535.pdf
1986-05-01
51
59
10.21608/amme.1986.52036
M.
SAmI
1
Welding electrode factory.
AUTHOR
S.
IBRAHIM
2
Met. Dept, Faculty of Pet & Mining Eng., Suez Canal University, Suez.
AUTHOR
ORIGINAL_ARTICLE
LIQUID PHASE SINTERING USING SUPER ALLOYS
The outhors are working on a project sponsored by the supreme council of Universities to deal with the subject of duplex powder preform forgings. As a part of its relevant program, the effect on hardness and tensile strength of liquid phase sintering was investigated. For such a study, specimens in circular and rectangular cross sections were produced from EMP 4607 steel powders with the additions of some different brazing alloy powders with an amount of 3.5%. Similar specimens were also prepared from DT 4607 steel powder only. Brinell hardness values were measured for cylindrical specimens. Tensile tests were performed by making use of the specimens with rectangular cross sections. The effect on mechanical properties of both sintering time and liquid phase sintering was observed.The results obtained at this stage were discussed with the aid of micro-structures examination.
https://amme.journals.ekb.eg/article_52041_402340de9e6986d95cc6cf0a6ecfac12.pdf
1986-05-01
61
69
10.21608/amme.1986.52041
M.
Hamoud
1
Mechanical Engineering Department,A1-Azhar University,Cairo,Egypt.
AUTHOR
M.
Abd-Elatif
2
Mechanical Engineering Department,A1-Azhar University,Cairo,Egypt.
AUTHOR
G.
Said
3
Mechanical Engineering Department,A1-Azhar University,Cairo,Egypt.
AUTHOR
M.
Negm
4
Mechanical Engineering Department,A1-Azhar University,Cairo,Egypt.
AUTHOR
ORIGINAL_ARTICLE
APPLICATION OF CRACKABILITY PARAMETERS TO EVALUATE TEST RESULTS OF SELF-RESTRAINED CRACKING SPECIMENS
Weld cracking susceptibility, or simply, the weldability, is a most significant problem in utilizing high strength steels. A number of formulas have been suggested and available for the prediction of the weldability using chemical composition. Those formulas calculate various weldability criteria such as the hardness, the ductility and the amount of cracking in the heat affected zone. Ito and Bessyo have proposed crackability formulas (Pc and/or Pw) including chemical composition, weld metal hydrogen centent, plate thickness and stress-intensity. In their work they have used the y-groove restraint cracking test specimen. In this investigation, an attempt was made to evaluate test results of Tekken, Lehigh and CTS using the proposed parameters. Structural steels of different chemical composition and thickness were welded, using electrode diameters from 3.25 to 5.0 mm. Welding current was varied from 120 to 220A and welding speed from 8 to 20 cm/min. Preheating temperature range was from 25 to 150°C. Cracks were detected and evaluated in three to four transverse sections of test welds. Test results obtained using Tekken, Lehigh and CTS crackability tests are .compared and evaluated. Critical cooling time between 800 and 500°C was determined for each test condition using crackability parameters Pc and/or Pw at which crack formation starts in the welded joints. Simultanously, the abovementioned tests were ranked from severity point of view.
https://amme.journals.ekb.eg/article_52045_5df5bd2504ce961be9f53acf72b77545.pdf
1986-05-01
71
82
10.21608/amme.1986.52045
M.
EL-HEBEARY
1
Associate Professor, Department of Mechanical Design and Production Engineering, Faculty of Engineering, Cairo University, Cairo, Egypt.
AUTHOR
ORIGINAL_ARTICLE
WEAR PROPERTIES OF AUSTEHPERED ALLOYED DUCTILE CAST IRON GEARS
Recently austemopred ductile cast iron is utilized for production of gears in automotive industry in order to reduce the production costs. The problem of low hardenability of unalloyed ductile cast iron dictated the use of alloyed ductile cast iron. The present work is devoted to investigate the wear properties of austempered alloyed ductile cast iron 2% Ni, 0.5% Mo which is chosen to replace forged gears produced from carburized and hardened steel DIN 34 17220. The programme of wear tests is based on the comparison between the performance of austempered alloyed ductile cast iron and steel DIN 34 17220. Disc type wear test specimens with diameter of 40 mm and thickness 10 mm were made from alloyed ductile cast iron and from the steel. The tests were carried out at dry slidinft condition, wet sliding condition, and wet sliding plus 10% rolling. The results of wear tests showed that the wear characteristics of austempered alloyed ductile cast iron are more suitable for gear applications than the classical carburized and hardened steel DIN 34 17220.
https://amme.journals.ekb.eg/article_52051_e3c15fe822ebbe5816474d3b80ad2c58.pdf
1986-05-01
83
97
10.21608/amme.1986.52051
B.
Elsarnagawy
1
Material Department, Military Technical College,Cairo, EGYPT.
AUTHOR
M.
Gaafar
2
Automobile Dept., Military Technical College, Cairo, EGYPT.
AUTHOR
H.
Madi
3
Deputy Chairman, Helwan Iron Foundries, Cairo, EGYPT.
AUTHOR
E.
Makssoud
4
Material Department, Military Technical College,Cairo, EGYPT.
AUTHOR
ORIGINAL_ARTICLE
SCALING CRITERIA OF SOLIDIFICATION AND CASTING PROCESSES
To ensure the quality of large size castinges, production, of casting models on a laboratory scale is necessary as a preliminary step. The main object of this paper is to find, by performing a similarity analysis, the main criterial similarity groups to be preserved in the prototype and a small dimensioned model. The given similarity approach is based on a comprehensive mathematical analysis of the solidification process, heat transfer mechanisms and temperature differentials through the governing differential equations of continuity, momentum and energy. Applying mathematical techniques on these equations, the following dimensionless numbers were found to have a valuable importance : phase change number, superheating number, drift flux number and firiction number. The physical significance of these numbers are discussed and the conditions imposed by them in design of model-casting process are evaluated. The mentioned results are applied to a simple case for the process of casting simulation. Hence, interesting conclusions of the feasibility of this methed for modeling a casting process have been stated.
https://amme.journals.ekb.eg/article_52053_e6e9e6c5173ba378aaf7311e7d5ad5c3.pdf
1986-05-01
99
109
10.21608/amme.1986.52053
SALAMA
MOHAMMED
1
Head of Department of Mechanical Power Engineering and Energy, MTC, Cairo, Egypt.
AUTHOR
ORIGINAL_ARTICLE
THE INFLUENCE OF STAINLESS STEEL SURFACE ROUGHNESS UPON THE FRICTION AND WEAR OF POLYETHYLENE UNDER DRY AND LUBRICATED CONDITIONS
Investigations of the friction and wear of Ultra-high Molecular Weight Polyethylene (UHMWPE) in reciprocating sliding against a range of stainless steel counterfaces of various initial surface roughness, are described in this paper. The tests were carried out either with the wear specimen under dry conditions of contact or lubricated by distilled water. A single sliding speed of 0.097 m/s and two constant loade of 5N and lON were used. The results have shown that there is an optimum scale of surface roughness which yields minimum dry wear rate and coefficient of friction for UHMWPE sliding on EN 58J stainless steel. The tests conducted under water lubricated conditions showed an appreciable reduction in the coefficients of friction and wear rates compared with the values obtained under bry conditions. A mechanism is proposed for the increased wear rate and coefficient of friction on smoother surfaces.
https://amme.journals.ekb.eg/article_52056_42b714f30b43a0b94b309853aaa98040.pdf
1986-05-01
1
10
10.21608/amme.1986.52056
M.
ZAKI
1
Lecturer, Department of Industrial Engineering Production, Faculty of Engineering, Mansoura University, Mansoura (Egypt).
AUTHOR
ORIGINAL_ARTICLE
BENEFICIAL EFFECT OF SHAPING WITH TUBULAR CATHODE IN ELECTROCHEMICAL MACHINING PROCESSES
Although ECM is one of the most widely used machining processes, it is felt. that its capability has not been fully exploited due to difficulties encountered in tooling design. This paper proved the powerfullness of using a tubular cathode as a simple available tool which gives comparatively accurate results. Theoretical analysis based on a modified ECM theory was made for estimating the process variables. Comparison with experimental results yielded a good correlation. Moreover, preliminary tests were carried out for comparison between tubular and single pointed cathodes.
https://amme.journals.ekb.eg/article_52063_0dab60a86899d65148d4d62131544870.pdf
1986-05-01
11
25
10.21608/amme.1986.52063
A.
ABDEL MAHBOUD
1
Assistant professor, Department of Production and Machine Design, Faculty of Engineering & Technology, Menoufia University, Shebin El-Kom, EGYPT.
AUTHOR
ORIGINAL_ARTICLE
THE PREDICTION AND CONTROL OF ECM SURFACES
The application of electrochemical machining for producing components under high degrees of accuracy and surface integrity conditions has increased markedly in an era of rapid and continuous engineering demands. The main attractions of the ECM process are its ability to machine very hard metals and to form complex shapes which are difficult to produce conventionally. The mechanism of surface generation in ECM is somewhat complicated and not quite understood because of the complex nature of the possible reactions occurring during machining in the inter-electrode zone. Incomplete data correlating surface integrity with mechanical properties could hinder the use of the ECM process. The present work highlights the effect of the various inter-related parameters on the surface integrity of electro-chemically machined components with the objective to enable production engineers allocate the suitable working conditions for each specific operation to attain highest degrees of surface quality. The results are finally furnished in the form of empirical relationships with the aim to generalize simple and useful data to be suitable for ECM designers in predicting and controlling surface finishes as required for the intended service of the component.
https://amme.journals.ekb.eg/article_52076_5c19e07dcf462b528d34eb236003e28c.pdf
1986-05-01
27
34
10.21608/amme.1986.52076
S.
EBEID
1
Associate Professor, Faculty of Engineering, Ain Shams University, Egypt.
AUTHOR
A.
ABDEL-MAHBOUD
2
Assistant Professor, Faculty of Engineering and Technology, Menoufia University, Egypt.
AUTHOR
ORIGINAL_ARTICLE
AN ANALYSIS FOR OPTIMAL CHASING CAM DESIGN
The design of chasing cam is necessary due to continuous development of thread cutting.The machine productivity will be determined according the speed of the cam and the number of passes. The cam speed is often limited by the inertia forces. Therefore, it is imperative to choose the cam profile (motion program) with minimum acceleration. This work presents an analysis for various profiles. Six family of curves are deduced,namely; Constant acceleration, Harmonic, Cycloidal, Cubic, Polynomial, and Elliptical. The develpment of numerical controlled machines as well as digital computers requires the combination curve having the optimal value which ensures minimum acceleration. It is hoped that the proposed combination curves can be a useful aid in the field of chasing cam design.
https://amme.journals.ekb.eg/article_52159_cd35d8217a574ca43a516f5abab2bf52.pdf
1986-05-01
35
42
10.21608/amme.1986.52159
S.
ZOROMBA
1
Lecturer of MTD, Production Engineering Department, Suez Canal University, P.O.Box 14 Port_Fouad, Port_Said, Egypt.
AUTHOR
ORIGINAL_ARTICLE
THE PREDICTION OF THE CUTTING EFFICIENCY FOR TURNING OPERATIONS
A series of machining experiments were conducted on steel specimens, and the effect of various machining parameters on cutting forces are presented. Empirical formulae for the estimation of the cutting forces, as functions of the cutting conditions, were deriven. The term "Cutting Efficiency" is introduced, and could be considered as a measure of the performance of the cutting system. An empirical formula for the prediction of the cutting efficiency was established, and it could be used in optimization techniques.
https://amme.journals.ekb.eg/article_52162_66d761c161018dd6f4a3b1cb51cbfd9f.pdf
1986-05-01
43
50
10.21608/amme.1986.52162
Metal cutting
Machining
cutting forces
specific cutting energy
cutting efficiency
M.
Riad
1
Associate Professor, Mechanical Design and Production Department, Cairo University, Egypt.
AUTHOR
A.
Moussa
2
Associate Professor, Production Engineering Department, helwan University, Egypt.
AUTHOR
G.
Badawy
3
Graduate Student, Production Engineering Department, helwan University, Egypt.
AUTHOR
ORIGINAL_ARTICLE
A SEMI-ANALYTICAL METHOD FOR DETERMINING THE SUBSURFACE DAMAGE IN MACHINING
An attempt is made to predict the subsurface damage in the mach-ined components induced in metal cutting using a semi—analytical model based on the identation of a semi-infinite plate with a line load. A model is proposed to calculate the plastically deformed zone underneath the machined surface when cutting with sharp tools. Measured values of tool forces and the tensile yield strength of the material should be used in the analytical model. Experimental measurements were carried out to determine the depth of the plastically deformed layer using a simplified technique. The experimentally measured values agreed well with the depth predicted from the analytical model.
https://amme.journals.ekb.eg/article_52553_eb544031684587e1e5485a370a1bc792.pdf
1986-05-01
51
59
10.21608/amme.1986.52553
M.
Elkhabeery
1
Assistant Professor, Production Engineering & Machine Design Dept., Faculty of Engineering & Technology, Menoufia Univer- sity, Shebin El-Kom, EGYPT.
AUTHOR
ORIGINAL_ARTICLE
SOME ASPECTES ABOUT ED WIRE CUTTING PRODUCT QUALITY
Numerically controlled electro discharge wire cutting process has increasingly been applied in producing various required profiles of hard and heat treated materials. Rowever,there is little published work concerning the effect of ED wire cutting conditions on surface integrity of the machined components. Knowledge of the nature and quality of the surfaces produced under various ED wire cutting consitions is of considerable industrial importance. The objective of this work is to investigate, in a comperhensive manner, the effects of the wire feed rate, wire diameter, pulse duration, and the effectiveacting length on the surface integrity of both high speed and tool steels. The surface region of the machined components is examined using a wide variety of diagnostic techniques. The results of the investigation show that a wide variety of geometrical surface feature!; are generated at varius ED wire cutting conditions. The results also show that a heat affected zone in the surface region is generated that contains variations in hardness and microstructure. The results, in conjunction with those obtained from previous work will lead to a better understanding of the performance of the ED wire cutting and will aid in the production of surface of high integrity.
https://amme.journals.ekb.eg/article_52554_c3175c5b5bb49e8bf663d6d9f81fd793.pdf
1986-05-01
61
70
10.21608/amme.1986.52554
S.
Saleh
1
Cheif of Machining and Prod. Manaq.Department, Military Technical College.
AUTHOR
M.
Elkhabeer
2
Assistant Professor, Production Engineering; Machine Design Department, Faculty of Engineering & Technoloqv, Menofia University, Shebin El-Kom, Egypt.
AUTHOR
M.
Nasser
3
Assistant Professor, Production Engineering; Machine Design Department, Faculty of Engineering & Technoloqv, Menofia University, Shebin El-Kom, Egypt.
AUTHOR
ORIGINAL_ARTICLE
COMPUTERIZED MACHINABILITY DATA BASE SYSTEMS AS APPLIED TO ECM AND EDM PROCESSES
Computerized machinability data base systems are now becoming essential for automating process planning and programming in computer integrated manufacturing sytems. Non-conventional machining plays a significant role in modern high technology engineering processing and contributes to accuracy and component quality. Such processes are extensively used in the jet engine manufacturing and in machining turbine blades and dies. The obective of this work is to present a scientific approach for the application of integrated machining data selection systems to non-conventional machining processes namely, electrochemical (ECM) and electric discharge machining (EDM). The paper presents the choice and use of integrated machining data selection modelling systems with the ultimate goal to help manufacturers, workshop engineers and researchers to achieve optimum cutting conditions. The beneficial advantages of such work include efficient process planning under increased productivity conditions.
https://amme.journals.ekb.eg/article_52555_5d72a98562c9632189ed18a4700068bd.pdf
1986-05-01
1
10
10.21608/amme.1986.52555
S.
EBEID
1
Associate Professor, Department of Design and Production Engineering, Ain Shams University, Cairo, Egypt.
AUTHOR
ORIGINAL_ARTICLE
EXPERIMENTAL INVESTIGATION OF FLOW EQUATION OF SCMC AQUEOUS SOLUTION IN PIPELINES
Frictional pressure loss for flow of Sodium Carboxymethyl Cellulose (SCMC) aqueous solutions in piping system has been experimentally, investigated. Pipes of inner diameters range from 6 to 17.5 mm, were used. SCMC aqueous solutions have been found to behave as pseudoplastic fluids. Smooth and rough pipes have been used for SCMC concentration ranges from 0.03 to 1.1 wt.%. It has been found that the pressure drop-flow rate diagram for pipes was similar to that of Newtonian fluids, with different consistency equation and transient Reynolds number. As concentration increases, the pressure loss increases, apperciably in the laminar region than in the turbulent one.
https://amme.journals.ekb.eg/article_52556_ec31640df68249fc28916eb5602187e9.pdf
1986-05-01
11
19
10.21608/amme.1986.52556
M.
HARIDI
1
Ph.D., Military Technical College, Kobry el Kobba, Cairo.
AUTHOR
M.
HAMZA
2
Eng., Armament Authority, Kobry el Kobba, Cairo.
AUTHOR
Ibrahim
SALEH
3
Ph.D., Military Technical College, Kobry el Kobba, Cairo.
AUTHOR
ORIGINAL_ARTICLE
AUTOMATIC ASSEMBLY - AN ECONOMICAL ANALYSIS
This paper describes a mathematical model for calculating and analyzing the effects of some factors on the economics of the existing automatic assembly systems and those might be developed in the future. Results have been analyzed and compared with each other. Useful conclusions have been obtained and represent that the development of new grippers and feeders have very great benefit to the application of robots in the assembly systems. The conclusions of this work have good agreement with an experimental case study made to assemble a 24-piece gear box.
https://amme.journals.ekb.eg/article_52557_be65062e6bfe278ad2ba96fb8f89f8fa.pdf
1986-05-01
21
30
10.21608/amme.1986.52557
M.
HELALY
1
Lecturer at Prod.Eng. Dept., Alex.Univ., Egypt, and working for Kuwait Institute of Technology.
AUTHOR
ORIGINAL_ARTICLE
THE APPLICATION OF PARETO DISTRIBUTION PRINCIPLE TO QUALITY CONTROL IN REPAIR WORKSHOPS
Pareto principle of maldistribution is based on the fact that in the manufacture or repair of hardware there are almost always a few kinds of defects that loom large both in severity and frequency of occurrence. In either case, these defects are significant because they are costly. The principle states that a relatively few items will account for a disproportionately large amount of total effect. It has been described as a method for distinguishing the significant few from the trivial many.The paper presents a case study where pareto analysis is applied to the defects that are encountered in the machining and assembly processes in an automotive engines major repair workshop. The kinds and distribution of defects are recorded. The vital defects that should take a great deal of consideration if the quality is to be improved, are found out. This enables stressing on quality weaknesses and sheds light on vital problems and rationalizes decisions for solving quality problems.
https://amme.journals.ekb.eg/article_52558_c7f2f71c155126e470a5aa35c1884162.pdf
1986-05-01
31
39
10.21608/amme.1986.52558
Adel
El Shabrawy
1
Ph.D., Egyptian Armed Forces.
AUTHOR
ORIGINAL_ARTICLE
EXPERIMENTAL AND THEORETICAL STUDY ON THE FLAME STABILIZATION BY RECIRCULATION BEHIND A BLUFF-BODY.
An experimental investigation and analytical description have been carried out on the flame stabilization by recirculation behind a bluff-body flame holders. The blowout limits of flames and the length of the recirculation zone have been investigated for cylinderical and spherical bluff-body flame holders. Also, measurements of the influence of the flame holder geometry on the lean blowout limits as well as on the rich blowout limits have been carried out.In the theoretical study, a two-dimensional flow model to describe the mechanism of the flame stabilization by recircul-ation behind a bluff body has been developed. In this model, the process of flame stabilization is governed by the balance between the rates of turbulent mixing and chemical reactions in the shear layer at the recirculation zone boundary. The predicted blowout limits of flames have shown a qualitatively agreement with the observed ones.
https://amme.journals.ekb.eg/article_52559_a8fe8be3a53182b6fda51d7d3a751dbf.pdf
1986-05-01
41
51
10.21608/amme.1986.52559
S.
El-Emam
1
Lecturer, Department of Mechanical Power Engineering, Mansoura University, El-Mansoura, Egypt.
AUTHOR
ORIGINAL_ARTICLE
THEORETICAL REDUCTION OF RATE OF DEPOSITION OF SUSPENSIONS IN TURBULENT FLOW OVER A TILTED FLAT PLATE BY APPLYING AN EXTERNAL ELECTRIC FIELD
Particle deposition from turbulent flow of suspensions on inclined surfaces, is related to many practical problems such as attenuation of solar energy collected by solar flat plate collectors due to dust deposition. In this paper, the effect of external electric field on the deposition of suspensions in turbulent flow over a tilted flat plate is investigated. The external electric field is obtained by a number of equally spaced parallel cylinders having the same voltage and height above the plate. The case of a constant external electric field is also considered. A mathematical model for the flow of suspensions using the combined equation of continuity of fluid and particulate phases with the application of Fick's law and the equations of Poisson, external electric field and rate of deposition along with the proper boundary conditions are given. Numerical solution is obtained using the finite difference method. The effects of the intensity of the external electric field, the number of charged cylinders and their height above the plate on the rate of deposition of the solid particles are studied. The theoretical results indicate that an externally applied electric field obtained by an array of charged cylinders placed parallel to the plate can considerably reduce the rate of particle deposition from turbulent flow of suspensions over a tilted flat plate if the potential on the electrodes of the charged cylinders has an opposite polarity with respect to the polarity of the charge on the particles. In addition, increasing the number of the cylinders for the same applied voltage results in more reduction in rate of deposition. Moreover, for a given applied voltage, there is an optimum height of the array of cylinders that minimizes the total rate of deposition.
https://amme.journals.ekb.eg/article_52560_bf889d173d6d7a1de55320956e03f651.pdf
1986-05-01
1
13
10.21608/amme.1986.52560
S.
ELDIGHIDY
1
Associate professor, Dept. of Mech. Eng., Faculty of Eng., Zagazig Univ., Zagazig, Egypt.
AUTHOR
K.
ALBIDWEIHY
2
Associate professor, Dept. of Elect. Eng., Cairo Univ., Giza, Egypt.
AUTHOR
ORIGINAL_ARTICLE
A RIGIDITY THEOREM FOR SURFACES IN RIEMANNIAN 3-SPACES.
Let M : D→V³ and M→V-³ (D c R²) be two isometric surfaces in the Riemannian spaces V³ and V-³ with curvatures R, R- respectively. We shall prove that the second fundamental forms of the two surfaces are the same provided that: 1- The Gaussian curvature K of M is positive. 2- M and M- have the same second fundamental form on ρ D. 3- For each d ϵ D, Ld :T M(d) (V³)→T M-(d)(V-³ ) is the isometry determined by its restriction Ld to T M (d) (M) which satisfies LdodM = dM-, and Ld {R(x,y) Z} = R-(Ldx, Ldy)Ldz for all tangent vectors x,y,z ϵ T M(d)(M) Also it is shown that the two isometric surfaces M and M- satisfying the above conditions have the same Gaussian and mean curvatures at corresponding points.
https://amme.journals.ekb.eg/article_52561_2f7983b8ea207b774b2d9d68f841e59f.pdf
1986-05-01
15
23
10.21608/amme.1986.52561
RAMY
TALAAT
1
Gen. Dr., Military Technical College, Kobry El-Kobba, Cairo, Egypt.
AUTHOR
ORIGINAL_ARTICLE
ELECTRO-HYDRODYNAMIC ANALOGY SOLUTION OF CONFORMAL MAPPING OF EXTERNAL DOMAIN OF AN AIRPLANE FUSELAGE
Determination of bilinear transformation functions that mutually mapp conformally the exterior of an arbitrarily shaped given contour to exterior of unit circle is of practical importance in several fields of engineering. For solution of this problem, certain numerical techniques are available, suffering from either low accuracy or complicated procedures and long computer time disadvantages.In presented paper is applied an experimental computational technique based on the electro-hydrodynamic analogy.and method of trigonometric interpolation. Required mapping functions are assumed in form of power series with coefficients determined using images of points equally deviding the circle contour.Image points on given contour are determined by electro analogy on electrically conductive paper .The method is applied for conformal mapping of exterior of airplane fuselage sections with and without its horizontal tail surfaces, Mapping series proved to be convergent and fluently changing in harmony with fuselage body streamlining. The method is simple and economic with results of acceptable accuracy. More-over ,it is the only practical solution of conformal mapping problems of real non-idealized actual cross-sectional shapes of modern complicated wing-body combinations. Due to its relation to velocity potential and pressure distributions, longitudinal behaviour of mapping functions with fuselage stations can depict positions of unfavourable pressure gradient and assist its streamlining.
https://amme.journals.ekb.eg/article_52562_be6b1238601d9a3d2ccf94a6237488af.pdf
1986-05-01
25
33
10.21608/amme.1986.52562
O.
ABDELHAMID
1
Department of Aeronautical Engineering , Military Technical College , Cairo , EGYPT.
AUTHOR
ORIGINAL_ARTICLE
A NEW MEASURE FOR THE STABILITY OF HYPERSURFACES IN THE N- DIMENSIONAL EUCLIDEAN SPACE
A new measure of stability on hypersurfaces in En is introduced.
It is the integral
£ (f) = ∫M H1 Hn-2 dσ
where H1 is the ith mean curvature of the hypersurface M. The general conditions for the stability of M under normal deformations are found. The stability on M under II- infinitismal and III-infinitismal deformations and the stability of M under the normal deformations which admit the relationδ II =1/2 (n-1) H1 δ I are also discussed.
https://amme.journals.ekb.eg/article_52565_e5ba282102568fa9c3071b301e9cb604.pdf
1986-05-01
35
44
10.21608/amme.1986.52565
Mohamed
Abd El - Megid
1
Military Technical College, Kobry El - Kobba, Cairo.
AUTHOR
ORIGINAL_ARTICLE
ESTIMATION OF DYNAMIC COEFFICIENTS OF ELLIPTIC HEARINGS WITH VARIED ASPECT AND ELLIPTICITY RATIOS
Computer solution of Reynold's equation applied to an elliptic bearing using numerical methods is employed to obtain the load carrying capacity of an elliptic bearing with horizontal and vertical axes. Numerical integration of pressure results in evaluating fluid-film forces. Numerical differentiation of fluid-film force components determine radial and tangential film stiffness. If the journal runs in equilibrium under some external load, and is displaced incrementally in direction of radial vector of the journal center; numerical solution of Reynold's equation,for each bearing arc, will result in dynamic pressure distribution. Numerical integration of dynamic pressure results in dynamic fluid-film forces. Numerical differentiation of dynamic forces results in tangential and radial damping coefficients. Equations of motion of a journal due to small oscillation of the journal center areused to determine the onset of instability in an elliptic bearing.
https://amme.journals.ekb.eg/article_52566_72d38899c9f9d73c49a310cfc52395e9.pdf
1986-05-01
45
54
10.21608/amme.1986.52566
A.
MOUSTAFA
1
Assoc. Prof. in the dept. of Mechanical Design and Production Faculty of Engineering, Cairo University.
AUTHOR
ORIGINAL_ARTICLE
NUMERICAL COMPUTATIONS OF TURBULENT AND SWIRLING FLOWS IN AXI-SYMMETRICAL COMBUSTOR
Numerical, marching procedure is presented for the calculations of the transport processes in two-dimensional flow characterized by the presence of one coordinate in which physical influences are exerted in only one direction. The differential equations for the transport of mass and momentum with the help of the Prandtle mixing length for turbulence have been solved using the discretization technique. The boundary of the reverse flow zone, which was measured, was introduced to the calculations as an inner boundary. The calculations has been performed for the forward flow passing in the annular space confined by the combustor wall and the reverse flow zone boundary. The boundary of the reverse flow zone was detected accurately, simply and easily by a special flow direction detector probe designed by the author. To verify the calculations, the results were compared with the measured axial and tangential velocities that measured by the Laser Doppler Anemometer. The axial and tangential velocities distributions and the dimensionless stream lines were estimated. The predicted results indicated good agreement with the experimental results.
https://amme.journals.ekb.eg/article_52567_587a1b793b6b611f094a2414972f3bd0.pdf
1986-05-01
55
65
10.21608/amme.1986.52567
Tharwat
FARAG
1
Lecturer, Mechanical Power Department , Faculty of Engineering and Technology-Port Said, Suez Canal University, EGYPT.
AUTHOR
ORIGINAL_ARTICLE
DESIGN OF REDUCED ORDER OBSERVERS FOR GENERALIZED STATE SPACE SYSTEMS CONTAINING UNKNOWN INPUTS
In this paper a method is developed for the design of Luenberger-type observers for linear time-invariant control systems whose state equation is of the form Ex = Ax + Bu + Mg where E is a singular matrix and g is an unknown input vector. The method is based on the singular-value decomposition of the matrix E, and on the reduction of the equation Ex=Ax+Bu+Mg to a system consisting of a differential equation of form W1=F1w1+F2w2 +G1u+K1g and an algebraic equation of the form H1w1+H2w2+G2u+K2g = 0. If w2 can be eliminated from the differential equation by the aid of the algebraic equation and original output equation of the system, the method yields a reduced order observer for the generalized state space system.
https://amme.journals.ekb.eg/article_52570_9f514a008a697a89b1990cfa77c82e17.pdf
1986-05-01
67
78
10.21608/amme.1986.52570
Mohammed
El-Tohami
1
Chairman of Mathematics Department, Military Technical College.
AUTHOR
ORIGINAL_ARTICLE
ON THE STOKESIAN MOTION OF VISCOUS LIQUIDS DUE TO AN OFF-CENTRE SOURCE
The Stokesian motion of viscous liquid lubricants in externally pressurized thrust collar bearings due to an off-centre pressure source has been studied by potential theory. The complex potential function that satisfies the boundary conditions of the bearing has been constructed by reflection across the ring circles. It has been determined in terms of Jacobi Theta Functions. The pressure distribution has been obtained for the following cases:-i- Externally pressurized thrust circular concentric collar bearings.ii- Externally pressurized thrust elliptic collar bearings.
https://amme.journals.ekb.eg/article_52571_687153d10b1b190d8b0adec9a56914cc.pdf
1986-05-01
79
90
10.21608/amme.1986.52571
HELMY
SAFWAT
1
The Professor of Engineering Mechanics, Dept.of Engrg.Math., Faculty of Engineering, University of Alexandria, El-Hadhrah, Alexandria , EGYPT.
AUTHOR
ORIGINAL_ARTICLE
COMPUTER AIDED SHIP DESIGN ECONOMICS
As the computer aided ship design (CASD) is a way to translate the owner requirements into a feasible project through a methodical treatment of ship design problems oftenly by using spirals, the computer aided ship design economics is a way to help the shipowner himself to optimize his requirements by putting the answers of the questions freauently arise to him before putting his order. From the main economical factors which are concerned by the shipowner the design speed, the economical life, and the maximum permissible price of the proposed ship. This paper gives an approach to the optimum predictions of the above-mentioned factors and attempts an analysing procedure for determining the economical particulars for a newly ordered ship. A closed design model (CDM) is developed which-besides the decisions for speed,life,and price-makes the necessary analyses to investigate the sensitivity of these factors to each other and to other technical and economical factors. The algorithm of procedure is explained, flow charts of computer programs are given, and the results of analyses are presented and discussed through the paper.
https://amme.journals.ekb.eg/article_52572_f8f51075e1fdacbd370a20866ab47811.pdf
1986-05-01
1
20
10.21608/amme.1986.52572
G.
YOUNIS
1
Dr., Lecturer , Faculty of Engineering ,Suez Canal University Dept. of Ship Engineering , Port Said , EGYPT .
AUTHOR
ORIGINAL_ARTICLE
PERSONAL COMPUTERS IN TEACHING DYNAMICS AND MECHANISM ANIMATION
https://amme.journals.ekb.eg/article_52573_0779b5b700dc5fc2a85c88e0af9d607e.pdf
1986-05-01
21
30
10.21608/amme.1986.52573
ALI
ABOU EZZ.
1
ENG., Dept. Mechanical Engineering KING ABDUL AZIZ UNIVERSITY P.0 Box 9027, Jeddah 21413 Saudi Arabia.
AUTHOR
ORIGINAL_ARTICLE
THE INTEGRATION OF INDUSTRIAL ROBOTS INTO CIM SYSTEMS
Today we are seeing the beginning of Computer Integrated Manufacturing (CIM). However, we have yet to transform these concepts into practice engineering disciplines. The role of the robot in CIM is also new, and we are beginning to see robot manufactures and capabilities which will meet the challenges of CIM.The robot is a major component of CIM technology. It appears to be the nucluous around which the technology is forming. Hence, the objective of this paper is to investigate the importance of the integration of industrial robots (IR) into CIM, thus clarifying one of the most important key technolo-gies of the high level automated production within the Factory of the Future (FOF).
https://amme.journals.ekb.eg/article_52574_d94b4c3804bd64c509bebf63d6b5e19a.pdf
1986-05-01
31
39
10.21608/amme.1986.52574
M.
ABDIN
1
Assist. Prof., Faculty of Eng., Ain Shams Univ., Design and Production Eng. Dept., Cairo, Egypt.+
AUTHOR
ORIGINAL_ARTICLE
COMPUTERISED CALCULATIONS OF AUTOMOBILE CLUTCH ASSEMBLY
The calculation process of automobile friction disc clutch assembly has been aided via the creation of a special computer program . Input data to the program is different parameters of the vehicle and road . The program will determine the design dimensions according to materials used for the clutch assembly parts and design parameters values. It will perform all required calculations , checkings and modifications required for the complete design regarding the friction plate,pressure plate,clutch springs and clutch shaft. Sutch a program beside helping the designer in his main job,it gives him also the possibility to study the influence of some design parameters on the assembly performance. As an example for the study of changing design parameters on the performance,a special routine is written to give the effect of changing the thickness of pressure plate on the increase of its temperature during the clutch slip . another routine is written to study the effect of road inclination angle on the clutch temperatur rise. The presented p-ogram was applied to make the calculations and analysis of the Jeep car (GAZ-69) as a real example of applications.
https://amme.journals.ekb.eg/article_52575_f281ce7954413f31cc4133d15a01840b.pdf
1986-05-01
41
55
10.21608/amme.1986.52575
SAID
HASSAN
1
Col.Dr., Lecturer at the department of Motor Vehicles , Military Technical College , Cairo , EGYPT.
AUTHOR