Spur Gear

One of the most important design parameters in extrusion process is the shape of die profile. In the present research work, an optimum extrusion die profile has been obtained through implementation of slab analysis in a computational algorithm. Moreover, extrusion process through both optimum conical and curved die has been performed experimentally and also by finite element method. It has been demonstrated that material work hardening characteristics and friction condition have remarkable effects on the optimum streamlined die profile. Also, results prove that the streamlined die profile designed based on the developed approach, is superior to the conventional conical dies from both metallurgical and manufacturing perspectives. Consequently, the proposed method can be regarded as an efficient and reliable tool for designing streamlined die profiles. Hence, this technique can be used to produce desirable conditions in both process and product quality in terms of extrusion force, deformation homogeneity and die wear.

Manufacturing technologies of micro parts were studied in nano grained alloy. During compressive test at 300 , the Al alloy showed stain softening phenomenon by grain boundary slid ℃ ing regardless of strain rate. Micro spur gear with ten teeth (height of 200 µm and pitch of 250 µm) was fabricated with sound shape by micro forging. During micro forging, increase of applied stress induced by friction between material and die surface was effectively compensated by decrease of stress by strain softening behavior and as a result, flow stress increased only about 50 MPa more than that in compressive test

In present work, manufacturing technologies of micro parts by micro forging and pressing were studied using strain softening phenomenon in nano grained Al-1.5mass%Mg alloy. During compressive test at 300, the Al alloy showed stain softening phenomenon by grain boundary sliding regardless of strain rate. Micro spur gear with ten teeth (height of 200 μm and pitch of 250 μm) was fabricated with sound shape by micro forging. During micro forging, increase of applied stress induced by friction between material and die surface was effectively compensated by decrease of stress by strain softening behavior and as a result, flow stress increased only about 50 MPa more than that in compressive test. However, in micro pressing, flow of material did not occurred sufficiently to fill die and the resultant shape of gear was very poor.

Experimental results on mechanical efficiency and durability of spur gears are presented. Reducing the power losses and increasing the reliability of gears are fundamnetal aspects of the design of transmissions. In order to analyze the tribological performance of innovative coatings and laser texturing, three different types of spur gears were tested: standard carburized gears, WC/C-coated carburized gears, and carburized gears with laser texture pattern. Tests have been carried out through a power recirculating test rig equipped with a single-stage transmission; power losses were evaluated by analyzing the torque-meters signals; several pictures of the teeth were taken at scheduled times to monitor the wear progression. In conclusion, results are presented and discussed.

Gears are one of the most basic components of any machine or mechanism. Spur gear is the most common means of transmitting power in the modern mechanical engineering world. The main objective of this research paper is to analyze the bending stresses occur on the gear tooth profile when subjected to loading condition with the help of FEM and Photo-elastic technique. Photo elastic stress analysis is a technique that provides stress distribution over an entire object/structural member of interest it is based on the property of some transparent material to exhibit colorful pattern when viewed with polarized light. These patterns occur as the result of alternation of the polarized light by the internal stresses into two waves travel at different velocities. In this work root radius are taken gear parameters, how stress redistribution are taken place by varying this parameter studied. The stresses are calculated with the help of the FEA this result are compared with the stresses calculate...

Gears are one of the most basic components of any machine or mechanism since few centuries. Gears have wide variety of applications but they are commonly used for transmission systems. Gearing is the most critical component in a mechanical power transmission system and industrial machineries. As there are so many merits of the gears, it also has some limitations i.e. weight & Size. The weight of gear makes it difficult to use gears for compact and light duty applications. In this study some geometrical features have been incorporated in the spur gear to optimize the weight and to know its effect on the development of stresses. A finite element model of spur gear is considered for the study and static stress analysis is carried out using ANSYS 14.5.

of involute spur gear pair is carried out using finite element analysis tool ANSYS14.5. Gear noise and vibration is a major problem in many power transmission applications this problem becomes more significant in applications with higher operating speeds, where there is vibratory excitation which is related to the gear transmission error. The goal of modal analysis in this research paper is to determine the natural mode shapes and frequencies of the present spur gear pair and to comparatively analyze with frequencies of the geometrically modified involute spur gear pair during free vibration as well as in pre-stress condition.

Gears have wide variety of application. Their application varies from watches to very large mechanical units like the lifting devices and automotives. Gear generally fails when the working stress exceeds the maximum permissible stress. The main objective of this paper is to analyze the bending stresses occur on the gear tooth profile of gear used in gear box of special purpose machine also effect on bending stress by variation of the gear parameters. Face width and root radius are taken gear parameters, how stress redistribution are taken place by varying this parameter studied. The stresses are calculated with the help of the FEA this result are compared with the stresses calculated by Lewis equation. For this work parametric modeling is done using Pro-e WF 5.0 and for analysis ANSYS 12.0 workbench is used. This work helpful to conclude effect of bending stress on gear tooth profile by variation of gear parameters also give the comparison of FEM method with analytical calculation.

Titreşim analizi, makine elemanları ve yapılarda oluşan arızalar hakkında bilgi edinmede yaygın bir şekilde kullanılan erken uyarıcı metotlarının başında gelmektedir. Bu yöntemde, titreşim analiz sonuçları sinyal işleme, yapay zeka, istatistiksel analiz yöntemleriyle işlenerek dişli hata tespiti yapılabilmektedir. Bu çalışmada amaç, düz dişlilerdeki aşınma hatasının sebep olduğu titreşimlerdeki değişimlerin istatistiksel proses kontrol grafiklerinde analiz edilerek aşınmanın varlığını tespit etmektir. Dişli test düzeneğinde incelenmek üzere, düz dişli yüzeylerinde suni olarak aşındırma işlemi uygulanmış ve sonra bu dişliler takılıp sistem çeşitli ön yük ve devir şartlarında çalıştırılarak titreşim verileri kaydedilmiştir. Sağlam dişli ile aşınmış dişli verileri istatistiksel proses kontrol grafiklerinde analiz edilerek hatanın tespiti gerçek zamanlı deneysel çalışma ile grafiksel olarak gösterilebilmiştir. Vibration analysis is one of the early warning methods widely used in obtaining information about faults occurring on the machine elements and structures. In this method, gear fault detection can be performed by analyzing of the vibration test results using signal processing, artificial intelligence and statistical analysis methods. The objective of this study is detection the existence of wear by examining changes in the vibrations of spur gears due to wear faults in statistical process control carts. In this study, artificial wear was created on the surfaces of spur gears in order to be examined in gears test rig. Then, these gears were attached and vibrations data were recorded by operating the system at various loading and number of cycles conditions. Detection of fault was demonstrated by analyzing undeformed and worn gears data in statistical process control carts by means of realtime experimental studies. Anahtar kelimeler: Düz dişli çarklar, Dişli arızaları, Arıza tespiti, İstatistiksel proses kontrol.

In the standardized method ISO 6336, the load distribution of spur gear stages is taken into account by the face load factors KHβ and KFβ. Both face load factors depend on the maximum load per unit face width and the average load per unit face width in the mesh. Regarding more sophisticated local calculation methods, precise information about the load distribution in the tooth contact gets more and more important. The load distribution of spur gear stages depends on a variety of parameters. Main influence factors are gear geometry (such as geometrical parameters, manufacturing accuracy, running-in effects and flank modifications) as well as elastic deformation and deviation (by housing, shafts, bearings, bearing clearances, wheel bodies, teeth, Hertzian contact). The calculation of the load distribution of gear stages requires a detailed analysis of the deformation behavior of the system gear-shaft-bearing-housing. There are several computer programs to calculate load distribution in the tooth contact of cylindrical gear stages. Some of these programs use analytical approaches (Load Distribution Program -Ohio State University (Harianto, J., 2006); LVR -Technical University of Dresden ; RIKOR -Technical University of Munich (Neubauer, B. and Weinberger, U., 2016)), others use FEM approaches (STIRAK -RWTH Aachen (Ingeli, J., 2014)). The advantage of these specialized programs in comparison to a full FEM approach is the efficient parameterization of gears and the very short calculation time while delivering high precision results. Measuring the load distribution in tooth contact is difficult. Contact patterns contain no information about the amount of load acting in contact. Using strain gauge sensors to measure the load distribution in tooth contact are state of the art (Arai, N. and Harada,

Gear mesh stiffness (GMS) is a principal factor in understanding a dynamic behavior and estimating a health condition of the gear system. Lots of methodologies have been proposed to estimate GMS in normal and abnormal states. However, most of them are performed in an analytical way, therefore experimental studies are limited. Moreover, previous experimental studies have limitations that they were only performed either in a static state or for a normal gear. In this study, we develop a methodology to estimate GMS of a rotating gear in faulty states, root crack and spalling. In the procedures, we employ transmission error (TE) which is defined as the difference between rotation of input and output gear. The methodology proposes the concepts of relative stiffness to remove the effect of low frequency component from shaft motion and variability of individual teeth, and corrected stiffness to exactly estimate GMS of cracked gear. Meanwhile, the study proposes a differentiating algorithm of gear faults between root crack and spalling considering the failure mechanisms of each fault. The developed algorithm is validated measuring the TE from a test-bed of a spur gear. Consequently, the algorithm has differentiated the gear in root crack and surface failure, and estimated the GMS of the gear in faulty states.

Both passive and active shock isolation systems haye been previously investigated. HoweveT, passivc systems are limited in that they cannot adapt to different load condi- tLons; aetlve systems are not practical in many appLicatlons. as the)' may reguire large power supplies. Another solution to the prob[em is te implement a "smart'damp- ing system, which typica[ly requires little power. is con- trollable in real-time. and achieves nearly the sarne performance as an active system. This paper focuses on shock lsolatien using these "srnarf' darnping devices, Fol- lowing the basic problem tbrmulation, the optimal design ef passlve and active shock isotators is given. These re- sults are then extended to the "smart" (.semi-active') b'hock isolatien case. Theoretiea[ aiialysi$ sho"'s that ifthe iinear spring stlllhess is properly chosen and the contro"'orce is appropriatcly regulated. the shock isolator using "smart" damping ean achieve optimal perforrnance and has a better robustness than the passive shock isolator. The cencept of shock isolation is frequently encountered. For exampte, driving vehicle on a bumpy road causes shock N,'ibration which matr severely impair vehicle handling performance; paradropping deliveries in a mititary expeditionarv' logistics environment introduces unfavorable impact disturbances to the sensitivc equipment packed inside at the time of landing. The impact loads arc frequently quite 1arge when compared with the [owor moderate-leve] disturbances encountered during norma] operating conditions; consequcntly.

Gear transmission systems are very important machine elements and their failure can lead to losses or damage of other mechanical components that comprise a machine or device. Since gears are applied in numerous mechanical devices, there is need to design and subsequently optimize them for intended use. In the present work, two objectives, viz., volume and center distance, are minimized for a rotary tiller to achieve a compact design. Two methods were applied: (1) analytical method, (2) a concatenation of the bounded objective function method and teaching-learning-based optimization techniques, thereby improving the result by 44% for the former and 55% for the latter. Using a geometric model and previous literature, the optimal results obtained were validated with 0.01 variation. The influence of design variables on the objective functions was also evaluated using variation studies reflecting on a ranking according to objective. Bending stress variation of 12.4% was less than contact stress at 51% for a defined stress range.

The modelling and optimization of gear systems is a complex procedure with results dependent on the conceptual formulation of the problem, uncertainty, bias and imprecision in weight assignment. Furthermore, tacit information is often omitted in design processes. In this study, a gear concept selection procedure considering "voice of customer" VOC and tacit statements is discussed while extending a gear selection matrix introduced by N. Marjanovic In the current research, two case studies are investigated while considering tacit knowledge. To demonstrate this concept, fuzzy logic is applied to interpret linguistic evaluations by both customer and design teams in the (QFD) Quality Function Deployment and to select alternatives using the Fuzzy-AHP method. The obtained results reflect the impact of tacit knowledge on gear selection methods.

Gear system optimization is currently topical amongst researchers. To this end, problem formulation is key and therefore knowledge of parameter influence and variation behaviour is indispensable. In this research work, four gear volume models were investigated for volume minimization while considering six variables viz. face width, module, pinion tooth, hardness, and pinion and gear shaft diameters. Three algorithms viz. teaching learning-based optimization (TLBO), particle swarm optimization (PSO) and firefly algorithm (FA) are employed to obtain the optimal volume and design parameter variation study. The convergence rate of each algorithm for each gear model is contrasted against other algorithms applied in the study. Experimental runs have also been conducted to determine standard deviation and mean values. Variation studies on the volume objective reflect relevant observations noted for parameter setting and optimization. The results obtained can assist the designer in setting ...

As a service to authors and researchers we publish this version of the accepted manuscript (AM) as soon as possible after acceptance. Copyediting, typesetting, and review of the resulting proof will be undertaken on this manuscript before final publication of the Version of Record (VoR). Please note that during production and prepress, errors may be discovered which could affect the content.

Gear transmission systems are very important machine elements and their failure can lead to losses or damage of other mechanical components that comprise a machine or device. Since gears are applied in numerous mechanical devices, there is need to design and subsequently optimize them for intended use. In the present work, two objectives, viz., volume and center distance, are minimized for a rotary tiller to achieve a compact design. Two methods were applied: (1) analytical method, (2) a concatenation of the bounded objective function method and teaching–learning-based optimization techniques, thereby improving the result by 44% for the former and 55% for the latter. Using a geometric model and previous literature, the optimal results obtained were validated with 0.01 variation. The influence of design variables on the objective functions was also evaluated using variation studies reflecting on a ranking according to objective. Bending stress variation of 12.4% was less than contact...

Les systèmes de transmission de puissance par engrenages sont largement utilisés dans de nombreuses applications industrielles grâce à leur performance. Cependant, ces systèmes sont souvent sujet de différents types de défauts, tels que les défauts d'excentricité, de fissure et d’écaillage d’une ou plusieurs dents. Ces défauts modifient directement leurs comportements dynamiques. Ces modifications se traduisent physiquement par des vibrations excessives, qui introduisent des bruits de fonctionnement et d’instabilités du système. Ces phénomènes ont un impact néfaste sur la performance des engrenages et leur durée de vie. La modélisation de ces systèmes, de leurs endommagements et des modes d’apparition et de propagations s’avère profitable pour assurer leur fiabilité. 
Ce travail s’inscrit dans cette problématique en proposant, d’une part, un modèle mathématique qui décrit le comportement dynamique des engrenages dans les conditions de fonctionnement avec et sans défaut d’excentricité. Et d’autre part, une méthode d’analyse de la réponse vibratoire dans le domaine temporel pour la détection de ce type de défaut et de sa sévérité. Le modèle développé prend en compte les paramètres géométriques et dynamiques de l’ensemble de la structure réducteur de vitesse à deux étages. La détection est réalisée par extraction des indicateurs de surveillance sur la réponse dynamique du système. Enfin, pour analyser l’influence de la sévérité du défaut sur la sensibilité des indicateurs de surveillance, différents niveaux de défaut d’excentricité ont été simulés. Les résultats obtenus montrent que le Kurtosis et le Facteur de Crête sont les deux indicateurs permettant de détecter la présence d’un défaut d’excentricité et sa sévérité.
Mots clés : Engrenage, Excentricité, Modélisation, Détection, Kurtosis, Facteur de crête.

This paper presents a study on the influence on the quasi-static transmission error of symmetric long profile modifications on high contact ratio spur gears. A previously developed model for the load sharing ratio and quasi-static transmission error, based on the hypothesis of equal delay interval in all the teeth in simultaneous contact, has been used. The simple formulation of the model allows to obtain the equation of the required profile modification to ensure a preestablished function of load sharing ratio or quasi-static transmission error. From this model, the tip reliefs for minimum peak-to-peak amplitude of quasi-static transmission error and for minimum dynamic load, have been obtained. In both cases, the optimum length of modification has been expressed as a function of the contact ratio.

A comparison among different approaches of the meshing stiffness of spur gears has been carried out. The influence of each one on the load sharing, and subsequently on the determinant tooth-root and contact stresses, has also been studied. Equations for the evolution of the meshing stiffness along the path of contact according to all these formulations are also provided.

A comparison among different approaches of the meshing stiffness of spur gears has been carried out. The influence of each one on the load sharing, and subsequently on the determinant tooth-root and contact stresses, has also been studied. Equations for the evolution of the meshing stiffness along the path of contact according to all these formulations are also provided.

This paper presents a study on the influence on the quasi-static transmission error of symmetric long profile modifications on high contact ratio spur gears. A previously developed model for the load sharing ratio and quasi-static transmission error, based on the hypothesis of equal delay interval in all the teeth in simultaneous contact, has been used. The simple formulation of the model allows to obtain the equation of the required profile modification to ensure a preestablished function of load sharing ratio or quasi-static transmission error. From this model, the tip reliefs for minimum peak-to-peak amplitude of quasi-static transmission error and for minimum dynamic load, have been obtained. In both cases, the optimum length of modification has been expressed as a function of the contact ratio.

Whilst vibration, noise and acoustic emission analysis for gear fault diagnosis/prognostic are well established, however, the application of wear debris morphological analysis to diagnosis and prognostic health management field is still in its infancy stage. This paper describes an experimental investigation on a pair of spur gear in which “induced” wear modes were allowed to occur, namely, moisture corrosion, acid-attacked corrosion, hard contaminant related wear. It can be concluded from preliminary results presented in this particular paper that wear debris characteristics exhibited a direct relationship with different wear modes, thus, it should be possible to detect, diagnose and/or prognoses gear wear utilization of wear debris morphological analysis.

In this paper the sliding velocities of plastic non-conventional spur gears is analysed. There are two peculiarities to be taken into account when metal gear practice is applied: the variable tooth height along the gear face width and the special meshing conditions of plastic gears. The study is based on the curved face width spur gear solid modelling which enable gear tooth geometry to be produced. A primary analysis shows the effect of the suggested spur gear design on the sliding velocity. Different curvatures and heights of the non-standard gear teeth show the influence of the tooth geometry on sliding velocity variation, a particular criteria for a further study on the optimisation of the gear geometry.

In this paper, an experimental study was conducted on a gear mechanism with eccentricity anomalies, emphasising advanced time-frequency domain methods to improve the diagnosis. Vibrations captured under various operating conditions were examined using RPM-frequency mapping, Short-Time Fourier transform (STFT), 3D waterfall FFT, and 3D Time-Frequency analysis. These techniques allowed for more accurate detection of eccentricity signs, including its impact on the interaction between gears and transmission performance. The results showed that elaborate phenomena such as intense modulation and nonlinear behaviors complicate accurate fault detection using traditional methods based solely on time and frequency domain. However, the multidimensional method adopted here allows for highlighting localised signal indicators that are directly associated with transmission disturbances due to eccentricity. This work, therefore, highlights the need to apply time-frequency methods to monitor the condition of gears and optimize their maintenance more effectively.

This paper employs a nine-degree-of-freedom dynamic model, considering torsional and lateral motions, to analyse the dynamic characteristics of a two-stage spur gear system. The model incorporates gear eccentricity faults and dynamic transmission errors by establishing a mesh stiffness model. The differential vibration equations for the spur gear system are derived using the Lagrangian method. Numerical simulations are conducted using a combination of the Short-Term Fourier Transform (STFT), 3D Waterfall FFT (Fast Fourier Transform), and RPM-frequency mapping technique under various operating scenarios. Analysing the responses imposed by the system under both regular and chaotic vibrations reveals that gear eccentricity faults significantly impact the system's performance. The frequency content changes over time and 3D plots provide a more detailed frequency-RPM representation, allowing the detection of transient faults in gears compared to the time domain and frequency domain. Theoretical analysis confirms the effectiveness of the STFT and 3D Waterfall FFT-based frequency-RPM transmission error detection approach.

The design procedure, load capacity, mathematical model, analysis of worm and worm gear for plug valve has not been investigated, which is a great barrier for the users. This research focuses on addressing these issues by design of gear, developing mathematical model, dynamic analysis of gear and experimental study to find out efficiency of worm gear for plug valve application.

Purpose: This paper propose a method to optimise the module of cutting conical spur gear, after being worn or broken, with the aid of Computer-Aided Design (CAD). The suggested method allows determining the geometric features of a pair of conical spur gear after worn. Design/methodology/approach: The approach consists of drawing real tooth model, with dimensioning characteristics by CAD; extracting a database of tooth drawing that permits the determination of the real volume by mass destruction. It also allows creating a virtual model, by theoretical geometric characteristics, to calculate the volume. Findings: This approach allows giving an approximation of the conditions of the machine function. However, the optimisation of the module is only a link one chain, for other parameter influences on the good working of pairs; we could mention the condition of assembly and the tribological aspects. Practical implications: A simulation package, R2000, was used and an "AutoCAD" s...

The magnitude and location of stress intensity factor (SIF) in mode I (K I ), mode II (K II ), mode III (K III ) relies mainly on the geometry and location of the crack tip, variation in magnitude of load due to multiple pair contact along the active profile and the distribution of the load along the face width of a spur gear drive. Mostly, in literature the calculation of SIF in gear were carried out either by using a two dimensional (2D) Finite element model (FEM) with point load for unit width or a three dimensional (3D) FEM with uniform / parabolic load distribution along the face width without considering load sharing effect between the multiple pairs in contact. In the present study, an attempt has been made to explore the significance of the load distribution along the face width and the load sharing between the pairs when the contact moves from the highest point of tooth contact (HPTC) to the lowest point of tooth contact (LPTC) on the SIF calculation. A comparative study has been made by using a validated 3D single tooth spur gear FEM with four different load cases such as case 1: Uniform load distribution along face width without considering load sharing between the pairs, case 2: Uniform load distribution along face width by including the effect of load sharing between the pairs, case 3: Actual load distribution along the face width without considering load sharing between the pairs, case 4: Actual load distribution along the face width by including the effect of load sharing between the pairs. The stiffness based approach was used to calculate the load distribution ratio (LDR) of a contact point along the contact line and the load sharing ratio (LSR) between the pairs in contact. The detailed analysis showed that case 1, case 2 and case 3 load cases overestimate the SIFs comparing to the case 4. The first three load cases overestimate the K I by 39%, 2.5%, and 45% and K II by 390%, 36%, and 129% and K III by 282%, 47%, and 132% respectively when compared to load case 4. The results of this study provide valuable guidelines for the crack propagation as well as life prediction calculations for spur gear drives.

This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Gears are power transmission devices in between input and output of machines, these power transmitting elements are very compact, and they transfer power with minimum loss. Due to the nature of their different speed ratios they are used for different applications like high speed marine engines, automobiles etc. Different materials are used for preparation or fabrication of gears like metals (steel or brass), plastics (nylon or polycarbonate). In this project spur gear is designed by CAD software and fabricated by using 3D printer, for 3D printing materials require like plastics or ceramics but for this project plastic material is used that is polylactic acid (PLA). By using 3D printer spur gear is produced within a small period with better dimensional accuracy than conventional method like milling etc.

Noise and vibration problems associated with complex mechanical structures can be well addressed as a priority, so that appropriate treatment of such structure has taken place in this work. In the present work, the use of viscoelastic materials has proposed as a strategy intended for passive vibration control. For vibrating structures, damping treatment is attempted for investigating the effect of damping on structural response with the help of simulations using CAE software. This analysis helped us to achieve the prediction of the dynamic behavior of complex structural systems featuring viscoelastic damping with the assistance of sophisticated prediction tools, followed by validation of actually preforming Numerical analysis on fabricated structure. The dependence of stiffness and damping properties on frequency and temperature has examined. Modal and Harmonic analysis techniques is employed for simulating the response of viscoelastic structures using finite element method. Finally...

In this paper, on the basis of the bending produced by the normal force which is applied in contact point of teeth flanks, the contact force of external spur gearing was determined. For the calculus methodology presented in this paper, a computer program has been developed.

In this paper, on the basis of the bending produced by the normal force which is applied in contact point of teeth flanks, the contact force of external spur gearing was determined. For the calculus methodology presented in this paper, a computer program has been developed.

Experimental results on mechanical efficiency and durability of spur gears are presented. Reducing the power losses and increasing the reliability of gears are fundamnetal aspects of the design of transmissions. In order to analyze the tribological performance of innovative coatings and laser texturing, three different types of spur gears were tested: standard carburized gears, WC/C-coated carburized gears, and carburized gears with laser texture pattern. Tests have been carried out through a power recirculating test rig equipped with a single-stage transmission; power losses were evaluated by analyzing the torque-meters signals; several pictures of the teeth were taken at scheduled times to monitor the wear progression. In conclusion, results are presented and discussed.

This paper describes an experimental investigation on a pair of spur gears in which wear and pitting were intentionally allowed to occur, namely, moisture corrosion pitting, acid-induced corrosion pitting, hard contaminant-related pitting and mechanical induced wear. A back to back spur gear test rig was used throughout 32 test series. The tests samples of wear debris were collected and assessed through the utilization of an optical microscope in order to correlate and compare the debris morphology to pitting and wear degradation of the worn gears. In addition, weight loss from all test gear pairs were assessed with utilization of statistical design. It was observed that there were significant distinctions between both weight losses, wear debris morphology generated from each induced pitting conditions and worn surface characteristics. It can be deduced that wear debris characteristics exhibited a direct relationship with different pitting and wear modes. Thus, it should be possible to detect and diagnose gear pitting and wear utilization of worn surfaces, generated wear debris and quantitative measurement such as weight loss.

In gearboxes, vibration stemming from load fluctuations and gear defects poses significant challenges. However, accessing and mounting vibration transducers in gearboxes can often be difficult. To address this, an experimental approach utilizing FFT analysis is employed to detect various types of gear tooth faults. By analysing vibration patterns, fluctuations in gear load gear faults can be identified effectively. This involves comparing signals from healthy and defective conditions using FFT analysis to trace sidebands of high-frequency vibrations. Validation is achieved by inputting data from an Accelerometer into LabVIEW, This comprehensive approach serves as a valuable tool for monitoring gear health under various operating conditions.

Injection forging is a nett-shape manufacturing process which enables the forming of complex component-forms that are difficult to form by conventional metal-conversion processes. The state-of-the-art of the research in this subject is reviewed with reference to different process configurations, forming limits, energy/pressure requirements, process modelling and product forms.

In this study, root stresses of spur gear tooth are analysed as plane stress problem by the finite element method (FEM). The effects of rim thickness of spur gear on the root stresses is investigated. The computer program which produces a profile of the gear tooth for obtaining mesh region presenting the problem is prepared. In order to examine the effect of the rim thickness on the root stresses, the stress analysis is made on single tooth models varying the rim thickness in steps. On the basis of these investigations a suitable rim thickness of gear model for stress analysis by FEM is proposed.

The theoretical basis and performance characteristics of helical gear design, this work is to conduct a comparative study on helical gear design and finite aliment as well as analytical approaches finite element approach in ANSYS one of the most critical in mechanical power transmission system the gear are generally used to transmit power or torque and the efficiency of transmission is very high when compared to other kind of transmissions.

This paper presents an approach to calculate the parameters of a family of noncircular gears. The calculations of the general elliptical rolling curves are based on complex algebraic methods. Two methods was developed to calculate the contour curves of involute profile. The first based on the virtual manufacturing in a CAD system, while the second by determines the contour curves analytically. These gears were manufactured by wire EDM technology.

Lubrication and vibration are crucial to the reliability and efficiency of gear device, especially in high-speed, heavy-load condition. In this study, a novel model based on tribo-dynamic theory is introduced to investigate the lubricating and dynamic performances of high-speed spur gear. In conjunction with a finite element model, the time-varying meshing stiffness and static transmission error are derived precisely in the form of Fourier series. An efficient iterative algorithm, integrated Newmark method with multigrid method, is developed for solving the governing equations. The simulation results indicate that it is necessary to utilize tribo-dynamic model to assist lubrication design and vibration control of spur gear in high-speed condition.

Lubrication and vibration are crucial to the reliability and efficiency of gear device, especially in high-speed, heavy-load condition. In this study, a novel model based on tribo-dynamic theory is introduced to investigate the lubricating and dynamic performances of high-speed spur gear. In conjunction with a finite element model, the time-varying meshing stiffness and static transmission error are derived precisely in the form of Fourier series. An efficient iterative algorithm, integrated Newmark method with multigrid method, is developed for solving the governing equations. The simulation results indicate that it is necessary to utilize tribo-dynamic model to assist lubrication design and vibration control of spur gear in high-speed condition.

In recent times, the gear design has become a highly complicated and comprehensive subject. A designer of modern gear drive system must have to remember that the main objective of gear drive is to transmit higher power with comparatively smaller overall dimensions of the driving system which can be constructed with minimum possible manufacturing cost, runs reasonably free of noise and vibration and which requires little maintenance. In this paper single stage spur gear train and helical gear train with a idler gear are designed by American Gear Manufacturing Association (AGMA) standard. A idler gear is placed between two gearwheel to obtained the same direction of rotation. AGMA stress equation is used to determined the tooth bending strength and surface contact strength. As a result, dimensions of gears are find out and comparative study is carried out to select the optimum design of gear train for a given input parameter

In recent times, the gear design has become a highly complicated and comprehensive subject. A designer of modern gear drive system must have to remember that the main objective of gear drive is to transmit higher power with comparatively smaller overall dimensions of the driving system which can be constructed with minimum possible manufacturing cost, runs reasonably free of noise and vibration and which requires little maintenance. In this paper single stage spur gear train and helical gear train with a idler gear are designed by American Gear Manufacturing Association (AGMA) standard. A idler gear is placed between two gearwheel to obtained the same direction of rotation. AGMA stress equation is used to determined the tooth bending strength and surface contact strength. As a result, dimensions of gears are find out and comparative study is carried out to select the optimum design of gear train for a given input parameter

Reverse Engineering (RE) is a technique that uses different approaches to obtain characteristic data of a physical object for which no drawings, documentations or computer models are available. This paper presents an experimental approach of reverse engineering for reconstructing the spur gears. 3D CAD model is made using digital image processing (DIP). Gears have been scanned using a single digital camera. The digitized data of spur gears was collected and processed using MATLAB package with Digital image processing (DIP) technique. It is worth mentioning that the accuracy of the modeling process of given piece depends on the number of points that are captured on the work piece surface. This proposed method is the best tool used in reverse engineering because it is faster and more accurate than the method used the coordinate measurement machines (CMMs). To confirm the effectiveness of the proposed method a comparison is made using image processing between the first data of spur gea...

The purpose of this research was to select the optimal materials for various spur gear designs. Three gears were designed using three variables: the number of teeth, the material weight constant, and the Lewis factor form. The particularly recommended for the design of spur gears.

Vibration analysis is widely used in machinery diagnostics and the wavelet transform has also been implemented in many applications in the condition monitoring of machinery.Incontrast to previous applications, this paper examines whether acoustic signal can be used effectively along vibration signal to detect the various local faults in gearboxes using the wavelet transform. Four commonly encountered local faults, tooth wear, tooth crack, broken tooth and insufficient lubrication of the gear tooth breakage and tooth crack, were simulated. The results from acoustic signals were compared with vibration signals. The results suggest that acoustic signals are very affective for the early detection of faults and may provide a powerful tool to indicate the various types of progressing faults in gearboxes.

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.