Gearbox Housing Research Articles

Investigation of the heavy duty truck gear drive failure

For heavy vehicle systems, within the power transmission chain from the driving machine to the working components (wheels), gears have a large share of application in the form of gearboxes, differentials and speed reducers. Their purpose is to achieve the highest possible output torque at the working components. In one heavy-duty truck, the gearbox lost its working capacity due to the failure of its vital parts: a tapered roller bearing and a helical gear. The analysis presented in this paper, conducted on the basis of experimental and analytical methods, showed that, due to inadequate installation of the bearings’ outer ring in the gearbox housing in one intermediate shaft support, the roller bearing performed its elementary function in very unfavorable working conditions of mechanical and thermal nature. Due to the damage accumulation, the roller bearing gradually lost its working capacity. As a result, the intensity of the working conditions of the entire gearbox increased. At the moment when they reached the critical value from the aspect of the gear teeth bending strength, volumetric destruction occurred, i.e fracture of the helical gear tooth, and thus the cessation of gearbox power transmission.

Gear fault diagnosis using gear meshing stiffness identified by gearbox housing vibration signals

Gear fault diagnosis using gear meshing stiffness identified by gearbox housing vibration signals

МЕТОД РАСЧЕТА УСТАНОВОК ИНФРАКРАСНОЙ ОБРАБОТКИ ПОЛИМЕРНЫХ ПОКРЫТИЙ ПРИ ВОССТАНОВЛЕНИИ КОРПУСНЫХ ДЕТАЛЕЙ АВТОТРАКТОРНОЙ ТЕХНИКИ

Application of polymer coatings for restoration of worn-out bearing holes in housing parts of automotive equipment provides multiple increase of their service life, reduction of repair costs, improvement of reliability. The highest efficiency is achieved by applying elastomeric coatings. To cure the material and achieve high mechanical properties, the coating, after application, is subjected to thermal treatment by convective or thermoradiation methods. Coatings after treatment by a thermoradiation method, in comparison with convective, have significantly lower porosity and higher quality. A model of infrared heating of type I body parts (gearbox housing, car and tractor transfer case housing) has been developed, which takes into account the heat capacity of the material and the design parameters of the part, the ambient temperature and the steady temperature of the part during heating, the design parameters of the infrared radiation installation. The model allows you to calculate the rate of temperature increase and the time of heating the part to the required temperature by infrared heating. The article describes in detail the algorithm and provides a computer program for calculating the structural and technological parameters of the infrared processing plant for elastomeric coatings applied during the restoration of bearing holes in the body parts of the equipment. Heating of the gearbox housings of GAZ-24 and GAZ-53A cars showed a high coincidence of the design and experimental values of infrared heating parameters. The difference between the actual heating temperature of the body part and the design temperature is from 1.5 to 2.4%, the heating time is from 6.1 to 8.2%, which is a confirmation of the correctness of the developed method for calculating the structural and technological parameters of infrared installations. An experimental assessment of the quality of elastomeric coatings after heat treatment by various methods was carried out. Compared to the convective method, after infrared treatment, the quality of elastomer coatings increased F-40S: the area of the destroyed coating decreased by 1.33 times, the concentration of pores in the coating - by 1.24 times.

Gear Fault Diagnosis Based on Variational Modal Decomposition and Wide+Narrow Visual Field Neural Networks

In modern industrial production, rotating machinery plays an important role. The gears in this machinery adjust the speed and transmission of torque. Therefore, when the gear fails, it is very important to be able to diagnose the fault quickly and accurately. Gear vibration signals are often used in gear fault diagnosis, but the fault signal is often overwhelmed by noises. To enable the scientific and efficient detection of faults, this study proposes a gear fault diagnosis method based on variational modal decomposition (VMD) and wide+narrow visual field neural networks (WNVNNs), namely VMD-WNVNN. VMD-WNVNN consists of two stages. In the feature extraction stage, VMD and Pearson correlation coefficients are used to decompose and reconstruct the original data to obtain the features of these data in the frequency domain. In the classification stage, WNVNN is used to classify the data based on features. The final results of the gear fault diagnosis experiments show that this method not only has higher classification accuracy but also has higher classification stability than other recently proposed methods. Note to Practitioners—The gearbox is composed of many mechanical parts, such as gears, shafts, and bearings. Therefore, the vibration signal collected by the vibration sensor on the gearbox housing will contain the vibration signal of each part and the noise caused by processing errors. Therefore, if some methods can be used to efficiently extract the characteristic signals required for diagnosis in the data processing stage, the efficiency of fault diagnosis will be greatly improved. This article takes the health of gears as the research object and proposes a method that combines adaptive signal decomposition and deep learning technology. Experimental results show that this method has higher classification accuracy and classification stability than other methods proposed recently.

Dynamic Fatigue Analysis of High-Speed Trains Gearbox Using Copula Function

As a key component of the transmission system of high-speed trains, the reliability of gearbox is crucial to the overall reliability and driving safety of high-speed trains. In this work, a comprehensive reliability model for the key parts of the gearbox including the driving and driven gears, bearings, and gearbox housing is developed, which combines the strength degradation parameters obtained by P-S-N curves of the corresponding material, and a stress-strength interference model based on the Poisson distribution of random stress and the Wiener strength degradation process. Further, a nested Copula function reliability model of the gearbox series system is developed using the binary Frank Copula function considering the correlation of failures of different parts and different failure modes. This model realizes the dynamic reliability analysis of the gearbox under different failure modes. The reliability analysis of the key parts of the gearbox and the gearbox series system of high-speed train achieved with this model are in line with the engineering practice. This method enables dynamic tracking and monitoring of gearbox reliability during the service life of high-speed train.

Dynamic modelling of gearbox with multiple localized defects and its coupled vibration analysis

Gearboxes are one of critical components of railroad vehicles, aero-engines and other rotating machinery, and their health condition is crucial for the safe operation of these rotating machines. Fault signature extraction is a vital step for gearbox health condition monitoring. To this end, knowing the characteristics of fault signature is a prerequisite. Dynamic model is an effective tool for analysing the fault features of gearbox. However, in reality, the vibrations measured from the gearbox housing are usually coupled with the vibrations of the rolling bearings, the gear mesh and the gearbox housing, which are influenced by the friction, lubrication, surface roughness, etc., of each contact pair. Consequently, any dynamic model of individual components cannot accurately reflect the actual vibration behavior of the gearbox and also the resulted vibration response cannot match the vibrations measured from the gearbox housing. To resolve this problem, this paper develops a comprehensive dynamic model to analyze the vibration response of a gearbox with multiple localized defects by coupling the effects of spur gear mesh, deep groove ball bearings, time-varying displacement excitation of the bearing caused by localized defects, time-varying mesh stiffness (TVMS) of the gear, and mixed elastohydrodynamic (EHD) lubrication. The coupled vibrations of the gearbox housing can then be obtained to analyze the vibration behavior of a gearbox with multiple localized defects. In addition, the influences of the relative motion of the bearing rollers and flexible cage on the gearbox vibration are analyzed. At last, the proposed dynamic model is validated by experiments.

Advanced method of including housing stiffness into calculation of gear systems

One of the central goals during the design of helical gear systems is the achievement of a well-distributed contact load in the gear mesh. An equal load distribution is a key factor for a high load carrying capacity, the economic use of materials and a long lifetime. Mesh misalignment can be caused by tooth deflections, manufacturing deviations or elastic deformation of the shaft-bearing system and the gearbox housing. Those deformations have to be taken into account during the design process of adequate tooth-flank geometry. Elastic deformations of gearbox housings can be significant, especially in the case of automotive applications with aluminium cases. This paper presents an advanced method of including housing stiffness into the calculation of gear systems. A validation of the approach is carried out by comparing the calculated deformations with measurements of a static test rig of a hypoid gearbox.Many calculation programs offer the opportunity to analyse the deformation behaviour of the shaft-bearing-housing system. Most of the components in these programs are described by analytic approaches. However, components that are geometrically more complex, like the housing or planet carriers cannot be represented as easily as that by analytic expressions. There are several alternatives to take into account the elasticity of those objects. One way is to model the stiffness of the bores using imported stiffness matrices. These matrices contain the elasticity of the bores itself as well as crossover influences between the bearings. The reduced stiffness matrices may be the result of a static reduction of the geometry using the finite element method (FEM). As state of the art, the reduction is mostly carried out at the centre points of the bearing bores. The proposed advanced method uses the static reduction of geometries on several points at the bores, distributed over the circumference. This approach offers a more detailed modelling of the elastic behaviour of complex geometries within the analytic deformation calculation of gear systems. To validate the advanced approach, the calculation results of the elastic deflections of the shaft-bearing-housing system is compared with measurements of a static test rig. In the course of these comparisons, the influence of different modelling methods of gearbox housings on the accuracy of the calculation results is discussed.

Sensor Screening Methodology for Virtually Sensing Transmission Input Loads of a Wind Turbine Using Machine Learning Techniques and Drivetrain Simulations

The ongoing trend of building larger wind turbines (WT) to reach greater economies of scale is contributing to the reduction in cost of wind energy, as well as the increase in WT drivetrain input loads into uncharted territories. The resulting intensification of the load situation within the WT gearbox motivates the need to monitor WT transmission input loads. However, due to the high costs of direct measurement solutions, more economical solutions, such as virtual sensing of transmission input loads using stationary sensors mounted on the gearbox housing or other drivetrain locations, are of interest. As the number, type, and location of sensors needed for a virtual sensing solutions can vary considerably in cost, in this investigation, we aimed to identify optimal sensor locations for virtually sensing WT 6-degree of freedom (6-DOF) transmission input loads. Random forest (RF) models were designed and applied to a dataset containing simulated operational data of a Vestas V52 WT multibody simulation model undergoing simulated wind fields. The dataset contained the 6-DOF transmission input loads and signals from potential sensor locations covering deformations, misalignments, and rotational speeds at various drivetrain locations. The RF models were used to identify the sensor locations with the highest impact on accuracy of virtual load sensing following a known statistical test in order to prioritize and reduce the number of needed input signals. The performance of the models was assessed before and after reducing the number of input signals required. By allowing for a screening of sensors prior to real-world tests, the results demonstrate the high promise of the proposed method for optimizing the cost of future virtual WT transmission load sensors.

On-Machine Measurements for Aircraft Gearbox Machining Process Assisted by Adaptive Neuro-Fuzzy Inference System

This paper deals with the development of dimensional control technology for the production of accessory drive train (ADT) gearbox housing, according to the closed door technology approach. The work presents the methodology of the final inspection of bearing seat position deviation by replacing the coordinate measuring machines (CMMs) with a computerized numerical control (CNC) machine and adaptive neuro-fuzzy inference system. The results of the work indicated that correct solutions were obtained. In addition, the technological process of manufacturing is fully automated and performed entirely on the production line.

Robotised Geometric Inspection of Thin-Walled Aerospace Casings.

This paper deals with the development of dimensional control technology for the production of ADT (accessory drive train) gearbox housing. The project included the development of a robotic geometry inspection station for thin-walled aerospace casings. Laser profilometers from two brands, Cognex and Keyence, were used to measure. A proprietary software solution for arc measurements is presented. The obtained solutions were compared and verified in accordance with the requirements of the manufacturer Pratt and Whitney Rzeszów S.A. The results of the work indicated that correct solutions were obtained with a very large reduction in control time. In addition, the measurement is fully automated and transferable to the company’s electronic systems.

Feasibility Evaluation of Milling Designs Using Multi-Agent Systems

AbstractDuring product development, many decisions have to be made that affect the entire product life cycle and often lead to errors that cause additional effort. To proactively support the engineer in evaluating his design in a CAD program, in this paper an approach to evaluate milling designs using a multi-agent system (MAS) is presented. The CommonKADS method is used and the MAS is validated against an application example of a gearbox housing that has been checked for design guidelines, standards, and tool or machine portfolios.

Lightweight Design of Gearbox Housing of Baja Racing Car Based on Topology Optimization

In view of the National Undergraduate Baja Contest, an initial model is established for the reducer. According to the calculated force of the transmission part, the reinforcing ribs of the bearing hole are optimized and the initial model is optimized and checked several times using the topology optimization module of ANSYS. The safe and reliable housing model with a weight reduction of 35.82% makes full use of the material properties, thus contributing to lightweight of the whole vehicle under the premise of sufficient strength.

Improvements to gearbox acoustics via thrust collars

Thrust collars relieve the gearbox housing of the axial force and tilting moments generated by helical gears. The different transfer path also reduces the vibration excitation of the housing due to meshing, which could lead to improved acoustics. This paper presents measurements of noise level reduction of an experimental gearbox. A gearbox dynamics simulation model is used to investigate the effects resulting from the inclusion of thrust collars.

Fault Detection of Planetary Gears Based on Signal Space Constellations.

A new method to process the vibration signal acquired by an accelerometer placed in a planetary gearbox housing is proposed, which is useful to detect potential faults. The method is based on the phenomenological model and consists of the projection of the healthy vibration signals onto an orthonormal basis. Low pass components representation and Gram–Schmidt’s method are conveniently used to obtain such a basis. Thus, the measured signals can be represented by a set of scalars that provide information on the gear state. If these scalars are within a predefined range, then the gear can be diagnosed as correct; in the opposite case, it will require further evaluation. The method is validated using measured vibration signals obtained from a laboratory test bench.

Pneumatic automation of the assembly of spherical bearing and pin header into the gearbox housing

With the advent of computers and technology, remarkable changes are observed in the automotive industries in recent decades. The implementation of automation and advanced processing techniques have resulted in revamping of the production systems. Especially assembly processes which are based on repetitive tasks are greatly influenced by automation as it results in the enhancement of productivity by avoiding human intervention. The productivity and profit directly depends on the efficiency of the assembly processes especially in case of small scale industries. In this regard, automation can bring remarkable changes in performance of assembly processes. The present work attempts to design a piece of semi-automatic equipment powered by pneumatics for carrying out the repetitive task of assembling of components at small-scale automotive industries, for achieving enhanced productivity as compared to the currently adapted manual assembly process. Parts to be assembled are a spherical bearing and a pin header into the gearbox housing. This equipment was designed on a CATIA V5 platform. The manuscript presents the design of all the components of the proposed equipment and also the working of the system. The proposed new equipment is expected increase the productivity and also decrease the human errors caused during the manual assembly process.

Design and development of all wheel drive transmission system for an all-terrain vehicle

An All-Wheel Drive Transmission system powered by a 10 HP Briggs & Stratton engine is designed for a single-seater all-terrain vehicle. Because of the engine power limitation, it's important to reduce the vehicle's weight and improve its performance. The aim is to increase the traction of the vehicle and it must be able to climb high grades, cross slippery mud pools, and snow tracks with minimum drive slip. While performing, the system must be reliable and not fail under any circumstances. The study focuses on the optimized calculation of engine performance, vehicle mass, air drag, rolling resistance, continuously variable transmission (CVT) shifting, gearbox reduction ratio, gear selection, shaft, and casing. The design and analysis process includes the development of a compound gear train with gears having a minimum diameter and face width, to lower the rotational inertia of the system and included the calculation of static failure from contact and bending stresses, gearbox housing, shafts, and bearings. All components are designed in Solidworks 2016 and analyzed in Ansys Workbench 19.2.

Dynamic Reliability Evaluation of High-Speed Train Gearbox Based on Copula Function

As a key component of the high-speed train transmission system, the reliability of the gearbox directly affects the reliability and driving safety of the high-speed train. Taking the key parts in the gearbox: driving gear, driven gear, gearbox housing and bearing as the research object, the dynamic reliability of the gearbox is evaluated. First, combined with classical stress-strength interference theory, the number of stochastic loads is regarded as a Poisson process, and the strength degradation is described by the Gamma process, the Gamma strength degradation parameter of each part is determined from the part material or the part’s P-S-N curve, and the reliability model of each key part of the gearbox is obtained. Second, the gearbox is regarded as a series system, and the Gumbel Copula function is introduced to deal with the nonlinear correlation between different parts and between different failure modes of the same part. The nesting relationship of the Copula function is determined, the parameter values of the Gumbel Copula function are determined based on the kernel density estimation and maximum likelihood estimation method, so as to establish the dynamic reliability model of the gearbox system and realize the evaluation of the dynamic reliability of the gearbox. The evaluation results show that the method for evaluating the reliability of high-speed train gearboxes is in line with engineering practice. The evaluation method has practical significance for the reliability check, optimization design and dynamic tracking of the gearbox reliability during the service period of the high-speed train gearbox.

Design, Simulation and Optimization of an Additive Laser-Based Manufacturing Process for Gearbox Housing with Reduced Weight Made from AlSi10Mg Alloy

The gas turbine engine’s (GTE) development aims for the increasing the efficiency, strength, reliability and safety of its components. To create competitive engines, housing parts and components with high functionality and reduced weight are needed. Especially difficult in the design and production are the gearboxes for aviation GTE. Traditional technologies based on precision casting or material forming operations have significant limitations due to the complexity of fulfilling multiple different requirements. Nowadays, one of the progressive production techniques is additive manufacturing. The article presents the results of computational and experimental studies that substantiate the applicability of laser additive technology to reduce the mass of body parts by up to 15% while ensuring their strength properties. The physical and mechanical characteristics of aluminum alloys acceptable for the manufacturing of housing parts were analyzed. The necessary characteristics of the powder alloy of the Al-Si system and the technological parameters of the L-PBF of the modified housing of the gear reducer are established. Using the finite element method (FEM) the L-PBF process was numerically simulated and the technological modes for synthesis of the AlSi10Mg alloy powder were optimized. With the help of a serial 3D printer ProX320DMP, the prototype of a gear housing was manufactured.

Cost optimization of two-stage helical gearboxes with second stage double gear-sets

In practice, the cost of a gearbox plays a very important role in the trade. Therefore, reducing the cost of gearboxes is an important task not only when manufacturing the gearboxes but also when designing them. In order to reduce the cost of a gearbox, there are many solutions in which determining the optimal partial gear ratios of a gearbox is an effective measure. This is because it not only the size, the mass but also the cost of a gearbox depends greatly on the partial gear ratios. This work presents a method for calculating the cost function of two-stage helical gearboxes with second-stage double gear-sets based on the mass of the components that construct the gearbox. The cost objective function is minimized to achieve the optimal transmission ratios. Furthermore, screening experiments are carried out with nine important input parameters that have significant effects on the optimum transmission ratio of the second stage. These parameters are the total gearbox ratio, the coefficient of wheel face width of the first stage, coefficient of wheel face width of the second stage, the allowable contact stress of the first stage, the allowable contact stress of the second stage, the output torque, the cost of gearbox housing, the cost of gears, and the shaft cost. The experimental results of were analysed by using the Analysis of Variance (ANOVA) method with the help of Minitab 19 software. The results demonstrate that the effective weight of the input parameters and their interactions on the output response was investigated. Also, a regression model for computing the optimal transmission ratio of the second stage was proposed. This brings significance not only in the design process but also in manufacturing since the gearbox cost can decrease

Design and analysis of E-glass gear box housing in tractor and optimization of its design parameters

A significant part of an automobile is the gear box (tractor) casing. The primary objective of using the Gearbox casing is to embrace and allow the transmission of the Gearbox. The Gearbox is a mechanism that regulates speed or torque between the flywheel and the differential. The main shaft and lay shaft with gears equipped embraces the gear box. This paper deals with the modeling and study as an alternative material of the gear box casing for a tractor with E-Glass. Through the development of the simulation software platform ANSYS, it is analyzed statically with different design parameters such as web thickness, gear box housing depth and gear box housing thickness. In order to determine the stress produced and deformation degree, the gear box with traditional Grey cast iron is analyzed; it is then compared with the housing of the E-Glass Gear box. The outcome will be studied and evaluated after study, various combinations of design parameters were used to achieve the design that minimum output in failure at higher load s has better deformation characteristics. Finally, in order to design the gear box housing, an optimized design parameter is obtained.[1]