Preventive Maintenance and Inspection †Free Samples to Students

Question: Discuss about the Preventive Maintenance and Inspection. Answer: Introduction The chassis is mostly concerned on the lower part of the body of the automobile such as the frame, suspension, tires, driveline and the engine .among the mentioned parts, the frames is taken as the core part of the chassis of the automobile. The frame basically offers the support to the components which are mounted on the vehicle. Besides the duty of supporting the load , the suspension and the frame transfers the stresses and the loads to the structure of the vehicle, which includes the brake torque forces and the drive forces which make the vehicle to move.in order to offer support to the load and forces , the frame is required to be rigid enough . Besides, it must also be flexible enough to be able to sustain the twist and shock loads which are encountered in the road under different conditions(Administration, 2009). The frame of the chassis should be strong enough to withstand the shocks and the vibrations. It consists of the side member which are connected to the side members which are attached to the side cross members .besides the strength of the chassis frame management, the design of the chassis should significantly consider the stiffness of the chassis or in other terms the bending and the torsion characteristics. Sufficient torsional stiffness is important when one wants to achieve the handling characteristics. The chassis is normally designed such that they take into consideration the strength and the stiffness. Conventionally, the design is more concerned with the strength first and thereafter emphasize on the increasing the stiffness while paying less attention to the weight of the chassis. Such design procedure comprises the addition of structural loads across the members to the ones which exists in the chassis with the aim of increasing the torsional stiffness. This results in an inc rease in the weight of the frame which overall minimizes the efficiency of the fuel and increases the production cost due to the additional material. Hence, the motivation of this research project is to offer all the three aspects which include, the strength, stiffness and reduced weight. Besides, the aim of the research is to obtain the reduced weight of the component and satisfy the requirements for the loads and stresses. This process of attaining the desired structural performance is also referred to as structural optimization. The analysis of stress and loads of the structural systems are easily enabled by the help of a finite element analysis tools. The constraints for the optimization includes the limitations which arise from the strength stiffness and weight(Johnson, 2012). Research question and objectives Does the minimization of chassis weight is significant in the consumption of fuel Is the method of finite element simulation a better method for the weight and design optimization? In the perspective of the practitioner, enumerate the effective techniques for the optimization of weight, do these techniques offer better performance The main aim of this research project is to minimize the weight of the chassis .the constraints of the optimized design come from the maximum strength and the requirements for the stiffness. The frame of the chassis consists of two side member which are connected using cross members. The design variable includes the locations of the members, the number of the members, the size of the side and the numbers of the cross, members .over the past years, finite element analysis tool has been widely used by many types of research more so in the subject of structural optimization. While performing an analysis on the weight of the frame of the chassis, a model which is optimized is being developed varying the parameters of both the crossbar and the sidebar helps in reducing the weight.in the application of the finite element analysis tool, the input variables are used in determining the output variable. In some cases, the number of the models produced are more than one. On the other hand, while performing all these, there may be an increase in the cost of production and also in the prior determination of the results to be obtained. hence, this study attempts to come with a suitable approach that combines the finite element analysis method with modelling techniques such that it will be easy to predict the shear and other stress experienced in the chassis frame .besides, the response surface method used employed in the met modeling since it is easier to estimate and it requires slower amount of input data as co pared to other techniques of met modeling(Bennett, 2 012). The chassis serves as the backbone whereby all the components of the vehicle get attached. For the chassis in the modern automotive, the automotive is anticipated to offer the mountings for the suspensions system, the steering wheel system, the fuel tank, the seats, the final drive and the engine drive system. Besides, the chassis should also be in a position to provide a distinct rigidity for the accurate handling of the chassis and also be able to offer protection to the passengers from any external impacts when the vehicle is in motion. In order to satisfy all these requirements, the chassis is supposed to possess a smaller weight such that it is able to minimize the inertia and tentative provision of effective performance. it should also pose the features of rigidity for the purposes of counteracting the fatigues emanating from the loads that will be carried by the automotive .taking a close look at the frame of the chassis, we realize that It comprises of a variety of components which are located differently and usually the components are made of heat treated alloy steel or at times made of cold rolled steel. The steel is the material which provides the chassis with the particular characteristics mentioned above. I.e. rigidity, lightweight, and toughness. Below is the diagram(Totten, 2017). Diagonal components Rear, Front, an intermediate component, Longitudinal side component, Requirements for a good chassis frame The ram must be able to provide sufficient support to the chassis The frame must be able to be light in weight but sufficiently strong The frame must be rigid enough The most conventionally used material for the making of the frame of the chassis is steel. The steel can be either cold rolled steel or at times heat treated steel. This is because of the lightweight nature of steel and also its strength management. Flexural loads these are loads which are produced by the vertical plane of the components and comprises of the engine torques, the weight of the passengers, the braking torques and the dead weight of the vehicle .also, the lateral components experience the road camber, side wind, and the cornering force (Parr, 2011) The torsional load this is caused as a result of the vehicle coming across bumps. Dynamic load this comes about as a result of the obstacles and the wheel impacts .this loads results into longitudinal and lateral loads. Moto Yama et al. (2014) came up with a welding process design tool that would assist in obtaining the optimal arc by the use of response surface method and the finite element method together with genetic algorithms. This integrated system was aimed at minimizing the induced distortion in the overall structure. A lap joint specimen was taken and four parameters i.e. lap joint fillet weld specimen was used in this paper. Four process parameters namely current, voltage, speed, and direction optimized of help in the prediction of the distortions structure. This effectively minimized the production cost and time Karaoglu et al. (2002) performed an analysis on the chassis of a truck having riveted joints using the finite element material analysis. The version of the ANSYS used for the determination of the solution was 5.3. obtaining the stress prior to the manufacturing is very significant for the purpose of enhancing the design .to attain the minimization of the magnitude of the stress near the joint that has been riveted, some parameters were varied including the connection plate thickness, the side member thickness and the length of the connection plate .from the numerical results obtained, the stress on the side member can be minimized by amassing the thickness of the side member. Besides, the length of the connection plate can also be increased. Karat et al. (2003) did an experiment and realized that aluminum when used for the manufacture of the chassis material significantly aided in minimizing the weight of the truck and also allow the increase in the payload. A technique known as variable section extrusion was employed in the molding the aluminum frame side rails. The optimization of the weight and the shape was done by the help of computer-aided engineering tool. Tee et al. (2007) did a study on the characteristic of the chassis vibrations which comprised the modes shapes and the natural frequencies. The feedback from the truck chassis indicated that there was the distribution of stress and displacement under different conditions of loading. The numerical analysis was performed using the finite element tool and the results demonstrated that the main disturbance of the chassis of the truck was road excitation since the natural frequency of the road excitation is within the excitation frequency of the road. The results from the shape of the mode helped in determining the locations where mounting was to be done such as for the suspension system. Buddy et al. (2008) employed the principle of TRIZ and some other parameters to aid the design of the body of the lightweight .the body was created using computer-aided design tool and then the data transfer to the CAE by the help of finite element tool. Thereafter an analysis was done and then the comparison is done using the same technique of the design and, manufacturing. The methodology applied in this research is based on secondary means of obtaining data and information. This implies that the research has been drawn from the existing sources of information i.e. internet sources and literature books. Besides, an experiment has been accompanied with calculations which justify the aforementioned research aims and objectives. A finite element analysis has also been provided which provides a justification for the structural optimization of the weight of the chassis. The structure of the research methodology is provided below The reduction of the weight of the chassis plays a significant role in providing various options for the consumption of fuel. Conventionally, the global design of the chassis is based on the considerations of the stiffness and the strength such that the design will first be conscious of the strength and then later give emphasis on the increase of the stiffness of the chassis without putting into consideration the weight of the chassis. Such a technique follows the principles of the addition of structural weight across the existing components in an attempt to increase the stiffness and thereby resulting to increases in weight and consequent reduction in the fuel efficiency. The size of the material is also increased. However, a design that takes into consideration the three basic aspects, reduced weight, adequate strength and adequate stiffness ensures that the fuel consumption is reduced(Gupta, 2009). It helps to prevent the effects of bump steer. From the dynamic of vehicles in regards to the safe handling and prediction of the steering system are supposed to remain intact as from the specifications and the design. The stiff chassis aids in achieving this. Besides, form the vehicle dynamics of steering suspension system the, system should be predictable since it is a dumping spring and if the chassis is not stiff, then it will get compromised. Stiff chassis helps to prevent the rattles and the squeaks in vehicles(Johnson, 2012). It is no doubt that finite element simulation method is desirable techniques for the optimization of the weight and design. Finite element analysis is a tool which cuts across all the engineering disciplines, mathematics, and physics.it has been widely applied in the analysis of structures, thermal and fluids. It generally entails some phases including Preprocessing in this phase, the analysis is tasked with coming up a finite element mesh to help in dividing the geometry of the subject into various sections for mathematical analysis. this phase applies boundary conditions and material properties Solution phase in this phases, the program is tasked with determining the governing matrix equations form the prototype and thereby provide various solutions for the primary subjects Post-processing phase in this phase, the analyst does a confirmation of the credibility of the solution while performing an examination of the primary quantities such as stress and then derive and provide more quantities. Advantages of finite element analysis tool for optimization Finite element analysis has a variety of advantages which make it suitable to be used as a design tool for optimization. For instance, a model of a new concept may be presented, but to be able to determine the real behavioral characteristics of the model under various conditions, it should be tested. After it has been designed, say by the use of computer-aided design tool, the finite element analysis tool helps in performing a deep analysis of the design(Kilcollins, 2012). Besides, there may be an existing product which requires some improvements or which is experiencing some challenges during operation. The finite element analysis helps in determining the cause and helps in optimization of the existing product thereby reducing the cost and as well speeding up the engineering change A finite element analysis tool also can be performed on ever-growing affordable computer workstations and also the home computers to assist in providing professional assistance. By being applied in the analysis and optimization in various aspects of engineering, science, and mathematics, finite element analysis tools helps in reducing the overall time and cost that could be spent while doing the related corrections(Gilles, 2009) Below are some of the justifications that finite element analysis tool is significant in optimization Roopesh Shroff et al. (2002), did a finite element analysis of the automotive chassis under the subject of natural frequency, stiffness, and strength. Since an algorithm requires a various number of structural analysis attain the optimum point, using the pipe and beam elements, the chassis model was developed and the optimization of weight using the first ordered methods done. Finally, the results were presented Linton et al. (2002) performed an analysis of a prototype chassis with the aim of determining the value of the torsional stiffness which was calculated to be 1330Nm/DEG. Additionally, the torsional stiffness value was to be optimized by the following procedure resulting into desirable values which were a 322 % increase in the efficiency Developing o a finite element basic validation model Discussion of the developed model Performing an improvement study of the design Performing an optimization study Karao?lu et al. (2002) analyzed performed an analysis on the chassis of a truck having riveted joints using the finite element analysis method. From various tests using the optimization tool, it was observed that the stress on the components side can be minimized by maximizing the thickness of the side of the component. If this fails, then the length of the connection plate can be equally increased. Wahab et al. (2009) did present on the analysis o the static stress which acts on the upper parts of the chassis. The analysis presented the manner in which the stress was distributed and how they were acting on the chassis. Besides, it presented the critical, sections which may result into failure in the near future. Hence, the researchers were able to appreciate the fact that the finite element analysis tool helped in reducing both the time and cots but also minimizing the number of physical tests that were to be carried on the model. Besides, the tool provided a loophole for modifications which were to be useful in the reduction of the stress and maximization of the strength of the chassis. Yilmazcoban et al. (2011) performed a finite analysis on nature of profiles used by manufacturers for the chassis and observed that most of them used thick profiles which were not economical and also had the effects of non-reliability. Hence concluded that the best profiles to be used for the manufacture of the chassis frame should be thin in width In the perspective of the practitioner, enumerate the effective techniques for the optimization of weight, do these techniques offer better performance Effective methods for weight optimization There are various methods which can be applied during the weight optimization of the chassis or any other material. The methods include Fea-Doe Hybrid Tool for Optimization This tool is a combination of the DOE and the finite element analysis techniques which provides an engineer with a wide range of study in the boundary conditions for the various design factors and also the analysis of impacts and related responses for the system interactions. This technique has been widely applied and some of the instances of their applications include Acherjee et al. (2012) performed an investigation on the transmission contour of the laser in the welding process by the help of both the design of experiments and the finite element analysis method. Finite element analysis is a tool which cuts across all the engineering disciplines, mathematics, and physics.it has been widely applied in the analysis of structures, thermal and fluids. It generally entails some phases including Preprocessing phase, Solution phase, and the Postprocessing Advantages of finite element analysis tool for optimization Finite element analysis has a variety of advantages which make it suitable to be used as a design tool for optimization. For instance, a model of a new concept may be presented, but to be able to determine the real behavioral characteristics of the model under various conditions, it should be tested. After it has been designed, say by the use of computer-aided design tool, the finite element analysis tool helps in performing a detailed analysis of the design. Besides, there may be an existing product which requires some improvements or which is experiencing some challenges during operation. The finite element analysis helps in determining the cause and helps in optimization of the existing product thereby reducing the cost and as well speeding up the engineering change A finite element analysis tool also can be performed on ever-growing affordable computer workstations and also the home computers to assist in providing professional assistance. By being applied in the analysis and optimization in various aspects of engineering, science, and mathematics, finite element analysis tools helps in reducing the overall time and cost that could be spent while doing the related corrections Karao?lu et al. (2002) analyzed performed an analysis on the chassis of a truck having riveted joints using the finite element analysis method. From various tests using the optimization tool, it was observed that the stress on the components side can be minimized by maximizing the thickness of the side of the component. If this fails, then the length of the connection plate can be equally increased. Linton et al. (2002) performed an analysis of a prototype chassis with the aim of determining the value of the torsional stiffness which was calculated to be 1330Nm/DEG. Additionally, the torsional stiffness value was to be optimized by the following procedure resulting into desirable values which were a 322 % increase in the efficiency Developing o a finite element basic validation model Discussion of the developed model Performing an improvement study of the design Performing an optimization study Roopesh Shroff et al. (2002), did a finite element analysis of the automotive chassis under the subject of natural frequency, stiffness, and strength. Since an algorithm requires a various number of structural analysis attain the optimum point, using the pipe and beam elements, the chassis model was developed and the optimization of weight using the first ordered methods done. Finally, the results were presented Response surface methodology (RSM) this technique is a tool used for the purposes of prediction and it is a collection of statistical techniques and the various mathematical techniques for the purposes of creation of an empirical model. This tool helps in the optimization of the output variable of the variable that depends on the various input parameters. This technique helps in minimizing the cost of the methods used in analysis such as finite element method and also associated unwanted responses. This technology has some advantages and limitations. The advantages include It allows for the use of irregular shapes and also the inclusion of additional design points It provides a lower data output data requirement when compared to other techniques During the optimization process, it does not assume the approximation structure thereby producing the best quality structure. The limitations include Normally the responses are assumed to be a smooth varying value in relation to the change in the parameters It only provides a single response at a time thereby making it difficult for engineers who are interested in obtaining the value of different parameters. This optimization tool has been applied by various researchers as illustrated below Venter et al. (1997) performed an RSM optimization to determine the response surface of approximation under various load conditions. The tools helped to eliminate the effects of noise due to the smooth response surface features. Besides, the smooth response provided for the application of an optimization based on a derivative during the process of the design. Motoyama et al. (2014) came up with an integrated system of the three methods for optimization which was aimed at helping in the reduction of the induced distortion of the overall welded structure. This technique was highly efficient and to demonstrate it, a lap joint fillet was used where the parameters including current, voltage, welding Gaped and direction were optimized. From the results, it could be concluded that the methodology applied help in reducing the time and cost Performance advantages of weight optimization technique FEA-DOE techniques Provides an engineer with a wide range of study in the boundary conditions for the various design factors and also the analysis of impacts and related responses for the system interactions A model of a new concept may be presented, but to be able to determine the real behavioral characteristics of the model under various conditions, it should be tested. After it has been designed, say by the use of computer-aided design tool, the finite element analysis tool helps in performing a deep analysis of the design. Besides, there may be an existing product which requires some improvements or which is experiencing some challenges during operation. The finite element analysis helps in determining the cause and helps in optimization of the existing product thereby reducing the cost and as well speeding up the engineering change A finite element analysis tool also can be performed on ever-growing affordable computer workstations and also the home computers to assist in providing professional assistance. Be being applied in the analysis and optimization in various aspects of engineering, science, and mathematics, finite element analysis tools helps in reducing the overall time and cost that could be spent while doing the related corrections RSM technique is a tool used for the purposes of prediction and it is a collection of statistical techniques and the various mathematical techniques for the purposes of creation of an empirical; model RSM tool helps in the optimization of the output variable of the variable that depends on the various input para Performance of finite element analysis of the frame The analysis starts from the validation proves as shown in the chart below The existing chassis model is created using the PTC Creo 3.0 as shown below and then saved in the IGES format which allows for the importation of the ANSYS workbench. The chassis is held with four supports i.e. two at the rear part and two at the front side.it experiences forces from both the body of the truck and the load it is carrying. Assuming the maximum load weight is 10000kg and is uniformly distributed along the length of the chassis. On the upper side, it experiences a load of 58860N(Durali, 2015). The analysis done with regards to the models of the chassis indicates that the utmost generated value of the von misses stress is 96.98MPa as shown in the figure above. Since the designs stress is obtained by diving the yield stress with the safety factor, i.e. Vidosic (1957) provides some recommendations on the values of the factor of safety for different materials under different conditions of loading. Besides, it is possible to directly determine the value of 1.5 to 2 for the common materials under the normal environmental conditions. From the result obtained, reduction of the magnitude of stress at a critical appoint is of much necessity since it helps in meeting the safety factor value requirements of the chassis of the truck. It is possible to modify the chassis of the truck to increase the safety factor value of the critical point usually, the allowable value of the shear stress is 360/3 = 120 Mpa(Navy, 2009). The von misss values generated are less than the allowable values for the design safety and they are shown in the figure below. The weight of the chassis model is equal to 321.25 Kg. Comparison of the analytical and calculated result Criteria Analysis result Calculated result Von-mises stress 96.98 N/mm2 95.43 N/mm2 Deformation 1.7072 mm 2.85 mm From the calculation result, stress and deformation occur only on one sidebar. Conclusion This research project entailed the determination of design with a minimum weight of the Eicher chassis frame. The design of this frame comprises of two major parts which are connected together with a variety of cross members .hence, the design variable s includes the lotion of the cross member, their number, and the size of both the cross and side members .this reduction is attained by the use of varying the parameters by the aid of an orthogonal array and then a finite element analysis done on the models to obtain a precise solution. This technique helps in saving both time and the cost of production. Besides, a comprehensive thesis research has been presented which clearly elaborates the objectives of the research which includes determining whether the minimization of chassis weight is significant in the consumption of fuels, whether the method of finite element simulation a better method for the weight and design optimization the effective techniques for the optimization of weight, do these techniques offer better performance(Kilcollins, 2012) References Shroff, R. (2002). 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