Detta arbete beskriver förarbete och konstruktion av en stegmatare som sorterar och orienterar vevstakar för en takttid på tio sekunder. Industrier är ofta beroende av materialhanteringsutrustning där olika processer säkerställer någon form av sortering eller orientering, vilket styrker arbetets relevans. Detta har skett genom att dela in maskinen i två huvudfunktioner; trappfunktionen, som försorterar och transporterar vevstakarna vidare till andra huvudfunktionen; orienteringsfunktionen, där orienteringen sker. Genom att tillämpa metoder inom; konstruktion & tillverkning, feleffektsanalys och programvaror för materialdatabashantering, datastödd design, samt numerisk hållfasthetsanalys kunde en konstruktion utformas som speglar de aspekter som kännetecknar en genomtänkt produkt. Sju olika designmetoder användes för att generera och utvärdera idéer i flera itererande steg. Tio undersökande experiment utfördes som ytterligare utvärdering av koncept samt underlag för vidare beräkningar och slutsatser. Utformningen av stegmataren resulterade i en enkelverkande lutande trapp med två rörliga trappsteg och ett statiskt mellan dem för överföring. En enkelmatning efter trappen i form av ett “skovelhjul” säkerställer att vevstakarna levereras en-och-en till orienteringsfunktionen samtidigt som den garanterar takttiden. En orienteringsfunktion bestående av ett “rullband” som med hjälp av friktion och tyngdpunktsförskjutning orienterar vevstakarna med vevänden först. Slutligen studerades tre kritiska områden i konstruktionen för vidare analys med finita element-metoden med godkända resultat. Samtliga mål för projektet uppnåddes, exempelvis har stegmataren färre unika komponenter än befintliga lösningar. Ambitionen var att utforma stegmataren med en låg grad av komplexitet och utan sensorer har genomsyrat hela projektet, vilket även har uppnåtts. / This work describes the preparatory work and construction of a step feeder that sorts and orients connecting rods in a cycle time of ten seconds. Industries are often dependent of different material handling operations which assures a specific material orientation, which validates the importance of this work. This has been done by dividing the machine into two main functions; Stair case-function, which pre-sorts and transports the connecting rods further to the second function, the orientation- function where the orientation is performed. By using methods such as; design for manufacture & assembly, failure mode & effects analysis and softwares for material database handling, computer aided design and numerical strength analysis a construction could be formulated which reflects the aspects that characterize a well-planned product. Seven different design-methods were used in order to generate and evaluate ideas in several iterated steps. Ten investigative experiments were conducted as an additional evaluation of concepts and as a basis for further calculations and conclusions. The formulation of the step feeder resulted in a single-acting stair with two moving stairs and a static between them for transfer. A single-feeder after the staircase in the shape of a “paddle wheel” ensures that the connection rods are delivered one-by-one to the orientation-function while also ensuring the cycle time. An orientation-function consisting of a “conveyor“ that with the aid of friction and an offset of the center of gravity orients the connecting rods with the crankshaft-end first. Lastly were three critical areas in the construction further examined with finite element method with passing results. All objectives for the project were achieved, the step feeder have for instance fewer unique components than existing solutions. The ambition was to design the step feeder with a low grade of complexity and without sensors have permeated throughout the entire project, which also was achieved.

Connecting rod are found in most combustion engines and transmits thrust from the piston to the crankshaft. The connecting rod needs to withstand forces from the piston and inertia forces which results in axial tension, compression stresses and bending. Today the most common manufacturing techniques in automotive industry are drop-forging, die-casting and the Powder Metallurgy technique used is powder-forging. In this Master Thesis different connecting rod designs for a single press PM manufacturing process were created and evaluated as a part of Höganäs AB's Total Powder Metal Car project, TPMC. This paper will serve as a basis for future connecting rod projects at Höganäs AB when choosing a suitable connecting rod design. The main objective of this Master Thesis is to evaluate different designs in regards to the following: Buckling strength Fatigue life Manufacturing rating The study shows that there is evidence that a single pressed connecting rod is possible. No absolute answer of which design is the best is given in this paper since in depends on different parameters and application. For each parameter examined there are results presented and arguments for and against each design which can aid designers in future work. Suggestions of improvement on both the method and on the designs are presented in respect to the results. The improvements may potentially increase the fatigue life, buckling strength and improve manufacturability.

This work was carried out to study the effect of shot-peening on the fatigue behaviour of carbon steels. Differently heat treated medium and high carbon steel specimens were selected. Medium carbon steels, AISI 1141 and AISI 1151, were respectively air cooled and quenched-tempered. A high carbon steel, C70S6 (AISI 1070), was air cooled. The other material was a powder metal (0.5% C) steel. Each group of steels was divided into two. One was shot-peened. The other half remained in their original conditions. All were fatigue tested under fully reversed (R=-1) tension-compression loading conditions. Microhardness tests were carried out on both the grip and gage sections of selected non shot-peened and shot-peened specimens to determine the hardness profile and effect of cycling. Shot-peening was found to be deeper on one side of each specimen. Compressive residual stress profiles and surface roughness measurements were provided. Shot-peening increased the surface roughness from 0.26±0.03µm to 3.60±0.44µm. Compressive residual stresses induced by shot-peening reached a maximum of -463.9MPa at a depth of 0.1mm.The fatigue limit (N≈106 cycles) and microhardness profiles of the non shot-peened and shot-peened specimens were compared to determine the material behaviour changes after shot-peening and cycling. Also their fatigue properties were related to the manufacturing process including heat and surface treatments. Comparing the grip and gage microhardness profiles of each steel showed that neither cyclic softening nor hardening occurred in the non shot-peened condition. Cyclic softening was apparent in the shot-peened regions of all steels except powder metal (PM) steel. The amount of softening in the shot-peened region was 55.0% on the left side and 73.0% on the right in the AISI 1141 steel , 46.0% on the left side and 55.0% on the right in the C70S6AC steel and 31.0% on the right side in AISI 1151QT steel. Softening was accompanied by a decrease in the depth of surface hardness. It is suggested that although the beneficial effects of shot peening, compressive residual stresses and work hardening, were offset by surface roughness, crack initiation was more likely to occur below the surface. Surface roughness was not a significant factor in controlling the fatigue lives of AISI 1141AC and C70S6 steels, since they were essentially the same for the non shot-peened and shot-peened conditions. Shot-peening had very little effect on the push-pull fatigue limit of C70S6 steel (-2.1%), and its effect on AISI 1141AC steel was relatively small (6.0%). However, the influence of shot-peening on the AISI 1151QT and PM steels was more apparent. The fatigue limit of the PM steel increased 14.0% whereas the fatigue limit of the AISI 1151QT steel decreased 11.0% on shot peening.

This work was carried out to study the effect of shot-peening on the fatigue behaviour of carbon steels. Differently heat treated medium and high carbon steel specimens were selected. Medium carbon steels, AISI 1141 and AISI 1151, were respectively air cooled and quenched-tempered. A high carbon steel, C70S6 (AISI 1070), was air cooled. The other material was a powder metal (0.5% C) steel. Each group of steels was divided into two. One was shot-peened. The other half remained in their original conditions. All were fatigue tested under fully reversed (R=-1) tension-compression loading conditions. Microhardness tests were carried out on both the grip and gage sections of selected non shot-peened and shot-peened specimens to determine the hardness profile and effect of cycling. Shot-peening was found to be deeper on one side of each specimen. Compressive residual stress profiles and surface roughness measurements were provided. Shot-peening increased the surface roughness from 0.26±0.03µm to 3.60±0.44µm. Compressive residual stresses induced by shot-peening reached a maximum of -463.9MPa at a depth of 0.1mm.The fatigue limit (N≈106 cycles) and microhardness profiles of the non shot-peened and shot-peened specimens were compared to determine the material behaviour changes after shot-peening and cycling. Also their fatigue properties were related to the manufacturing process including heat and surface treatments. Comparing the grip and gage microhardness profiles of each steel showed that neither cyclic softening nor hardening occurred in the non shot-peened condition. Cyclic softening was apparent in the shot-peened regions of all steels except powder metal (PM) steel. The amount of softening in the shot-peened region was 55.0% on the left side and 73.0% on the right in the AISI 1141 steel , 46.0% on the left side and 55.0% on the right in the C70S6AC steel and 31.0% on the right side in AISI 1151QT steel. Softening was accompanied by a decrease in the depth of surface hardness. It is suggested that although the beneficial effects of shot peening, compressive residual stresses and work hardening, were offset by surface roughness, crack initiation was more likely to occur below the surface. Surface roughness was not a significant factor in controlling the fatigue lives of AISI 1141AC and C70S6 steels, since they were essentially the same for the non shot-peened and shot-peened conditions. Shot-peening had very little effect on the push-pull fatigue limit of C70S6 steel (-2.1%), and its effect on AISI 1141AC steel was relatively small (6.0%). However, the influence of shot-peening on the AISI 1151QT and PM steels was more apparent. The fatigue limit of the PM steel increased 14.0% whereas the fatigue limit of the AISI 1151QT steel decreased 11.0% on shot peening.

Submitted by RAFAEL AGUERA REZENO DA SILVA null (aguera.feg@gmail.com) on 2016-04-10T23:05:59Z No. of bitstreams: 1 Dissertação_Aguera.pdf: 5287076 bytes, checksum: 018a793b7d2956814528ec0cb549cc66 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-04-12T17:53:04Z (GMT) No. of bitstreams: 1 silva_rar_me_guara.pdf: 5287076 bytes, checksum: 018a793b7d2956814528ec0cb549cc66 (MD5) / Made available in DSpace on 2016-04-12T17:53:04Z (GMT). No. of bitstreams: 1 silva_rar_me_guara.pdf: 5287076 bytes, checksum: 018a793b7d2956814528ec0cb549cc66 (MD5) Previous issue date: 2016-02-16 / Em bielas automotivas, os parafusos atuam de maneira a manter a união entre capa e haste, suportando as cargas trativas, compressivas e transversais originadas no olhal maior. Para tais componentes, o dimensionamento de juntas aparafusadas torna-se complexo, visto que a disposição dos parafusos e a geometria do mancal conduzem ao surgimento de esforços excêntricos à face de fratura, elevando a criticidade do projeto. Em vista disso, e do reduzido número de publicações sobre o assunto, o presente trabalho propôs uma “abordagem híbrida” para a análise de juntas aparafusadas em bielas anguladas, utilizando resultados obtidos a partir de um modelo de elementos finitos simplificado e as ferramentas contidas no roteiro VDI 2230 parte 1. Além disso, foi avaliada a influência do fenômeno de abertura unilateral sobre a vida em fadiga dos fixadores utilizados em bielas anguladas, analisando os resultados obtidos de modo a desenvolver um critério de avaliação para a fadiga desses componentes. A despeito das restrições, a abordagem numérico-analítica desenvolvida demostrou-se atraente, tanto pelo baixo custo computacional associado, quanto por sua precisão, principalmente na determinação da força tensora residual mínima para a prevenção de abertura, mostrando-se adequado para processos de otimização multiparamétricos, selecionando designs promissores passíveis de posterior avaliação através de modelos refinados. Já as análises de influência do fenômeno abertura não apresentaram alterações sensíveis nos níveis de força adicional dos fixadores, fato esse relacionado com a posição dos pontos de abertura em relação ao parafuso e ao mancal. Apesar disso, as simulações realizadas demonstraram que as condições de carregamento avaliadas não influenciaram no diagrama de Haigh local dos nós críticos de cada fixador, o que sugere o uso de resultados extraídos de ensaios de fadiga como variáveis de entrada para simulações em juntas de bielas, incluindo assim as influências benéficas do processo de manufatura. / Connecting rods screws maintain the connection between cap and shank supporting the tensile, compressive and transversal loads applied on the big end. In this case, the design of bolted joints become complex since the screw’s position and bearing geometry lead to eccentric forces acting on the joint split line. Due to that and the reduced number of publications on the subject, this dissertation aims to develop a "hybrid approach" for the analysis of bolted joints in angled connecting rods, using results from a simplified finite element model as input for the VDI 2230 part 1 guideline. In addition to that, this study evaluates the influence of unilateral opening phenomenon on fasteners fatigue life, analyzing the results in order to develop a criterion for fatigue analysis of connecting rod bolts. Despite the restrictions, the “hybrid approach” proved to be attractive due to the low computational cost and accuracy, especially for the calculation of minimal residual tensile force to prevent opening, being suitable for multiparametric optimization during project early phases. The opening phenomenon showed no significant changes in fastener’s additional forces, fact related to the position of joint opening points. Nevertheless, the simulations showed that the loading conditions did not influence on the local Haigh diagram of critical nodes, which suggests the use of fasters fatigue tests as input variables for fatigue simulations, thus including the beneficial influences of the manufacturing process.

Composite materials hold great potential for the replacement of traditional materials in machines utilized on a daily basis. One such example is within an engine block assembly where massive components inherently reduce the efficiency of the system they constitute. By replacing metal elements such as connecting rods, cylinder caps, or a crank shaft with composite alternatives, a significant increase in performance may be achieved with respect to mechanical strength, thermal stability, and durability, while also reducing mass. Exploration of this technology applied to a connecting rod geometry was investigated through a combination of process development, manufacturing, numerical analysis and testing. Process development explored composite material options based on experimental characterization, fabrication, and machining methods. Finite element analysis provided insight into model and data accuracy, as well as a basis for study on a unidirectional composite I-beam geometry. Destructive testing of the composite connecting rods provided data for a strength to weight ratio comparison with the original steel component. The composite connecting rods exhibited weight savings of 15%-17% that of the steel component. The rod made of woven composite material exhibited an elastic modulus of 68.1 Msi in its linear behavior before failure, thereby exhibiting a higher stiffness than the steel rod tested. Although the failure strengths were 25% below the required design load, the calculated strength to weight ratios showed favor for the composite alternatives.

This master's thesis deals with the process of machining a forged connecting rod in cooperation with the company Zetor Tractors a.s. The first chapter of the thesis is focused on a detailed introduction of the company. The second chapter includes an elaborate analysis of the technical documentation and requirements concerning the making process of the subject of study, specifically the construction of the connecting rod. In the third chapter, the current production technology is discussed and described in detail. The aim of the fourth chapter is to propose an innovative technology which can be used for the production of connecting rods in the required quality. The fifth chapter is aimed at testing the newly designed technology. In the final, sixth, chapter, a technical and economical evaluation of the proposed procedure is performed.

The purpose of this thesis is to design a powertrain of petrol three-cylinder radial aircraft engine with the main parameters specified (bore, stroke, etc.), balancing inertia forces, stress analysis and determining of fatigue of the selected parts.

This diploma thesis deals with a design of a stationary engine connecting rod, its stress analysis and its safety factors. The thesis is divided into several parts. At the beginning there is a short research of connecting rods construction and a description of the engine. Then the main dimensions of a piston group and a connecting rod are defined and its 3D model is created. Next, the calculations of forces acting on the connecting rod in the crankshaft mechanism, are carried out. The following part deals with a stress analysis of the model created by MPK. From the obtained stress results, the safety factor at fatigue limit in chosen places of the connecting rod is calculated. In the conclusion, the results of the stress analysis and set safety factor level, are recapitulated.

The purpose of this thesis is the design of a radial spark-ignition engine in two layout variations, the stress analysis of selected components using the finite element method, the eventual optimization of selected components and the determination of safety on their most strained locations.