Introduction to Machine Design
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Introduction to Machine Design Recommended Books: - Machine Design, An Integrated Approach, by Robert L Norton - Mechanical Engineering Design by Joseph Shigley - Design of Machine Elements by M.F. Spotts
description
introduction to the basic machine design.
Transcript of Introduction to Machine Design
Introduction to Machine Design ll
Introduction to Machine Design
Recommended Books:Machine Design, An Integrated Approach, by Robert L Norton Mechanical Engineering Design by Joseph ShigleyDesign of Machine Elements by M.F. SpottsContentsWhat is machine designPrerequisites of the subjectDesign processDesign stagesMajor areas in Machine DesignCAD and CAEBasics of mechanics of materialsFactor of safetyCodes and StandardsBasic Machine Elements
What is Machine Design?Engineering design is a decision making process (often iterative) in which the basic sciences, mathematics, and engineering sciences are applied to convert resources optimally to meet a stated objective.Machine Design is the application of science and technology to devise new and improved productsProduct is any manufactured item including machine, structure, tool or instrument.Prerequisites of the subjectMathematicsMechanicsKinematicsMaterials EngineeringStrength of materialsManufacturing processPrerequisites of the subjectMechanics: It is the branch ofscienceconcerned with the behavior ofphysical bodieswhen subjected toforcesordisplacements.
Kinematics: It is the branch ofclassical mechanicsthat describes themotionof bodies without consideration of the causes of motion.
Prerequisites of the subjectMaterials Engineering: It is a branch of science which deals with the study of properties and behavior of engineering materials.The basis of materials science involves relating the desiredpropertiesand relative performance of a material in a certain application to the structure of the atoms and phases in that material.Prerequisites of the subjectStrength of materials: It deals with the behavior of materials under stresses and strains.
Manufacturing Process: A design engineer must have a good understanding about the constraints and benefits of various manufacturing processes, which is very important for the realization of any design.Applications of Machine Design
Applications of Machine Design
Applications of Machine Design
Applications of Machine Design
Applications of Machine Design
Di Pietro Compressed Air EngineDesign ProcessIdentification of needBackground ResearchGoal StatementTask SpecificationsSynthesisAnalysisSelectionDetailed DesignPrototyping and TestingMass ProductionDesign Process
Design Stages
Major areas in machine designInitial design conception (CAD)Strength analysis (CAE)Material selectionManufacturability (CAM)Economy SafetyEnvironmental effectsReliabilityComputer Aided Design (CAD)Computer-aided design (CAD) can be a defined as the way of creation, modification and optimization of a design by using computer system.By using a CAD software, we can generate2D draft/drawing files3D wireframe models3D surface models3D solid models.
Computer Aided Design (CAD)The design-related tasks performed by CAD system are:Geometric modeling.Engineering analysis.Design review and evaluation.Automated drafting.Parts classification and coding.Computer Aided Design (CAD)
Computer Aided Engineering (CAE)CAE (Computer-Aided Engineering) is the study of behavior of a product in different conditions with the help of computer.CAE software are used to analyze performance of products,without building prototypes.CAE software packages help designer to perform,Stress/Structural AnalysisFluid flow AnalysisThermal Analysis etc.
Stress analysis of Connecting Rod
CFD Analysis of F-1 Racing carCFD Animation
Thermal Analysis of Automobile Brake
Filling Analysis Injection MoldingCAD/CAM Methodology
Basics of mechanics of materialsNormal StressesShear StressesTorsional Stresses Bending StressesFatigue StressesTheories of Failure
Factor of Safety (F.O.S)Factor of Safety (F.O.S)
Factor of Safety (F.O.S)
Factor of Safety (F.O.S)
Factor of Safety (F.O.S)As the FOS in increased, the designed product become more reliable.But with the increase in the FOS, the weight and cost of material increases.Factor of safety for commercial aircrafts is in the range of 1.2 to 1.5.If FOS = 1, then the stress in the part becomes equal to the strength of the material, thus, failure occurs.
Choosing a Factor of Safety (F.O.S)
Choosing a Factor of Safety (F.O.S)Brittle materials are designed against the ultimate strength, so failure means fracture.Whereas, Ductile materials are designed against the yield strength, and are expected to give some visible warning before fracture.F.O.S (Ductile) = MAX (F1, F2, F3)F.O.S (Brittle) = 2 x MAX (F1, F2, F3)Codes and StandardsCode is a set of specifications for design, analysis and/or manufacturing of any thing.
Standard is a set of specifications of parts, materials or processes intended to achieve uniformity, efficiency and specific quality.
AGMA, AISI, ANSI, ASME, ISO, SAE, etc..Basic machine elementsShafts, keys and couplingsGearsBearingsJointsSpringsBrakes and clutchesThreads and screws
