Introduction to Manufacturing Engineering and Technology Course MAE 3344 Introduction to Manufacturing Engineering and Technology Mechanical Engineering Department Faculty of Engineering, Assiut University

What is Manufacturing? How do we make these?

The Book and Suggested Reading Manufacturing Engineering and Technology, 3rd Edition by S. Kalpakjain, published by Addison Wesley Suggested Reading The New Manufacturing Engineer by M.J. Terminie, published by The Society of Manufacturing Engineers, 1996 Designing for Economical Production by H.E. Trucks, published by the Society of Manufacturing Engineers, 1987 "Handbook of Product Design for Manufacturing," James G. Bralla, Editor, McGraw-Hill, 1986

Definition of "Manufacturing" "Manufacturing" is a process for converting ideas and market or customer needs into artifacts; Includes design, procurement, test, finance, human resources, marketing, etc. manufacturing is the conversion of raw materials into useful products Main Focus of This Course

Little "m" manufacturing is all about Creating shapes by various means and assembling these shapes into a useful product The processes used to transform raw material into finished products A physical product always has a shape Function Aesthetics These shapes are created by a wide variety of processes Students must remember that these processes exist only in the context of the larger Manufacturing process

People, money, machines and automation Manufacturing Customer needs People, money, machines and automation Societal pressures, Government regulations, company plans and policies, etc manufacturing Raw material Products

The manufacturing Process Materials Science, Statics, Dynamics, Thermodynamics, Fluid dynamics Products Material Transformation Processes Assembly Raw Material Machines and Automation

Manufacturing Process Overview SFF Finishing Assembly Powders Products Pressing Firing/ Sintering Injection Molding Blow molding Stamping Sheet metal forming Raw Material Continuous Casting/Rolling Rolling Machining Forging/ Press forming Ingot casting Extruding Molten Material Casting Shapes Single crystal pulling Special Increasing level of detail

Shapes and Production Method TABLE 1.2 Shapes and Some Common Methods of Production

HISTORY OF MANUFACTURING

History of Manufacturing (concluded) TABLE 1.1 Historical development of materials and manufacturing processes.

Engineering Materials FIGURE 1.4 An outline of engineering materials

Aluminum Automobile FIGURE 1.5 . (a) The Audi A8 automobile, an example of advanced materials construction; (b) The aluminum body structure, showing various components made by extrusion, sheet forming, and casting processes. Source: Courtesy of ALCOA, Inc.

Production Methods for a Simple Part FIGURE 1.6 Various methods of making a simple part: (a) casting or powder metallurgy, (b) forging or upsetting, (c) extrusion, (d) machining, (e) joining two pieces.

Machining of a Mold Cavity FIGURE 1.8 Machining a mold cavity for making sunglasses. (a) Computer model of the sunglasses as designed and viewed on the monitor. (b) Machining the die cavity using a computer numerical control milling machine. (c) Final product produced from the mold. Source: Courtesy Mastercam / CNC Software, Inc.

Fundamentals of manufacturing - Manufacturing Concepts The method chosen depends on the material and the shape and properties required Formability Machinability Hardenability Castability Compactability Sinterability Weldability

Why is Manufacturing Important? Impact on economy Major wealth creation engines Gross Domestic Product jobs Most decisions made during design are impacted by production/manufacturing processes Critical Decisions/Trade-offs function vs cost vs schedule Choose materials Choose process(es) Cost determined by the material and the processes used to create the shape

Big "M" - the Process Step Cost of a change Identify the requirements $0.1 Define one or more concepts, test them against requirements iterate downselect $1.00 Flesh the chosen few out (details) test them against requirements iterate down select $10.00 Final design test against requirements iterate $100.00 Plan for production select processes identify process steps define process parameters document Acquire material Produce $1000.00 Support

Design Steps FIGURE 1.2 (a) Chart showing varous steps involved in designing and manufacturing a product. Depending on the complexity of the product and the type of materials used, the time span between the original concept and the marketing of a product may range from a few months to many years. (b) Chart showing general product flow, from market analysis to selling the product, and depicting concurrent engineering. Source: After S. Pugh, Total Design. Addison-Wesley, 1991.

Some functional parameters affected by production processes Mechanical properties (Strength, Hardness, Fatique, Ductility, Resistance to environment) Tolerances Surface finish Resistance to corrosion and abrasion Electrical properties Thermal Properties Appearance/surface finish

Materials Vs Processes Source: Kalpakjian P 1225

Commercially Available Materials

Approximate Amount of Scrap Produced in Various Manufacturing Processes BUY to FLY RATIO

Advanced Materials Figure 40.1 Advanced materials used on the Lockheed C-5A transport aircraft. (FRP: fiber-reinforced plastic)

Material Changes From C-5A to C-5B Military Cargo Aircraft

Manufacturing Process Capabilities Figure 40.3 Manufacturing process capabilities for minimum part dimensions. Source: J. A. Schey, Introduction to Manufacturing Processes (2d ed.). McGraw-Hill, 1987.

Dimensional Tolerance Figure 40.4 Dimensional tolerance capabilities of various manufacturing processes.

Dimensional Tolerance and Surface Finish Figure 40.5 Relationship between relative manufacturing cost and dimensional tolerance. Figure 40.6 Relative production time, as a function of surface finish produced by various manufacturing processes. Source: American Machinist. See also Fig. 25.33.

Approximate Ranges of Machinery Base Prices

Examples of General Function/Process Relationships Cast metals tend to be brittle Forging adds strength along flow lines Machining is cost effective for small lot sizes Casting, forging and extrusion have high setup costs but low production costs Heat treatments affect hardness, strength, corrosion resistance and fatigue properties Machining results in lots of scrap (the buy to fly ratio)

Buy to Fly Ratio The weight of the purchased raw material divided by the weight of the final part Process Buy to fly ratio Machining 1.1 - 50 Hot closed die forging 1.2-1.5 Sheet metal forming 1.1-1.25 Extrusion 1.1-1.3 Permanent mold casting 1.0-1.2 Powder metallurgy 1.0-1.05

Critical Fact You cannot design any hardware without taking into account the production process used to make that product Manufacturing considerations must be included in the design as early as possible

What is Manufacturing - Dimensions Product Creative Characteristics (How new products differ from previous ones) Product Size (physical dimension) Product Complexity/Sophistication Scale Material Flow Degree of Automation Organization

Product Creative Characteristics How new products differ from previous ones Selection design (Lego houses) Configuration design (automobiles) Parametric design (portable generators) Redesign (New VCR) Original design (the original VCR, the Space Shuttle)

Product Size (physical dimension) A individual device on a computer chip A computer chip A television An automobile A Navy cruiser

Number of parts/amount of electronics/intelligence A nail A TV A car or truck A 777 aircraft A satellite Mars sojourner A CPU chip (5 million components)

Scale Number of people and disciplines involved Artisan Garage machine shop General Motors, Arlington Plant Boeing Commercial Aircraft Engineering firms who make bridges, chemical plants or dams

Material Flow How the work is organized on the shop floor Discrete parts (traditional job shop) Cellular (New machine shops) Semicontinuous Continuous flow (bottle making) Process (chemical industry and oil refineries)

Degree of Automation How much automation exists on the shop floor Manual Machine assisted Computer controlled - islands of automation Computer integrated manufacturing

Company Organization How the enterprises organize to produce Traditional Lean Agile Next Generation

Specific trends - Lean Manufacturing No waste of any kind Material waste No scrap - process right each time Work-in-Process Pull material flow (KANBAN system) Personnel waste Cross functional teams Design product so there is only one way to assemble product (poke-a-yoke) Time Waste Concurrency in operations where possible

Flexible manufacturing The ability to manufacturing multiple products on a single line

Agile Manufacturing The ability to thrive and prosper in an environment of constant and unanticipated change Agile Manufacturers must be able to change their business processes in hours to weeks to satisfy new and short lived customer demands Design cycle times reduced ten fold Production process changes in minutes

Agile, lean and flexible Manufacturing Lean + Flexible = Agile Some Lean and Flexible proponents also claim agility The name is not important - The trends identified are

Summing up Introduction Introductory overview of the larger issues Who am I? Statement of course goals Overall class schedule Statement of assumptions and policies Introductory overview of the larger issues Definitions - "Manufacturing vs manufacturing" Basic concepts The importance of Manufacturing Dimensions of Manufacturing Future trends in Manufacturing

Homework Read General Introduction and Part I in Kalpakjian Do Questions 1.22, 1.25, 2.32, 2.38, 4.32 in Kalpakjian These are review questions to test if you have met the prerequisites