Introduction To Manufacturing Process PDF

©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  What is Manufacturing? “TAKE A FEW MOMENTS AND INSPECT VARIOUS OBJECT AROUND YOU…” “CAN YOU REALIZE THAT ALL THOSE OBJECTS HAD A DIFFERENT SHAPE...

©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  What is Manufacturing? “TAKE A FEW MOMENTS AND INSPECT VARIOUS OBJECT AROUND YOU…” “CAN YOU REALIZE THAT ALL THOSE OBJECTS HAD A DIFFERENT SHAPE?...” Some objects are made of a single part, but most objects are constructed by the assembly of a number parts made from variety of materials. ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  What is Manufacturing? The word manufacture is derived from two Latin words manus (hand) and factus (make); the combination means “made by hand”  “Made by hand” accurately described the fabrication methods that were used when the English word “manufacture” was first coined around 1567 A.D.  Most modern manufacturing operations are accomplished by mechanized and automated equipment that is supervised by human workers ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Manufacturing - Technologically Application of physical and chemical processes to alter the geometry, properties, and/or appearance of a starting material to make parts or products  Manufacturing also includes assembly  Almost always carried out as a sequence of operations Manufacturing adds value to the material by changing its shape or properties, or by combining it with other materials Figure 1.1 (a) Manufacturing as a technical process ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Manufacturing - Economically Important U.S. economy: % of Sector GNP Manufacturing 20% Manufacturing is Agriculture, minerals, etc. 5% one way by which nations create Construction & utilities 5% material wealth Service sector – retail, 70% transportation, banking, communication, education, and government ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Manufacturing Industries  Industry consists of enterprises and organizations that produce or supply goods and services  Industries can be classified as: 1. Primary industries - those that cultivate and exploit natural resources, e.g., farming, mining 2. Secondary industries - take the outputs of primary industries and convert them into consumer and capital goods - manufacturing is the principal activity 3. Tertiary industries - service sector ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Materials in Manufacturing Most engineering materials can be classified into one of three basic categories: 1. Metals 2. Ceramics 3. Polymers  Their chemistries are different  Their mechanical and physical properties are dissimilar  These differences affect the manufacturing processes that can be used to produce products from them ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  In Addition: Composites Nonhomogeneous mixtures of the other three basic types rather than a unique category Figure 1.3 Venn diagram of three basic material types plus composites ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Manufacturing Processes Two basic types: 1. Processing operations - transform a work material from one state of completion to a more advanced state  Operations that change the geometry, properties, or appearance of the starting material 2. Assembly operations - join two or more components to create a new entity ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e Figure 1.4 Classification of manufacturing processes ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e QUIZ B D E A C ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Processing Operations Alters a material’s shape, physical properties, or appearance in order to add value  Three categories of processing operations: 1. Shaping operations - alter the geometry of the starting work material 2. Property-enhancing operations - improve physical properties without changing shape 3. Surface processing operations - to clean, treat, coat, or deposit material on exterior surface of the work ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Shaping Processes – Four Categories 1. Solidification processes - starting material is a heated liquid or semifluid 2. Particulate processing - starting material consists of powders 3. Deformation processes - starting material is a ductile solid (commonly metal) 4. Material removal processes - starting material is a ductile or brittle solid ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Solidification Processes Starting material is heated sufficiently to transform it into a liquid or highly plastic state  Examples: metal casting, plastic molding Figure 1.5 ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Particulate Processing Starting materials are powders of metals or ceramics  Usually involves pressing and sintering, in which powders are first compressed and then heated to bond the individual particles Figure 1.6 ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Deformation Processes Starting workpart is shaped by application of forces that exceed the yield strength of the material  Examples: (a) forging, (b) extrusion Figure 1.7 ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Material Removal Processes Excess material removed from the starting piece so what remains is the desired geometry  Examples: machining such as turning, drilling, and milling; also grinding and nontraditional processes Figure 1.8 ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Waste in Shaping Processes Desirable to minimize waste in part shaping  Material removal processes are wasteful in unit operations, simply by the way they work  Most casting, molding, and particulate processing operations waste little material  Terminology for minimum waste processes:  Net shape processes - when most of the starting material is used and no subsequent machining is required  Near net shape processes - when minimum amount of machining is required ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Property-Enhancing Processes Performed to improve mechanical or physical properties of work material  Part shape is not altered, except unintentionally  Example: unintentional warping of a heat treated part  Examples:  Heat treatment of metals and glasses  Sintering of powdered metals and ceramics ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Surface Processing Operations  Cleaning - chemical and mechanical processes to remove dirt, oil, and other contaminants from the surface  Surface treatments - mechanical working such as sand blasting, and physical processes like diffusion  Coating and thin film deposition - coating exterior surface of the workpart ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e Can you ©2007 spot John Wiley theInc.hidden & Sons, M P Groover,face in the Fundamentals coffee of Modern beans? Manufacturing 3/e  Assembly Operations Two or more separate parts are joined to form a new entity  Types of assembly operations: 1. Joining processes – create a permanent joint  Welding, brazing, soldering, and adhesive bonding 2. Mechanical assembly – fastening by mechanical methods  Threaded fasteners (screws, bolts and nuts); press fitting, expansion fits ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Production Systems People, equipment, and procedures used for the combination of materials and processes that constitute a firm's manufacturing operations  A manufacturing firm must have systems and procedures to efficiently accomplish its type of production  Two categories of production systems:  Production facilities  Manufacturing support systems  Both categories include people (people make the systems work) ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Production Facilities The factory, production equipment, and material handling systems  Production facilities "touch" the product  Includes the way the equipment is arranged in the factory - the plant layout  Equipment usually organized into logical groupings, called manufacturing systems  Examples:  Automated production line  Machine cell consisting of an industrial robot and two machine tools ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Facilities versus Product Quantities A company designs its manufacturing systems and organizes its factories to serve the particular mission of each plant  Certain types of production facilities are recognized as the most appropriate for a given type of manufacturing: 1. Low production – 1 to 100 2. Medium production – 100 to 10,000 3. High production – 10,000 to >1,000,000  Different facilities are required for each of the three quantity ranges ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  P versus Q in Factory Operations Figure 1.2 P-Q Relationship ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Low Production Job shop is the term used for this type of production facility  A job shop makes low quantities of specialized and customized products  Products are typically complex, e.g., space capsules, prototype aircraft, special machinery  Equipment in a job shop is general purpose  Labor force is highly skilled  Designed for maximum flexibility ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Medium Production Two different types of facility, depending on product variety:  Batch production  Suited to hard product variety  Setups required between batches  Cellular manufacturing  Suited to soft product variety  Worker cells organized to process parts without setups between different part styles ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  High Production  Often referred to as mass production  High demand for product  Manufacturing system dedicated to the production of that product  Two categories of mass production: 1. Quantity production 2. Flow line production ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Quantity Production  Mass production of single parts on single machine or small numbers of machines  Typically involves standard machines equipped with special tooling  Equipment is dedicated full-time to the production of one part or product type  Typical layouts used in quantity production are process layout and cellular layout ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Flow Line Production  Multiple machines or workstations arranged in sequence, e.g., production lines  Product is complex  Requires multiple processing and/or assembly operations  Work units are physically moved through the sequence to complete the product  Workstations and equipment are designed specifically for the product to maximize efficiency ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e Types of production system Figure 1.9 ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Manufacturing Support Systems  A company must organize itself to design the processes and equipment, plan and control production, and satisfy product quality requirements  Accomplished by manufacturing support systems - people and procedures by which a company manages its production operations  Typical departments: 1. Manufacturing engineering 2. Production planning and control 3. Quality control ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Overview of Major Topics Figure 1.10 Overview of production system and major topics in Fundamentals of Modern Manufacturing. ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e A machining cell consisting of two horizontal machining centers supplied by an in-line pallet shuttle (photo courtesy of Cincinnati Milacron). ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e A robotic arm performs unloading and loading operation in a turning center using a dual gripper (photo courtesy of Cincinnati Milacron). ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Did you manage to spot the hidden person? ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e Dimensions and Tolerances Factors that determine the performance of a manufactured product, other than mechanical and physical properties, include :  Dimensions - linear or angular sizes of a component specified on the part drawing  Tolerances - allowable variations from the specified part dimensions that are permitted in manufacturing ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e Dimensions (ANSI Y14.5M-1982): A dimension is "a numerical value expressed in appropriate units of measure and indicated on a drawing and in other documents along with lines, symbols, and notes to define the size or geometric characteristic, or both, of a part or part feature" Dimensions on part drawings represent nominal or basic sizes of the part and its features The dimension indicates the part size desired by the designer, if the part could be made with no errors or variations in the fabrication process ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e Tolerances (ANSI Y14.5M-1982): A tolerance is "the total amount by which a specific dimension is permitted to vary. The tolerance is the difference between the maximum and minimum limits" Variations occur in any manufacturing process, which are manifested as variations in part size Tolerances are used to define the limits of the allowed variation ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e Bilateral Tolerance Variation is permitted in both positive and negative directions from the nominal dimension Possible for a bilateral tolerance to be unbalanced; for example, 2.500 +0.010, Figure 1.33 Ways to specify -0.005 tolerance limits for a nominal dimension of 2.500: (a) bilateral ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e Unilateral Tolerance Variation from the specified dimension is permitted in only one direction Either positive or negative, but not both Figure 1.33 Ways to specify tolerance limits for a nominal dimension of 2.500: (b) unilateral ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e Limit Dimensions Permissible variation in a part feature size consists of the maximum and minimum dimensions allowed Figure 1.33 - Ways to specify tolerance limits for a nominal dimension of 2.500: (c) limit dimensions ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e Tolerances and Manufacturing Processes Some manufacturing processes are inherently more accurate than others Examples:  Most machining processes are quite accurate, capable of tolerances = 0.05 mm ( 0.002 in.) or better  Sand castings are generally inaccurate, and tolerances of 10 to 20 times those used for machined parts must be specified ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  “Franklin Featherstone is sometimes referred to as the Father of Refrigerated Freight, because of his efforts in publicising the benefits of this form of transport “ How many “f” letter you counted in the sentence? ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Design & Manufacturing a Product: Defining a Product There are two general types of products: Physical Goods  Goods which are easily understood because the buyer can see and often experience their benefits prior to buying  Actions that companies offer to Services customers for the purpose of transaction ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Stage-Gate Product Development Process Idea Concept Idea Screening Development Generation Business Analysis Product Prototype Test Market Commercialization Design Development Management Management Management Review Review Review Once the decision to develop a new product is made, the actual product development process begins ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Characteristics of Successful Product Development Product quality  How good is the product resulting from the development effort? Product cost  What is the manufacturing cost of the product? Development time  How quickly did the team complete the product development effort? Development cost  How much did the firm have to spend to develop the product? Development capability  Are the team & the firm better able to develop future products as a result of their experience with a prod. dev. project? ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e Who design & develop products? Manufacturing Engineer Marketing Purchasing professional specialist Team leader Industrial Electronics designer designer Mechanical ©2007 John Wiley & Sons, Inc. designer M P Groover, Fundamentals of Modern Manufacturing 3/e  Design In general we can analyze design in four phases :-  Conceptual design  Detailed design  Manufacturing  Distribution, servicing, disposal etc What is the most important design phase? Which one of these stages effects the success of a new product? ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e  Importance of Design Stage 100 Life-cycle cost committed Product Life- Cycle Includes 80 Design Phase Total Cost (%) Cost incurred 60 Manufacturing Phase 40 Product usage phase Disposal phase 20 Ease of change 0 Conceptual Detailed Manufacturing Distribution, Design Design service, and Prototype disposal Design phase determines the most of the cost associate with delivering a product Typically, 80% of the cost of a product is fixed at the design©2007 stage John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e The Product Design Process Customer Requirements, Customer Needs Problem Identification Future Directions Preliminary Ideas Refinement Refinement Process Process NO Analysis and Criteria Decision Process Satisfied YES Implementation ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e Products in Various Stages of Life Cycle ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e Products in Various Stages of Life Cycle ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e ©2007 John Wiley & Sons, Inc. M P Groover, Fundamentals of Modern Manufacturing 3/e