Manufacturing Engineering and Technology

Rapid Prototyping

Allows designers to generate parts quickly, directly from 3D models, for mockup and testing.

Discrete Products

Finished and sold as items, nothing is added (gears/bolts/nuts)

Concurrent Engineering

Also called simultaneous engineering. Cross functional teamwork in new product development projects that provides product design, quality engineering, and manufacturing process engineering all at the same time.

Manufacturing

The process in which raw material are changed into a finished project.

Continuous Products

Can be turned into something else or sold as it is (pvc/wire)

Steps for Finished Product

* Idea
* Prototype
* Testing
* Manufacturing

Careers involved in Product Development

* Engineering
* Designers
* Marketing
* Machining

First Production of Steel

Asia 600-800 A.D.

Ironmaking’s Beginning

Middle East about 1100 B.C.

First Industrial Revolution

* Began in England in the 1750s till 1851.


* Before it, goods were produced and batches required much reliance on manual labor in all phases of production.
* Centered around three new developments
* Coal-powered steam engine
* Textile machines
* Blast furnaces to produce iron

Second Industrial Revolution

Began in the mid-1900s with the development of solid-state electronic devices and computers

Mechanization

Began in England and other countries of Europe, basically with the development of textile machinery and machine tools for cutting metal; Soon moved to the U.S. where it continued to be further developed.

Interchangeable Parts

* Design, production, and usage of them was a major advance in manufacturing
* Early 1800s
* Conceived by American Manufacturer and inventor Eli Whitney
* Prior to Interchangeable Parts, no two parts could be made exactly alike (much hand fitting necessary)

Product Design

* Involves the creative and systematic prescription of the shape and characteristics of an artifact of achieve specified objectives while simultaneously satisfying several constraints
* 80% of the cost of product development and manufacture is determined by decisions made in the initial stages of design

What is essential for a successful product design?

* Innovative approaches
* Clearly specified functions
* Clear statement of performance expected
* Defined market and anticipated use(s)

Sequential Design (Traditional)

* Wasteful of resources and time
* Changes at material specification stage will necessitate a repeat of the Design Analysis Stage and subsequent stages

Life Cycle

In concurrent engineering, a view toward optimizing all elements involved in the life cycle of the product. Consists of four stages:

* Product start-up
* Rapid growth of the product in the marketplace
* Product maturity
* Decline

Life-Cycle Engineering

Requires that the entire life of a product be considered, beginning with the design stage and on through production, distribution, product use, and finally, recycling or disposal of the product

Paperless Design

No prototypes or mock-ups are built and construction and assembly is done directly from CAD/CAM software

Computer-aided Manufacturing

Involves all phases of manufacturing, by utilizing and processing the large amount of information on materials and processes gathered and stored in the organization’s database

Prototype

Physical model of an individual component or product

Virtual Prototyping

Software-based method that uses advanced graphics and virtual-reality environments to allow designers to view and examine a part in detail (AKA simulation-based design)

Design for Manufacture (DFM)

Comprehensive approach to integrating the design process with production methods, materials, process planning, assembly, testing, and quality assurance.

DFM requirements

* Fundamental understanding of the characteristics, capabilities, and limitations of materials, manufacturing processes, machinery, equipment, and tooling
* Variability in machine performance, dimensional accuracy and surface finish of the workpiece, processing time, and the effect of processing methods on product quality

DFA, DFMA, and DFD

* Design for Assembly
* Design for Manufacture and Assembly
* Design for Disassembly

Assembly

* Important phase of manufacturing and requires a consideration of the ease, speed, and cost of putting together the numerous individual components of a product
* Assembly costs can be substantial, typically ranging from 20-60% of the total product cost

Design for Service

Design should take into account the concept that, for ease of access, components that are most likely to be in need of servicing be placed, as much as possible, at the outer layers of the product.

Discarding

Implies that the products have reached the end of their useful life; does not necessarily mean that they are wasted and dumped into landfills.

Carbon Footprint

Quantifies the amount of greenhouse gases produced in our daily activities

Design For the Environment (DFE)

* Also called environmentally conscious design and manufacturing
* This approach considers all possible adverse environmental impacts of materials, processes, operations, and products, so they can be all taken into account at the earliest stages of design and production.

Design For Recycling (DFR)

Recycling may involve one of two basic activities:

* Biological cycle
* Industrial cycle

Cradle-to-cradle Production (C2C)

Considers the impact of each stage of a product’s life cycle, from the time natural resources are mined and processed into raw materials, through each stage of the manufacturing products, their use and, finally, recycling.

General Types of Materials Used

* Ferrous metals


* Nonferrous metals
* Plastics (polymers)
* Ceramics, glasses, glass ceramics, graphite, diamond, and diamondlike materials
* Composite materials
* Nanomaterials
* Shape-memory alloys, amorphous alloys, semiconductors, and super conductors

Mechanical Properties of Interest in Manufacturing

Strength, ductility, hardness, roughness, elasticity, fatigue, and creep resistance

Physical Properties of Interest in Manufacturing

Density, specific heat, thermal expansion and conductivity, melting point, and electrical and magnetic properties

Chemical Properties of Interest in Manufacturing

* Oxidation, corrosion, degradation, toxicity, and flammability
* Play a significant role under both hostile (such as corrosive) and normal environments

Manufacturing Properties

Indicate whether a particular material can be cast, formed, machined, joined, and heat treated with relative ease

Appearance

Includes characteristics as color, surface texture, and feel, all of which can play a significant role in a product’s acceptance by the public.

Availability

The economic aspect of material selection is as important as technological considerations. Thus, the availability of materials is a major concern in manufacturing. Furthermore, if materials are not available in the desired quantities, shapes, dimensions, and surface texture, substitute materials or additional processing of a particular material may well be required, all of which can contribute significantly to product cost.

Reliability of Supply

Important in order to meet production schedules and considering the fact that most countries import numerous raw materials.

Geopolitics

The study of the influence of a nation’s physical geography on its foreign policy

What factors lead to a shortened service life of a product?

* Improper selection of materials
* Improper selection of production methods
* Insufficient control of processing variables
* Defective parts or manufacturing-induced defects
* Poor maintenance
* Improper use of the product

A product is considered to have failed when it…

* Stops functioning
* Does not function properly or perform to specs
* Becomes unreliable or unsafe for further use

Failure of a product may be a result of…

* Design deficiencies
* Improper material selection
* Incompatibility of materials in contact (friction, corrosion)
* Defects in raw materials
* Defects induced during manufacturing
* Improper component assembly
* Improper product use

Manufacturing Processes

* Casting
* Forming and shaping
* Machining
* Joining
* Finishing
* Microfabrication and nanofabrication

What is the difference between Net-shape and Near-net-shape manufacturing? What is the benefits?

It is a matter of degree of how close the product is to its final dimensional characteristics. The benefits from not having to have additional operations performed to arrive at a finished product.

General types of production, in increasing order of annual quantities produced:

* Job shops (<100)
* Small-batch production (10-100)
* Batch production (100-5000)
* Mass production (generally over 100,000)

Computer-Integrated Manufacturing (CIM)

Integrates the software and hardware needed for computer graphics, computer-aided modeling, and computer aided design and manufacturing activities, from initial product concept through its production and distribution in the marketplace.

What tasks does CIM make possible?

* Responsiveness to rapid changes in product design modifications and to varying market demands
* Better use of materials, machinery, and personnel
* Reduction in inventory
* Better control of production and management of the total manufacturing operation

Various elements in CIM

* Computer Numeric Control (CNC)
* Adaptive Control (AC)
* Industrial Robots
* Automated materials handling
* Automated assembly systems
* Computer-Aided Process Planning (CAPP)
* Group Technology (GT)
* Just-In-Time production (GT)
* Cellular Manufacturing (CM)
* Flexible Manufacturing Systems (FMS)
* Expert Systems (ES)
* Artificial intelligence (AI)
* Artificial Neural Networks (ANN)

Why is product quality one of the most critical aspects of manufacturing?

Because it directly influences customer satisfaction, thus playing a crucial role in determining a product’s success in a global marketplace. Quality must be built into the product from its initial design through all subsequent stages of manufacture and assembly.

Why is continuous control of processes (online monitoring) a critical factor in maintaining product quality?

The objective is to control processes not the products. A machine for example may perform different once it has warmed up, affecting the products it produces.

Quality Assurance and Total Quality Management (TQM)

Widely recognized as being the responsibility of everyone involved in the design and manufacture of products and their components.

Product integrity is a term generally use to define the degree to which a product:

* Functions reliably during its life expectancy
* Is suitable for its intended purposes
* Can be maintained with relative ease

W.E. Deming, J.M. Juran, and G. Taguchi all emphasized the importance of management’s commitment to…

* Product quality
* Pride of workmanship at all levels of production
* the necessity of using Statistical Process Control (SPC) and control charts
* Importance of online monitoring and rapidly identifying the sources of quality problems in production, before even another defective part is produced

What is the major goal of process control?

To prevent defective parts from ever being made, rather than to inspect, detect, and reject defective parts after they have been made.

Standard Deviation

The level of defects are identified by this term. Denoted by the symbol sigma -six sigma is 3.4 defective per million parts made

Experimental Design

A technique in which the factors involved in a manufacturing process and their interactions are studied simultaneously. For example, variables affecting dimensional accuracy or surface finish in a machining operation can be identified readily, making it possible for appropriate preventative on-time actions to be taken.

Ergonomics

The study of how a workplace and the machinery and equipment in it can best be designed for comfort, safety, efficiency, and productivity.

Product Liability

Someone who is injured from a product’s unsafe or defective condition may recover damages. Manufactures, sellers, and suppliers may be held responsible.

Lean Production

A methodology that involves a thorough assessment of each activity of a company, with the basic purpose of minimizing waste at all levels and calling for elimination of unnecessary operations that do not provide any added value to the product being made. Also called lean manufacturing optimizes the processes used in order to maximize added value.

What does Lean Production focus on?

* Efficiency and effectiveness of each and every manufacturing operation
* Efficiency of the machinery and equipment used
* Activities of the personnel involved in each operation

Agile Manufacturing

The principle behind agile manufacturing is ensuring agility--and hence flexibility-- in the manufacturing enterprise, so that it can respond rapidly and effectively to changes in product demand and the needs of the customer.

Benchmark

Involves assessing the competitive position of other manufacturers with respect to one’s own position and setting realistic goals for the future. Becomes a reference point from which various measurements can be made and to which they can be prepared.

World-class Manufacturing

The demand for high quality products in an ever increasing global competition

The total cost of manufacturing a product generally consists of these components:

* Materials
* Tooling
* Fixed
* Capital
* Labor

Direct Labor

Also called productive labor, concerns the labor that is directly involved in manufacturing products.

Indirect Labor

Pertains to servicing of the total manufacturing operation; it is also called nonproductive labor or overhead.

Outsourcing

The purchase by a company of parts or labor from an outside source, either from another company or country, in order to reduce design and manufacturing costs

What are some problems with manufacturing abroad?

* Rising cost of shipping
* Social impact in political implications of any ensuing lower employment, especially in the European Union countries and the United States.