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Manufacturing Processes
An Introduction
By: Sunil Kumar Ojha
Do you ever heard Manufacturing ? Which is the leading Manufacturing
Country in the world? How Manufacturing affect economy
of acommon man and for a country ?
Curiosity How parts are made ????????
Introduction
Take a few moments and inspect some of the objects around you
Introduction
Introduction
What do they all have in common They have all been transformed
from raw materials Components of various size and
shape Assembled into the products you see
now
What is Manufacturing
Derived from 2 latin words Manus – hand Factus – make Made by hand
The process of converting raw materials into useful products.
What is Manufacturing Technologically
Manufacturing is the application of physical and chemical processes to alter the geometry, properties, and/or appearance of a given material to make parts or products
Includes assembly of multiple parts to make products
Typically carried out as a sequence of operations
What is Manufacturing
Economically Manufacturing is the transformation
of materials into items of greater value by means of one or more processing and/or assembly operations
Adds value
What is Manufacturing A nation’s level of manufacturing activity
is related directly to its economic health Generally, the higher the level of
manufacturing activity in a country, the higher the standard of living of its people
In the US, the manufacturing industries account for about 20% of the Gross National Product (GNP), 32 % in China and app. 15 % in India.
A Brief History of Manufacturing
Many manufacturing processes have been around for thousands of years
Can you name some ancient examples of the following: Grinding Forging / Smithy Work Casting Others
A Brief History of Manufacturing
Industrial Revolution (1760-1830) Change from agriculture/handicraft
economy to one based on industry and manufacturing Watt’s steam engine Machine tools Power spinning loom Factory system organization Interchangeable parts
A Brief History of Manufacturing
Interchangeable parts Pre-requisite for mass production Eli Whitney Contract to produce 10,000 muskets
for US government
A Brief History of Manufacturing
Second Industrial Revolution (late 1800s, early 1900s) Mass production Scientific management movement Assembly lines
Henry Ford Electrification of factories
1881 – first power generator in New York 1920 – electricity overtakes steam in
factories
Why Study Manufacturing? The costs of a product are substantially
determined in the product design phase As such, designers/engineering determine
up to 70% of the manufacturing costs Designers may make poor decisions about
materials, tolerances, shapes, size, and product function
All of these have tremendous impact on the processes used in the manufacturing of a product
Why Study Manufacturing? A thorough knowledge of
manufacturing processes is necessary for those who design and make the parts
If better decisions can be made in the early phases of product design Better products for customers Greater profits for manufacturing
companies
Manufacturing Example
You have been asked to design & produce paper clips (Developed by a Norwegian) (US Patent in 1901)
Let’s discuss important factors involved in the design and manufacture of paper clips
Manufacturing Example
What type of material would you choose to make this product?
Should it be metallic or nonmetallic? If metal, what type of metal? If “wire” shape, what diameter? Should it be round or other cross-
section? What should be the surface finish?
Manufacturing Example
How would you shape the wire into a paper clip? By hand on a simple fixture?
If not, what kind of machine would you design to make the paper clips?
How would you produce 10,000 clips? How about millions of clips?
Manufacturing Example
Clip must meet basic functional requirements Hold paper with sufficient clamping force Proper design – shape, size, feel,
appearance Stiffness and strength of material
Manufacturing Example
Too stiff Inconvenient for users
Not stiff enough Won’t hold papers
Yield stress too low Permanent deformation during normal
use
Manufacturing Example Can the wire undergo bending during
manufacturing without cracking or breaking? Is the wire corrosion resistant? Can the wire be easily cut without causing
excessive wear on the tooling? Will the cutting process produce a smooth
edge on end of wire? What’s the most economical method of
manufacturing the clip in the needed quantities?
Product Design Product design is a critical activity It has been estimated that 70-80% of
the cost of product development and manufacture is determined by decisions made in the initial design stages
The design of a product first request a thorough understanding of the functions and performance expected of the product
Product Design Traditionally design and manufacturing
activities have taken place sequentially
This practice has proven to be inefficient
Concurrent engineering was developed to find more effective ways to bring products to the market quicker
Products early to market enjoy higher profits and greater longevity
Product Design Concurrent engineering integrates the
design and manufacture of products, optimizing all elements involved in the product life cycle
Consists of several deliberate iterations All disciplines involved early in the
design stages so that the iterations Benefits to one automotive company
30% reduction in # of components 25% decrease in weight 50% decrease in manufacturing time
Design for Manufacturing
Design and manufacturing should never be viewed as separate activities
Components must be designed so that they meet design requirements AND can be manufactured economically
Design for Manufacturing DFM is a comprehensive approach to
the production of goods It integrates the design process with
materials, manufacturing methods, process planning, assembly, testing, and quality assurance
Requires designers have a fundamental understanding of the characteristics, capabilities, and limitations of materials, manufacturing processes, and equipment
Design for Manufacturing
Designers need to understand variability in: Machine performance Dimensional accuracy Surface finish Processing time Effect of processing method on
quality
Manufacturing Processes
Over 300 individual manufacturing processes have been identified in the industrial environment
Grouped into several families of processes sharing common characteristics
Manufacturing Processes Broad categories of processing
methods for materials include: Casting Forming and shaping Machining Joining Finishing Nanofabrication
Manufacturing Processes Casting
Expendable and permanent molds Forming and Shaping
Rolling, forging, extrusion, sheet forming, powder metallurgy
Machining Turning, boring, drilling, milling, planing,
shaping, broaching, grinding Chemical and electrical maching High-energy beam machining
Manufacturing Processes Joining
Welding, brazing, soldering, diffusion bonding, adhesive bonding, mechanical joining
Finishing Honing, lapping, polishing, deburring, surface
treating, coating, plating Nanofabrication
Nano = 1/billion Etching techniques, electron-beams, laser-
beams
Casting
Starting material is heated sufficiently to transform it into a liquid or highly plastic state
Casting process at left and casting product
Forming or Shaping
Starting workpart is shaped by application of forces that mareial plastically flow and get desired shape
Examples: (a) forging and (b) extrusion
Machining Process
Excess material removed in the form of chips with the help of cutting tool from the starting piece so what remains is the desired geometry
Examples: (a) turning, (b) drilling, and (c) milling
Joining Process
Two or more parts assembled together to make single part.
Two types:- Permanent : like welding, brazing,
adhesive bonding Non Permanent joining: Nut Bolt, Screw
etc
Finishing Lapping, Polishing Deburring Surface treating Coating Plating
Nanofabrication Nano = 1/billion Etching techniques, electron-beams, laser-beams
Manufacturing Processes Each manufacturing process has its
own advantages and limitations Selection of a particular
manufacturing process depends not only on the shape to be produced but on factors related to material properties For example, brittle materials cannot
easily be shaped or formed, but can be cast, machined or ground
Current Trends
Today engineering and manufacturing firms rely heavily on the use of CAD, CAE, and CAM techniques CAD – Computer Aided Design CAE – Computer Aided Engineering CAM – Computer Aided Manufacturing
Current Trends CAD
Visualization in Engineering Design CAE
Numerical Methods CAE Modeling & Digital Simulation Finite Element Analysis
CAM Manufacturing Processes CNC
Current Trends CIM – Computer Integrated Manufacturing
In simple terms, methodology where applicable engineering and manufacturing data is available to the entire business enterprise
Common CIM Technologies CNC – Computer Numerical Control Adaptive Control Industrial robots Automated handling of materials Automated and robotic assembly systems JIT – Just-in-Time production FMS – Flexible manufacturing systems Artificial intelligence
Current Trends
Benefits Better use of materials, equipment &
personnel Better control of production and
management of the total manufacturing operation
Greatly reduced duplicated information Responsiveness to rapid changes in
market High quality products at a lot cost
Quality Product quality is one of the most important
aspects of manufacturing Directly influences marketability of a product –
customer satisfaction Formerly – inspect products after they were made Currently – build quality in from the design stage
and subsequent to it Control of processes is a critical factor in product
quality – SPC (Statistical Process Control) Control the process, not the products Major goal is to prevent defects from occurring
rather than discover them after the fact
Quality TQM – Total quality management Quality assurance must be the
responsibility of everyone involved in design & manufacturing of a product
Pioneers in quality control 6 sigma - 99.999997%
Defects reduced to 3 per million