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