product design and process selection

Unit 2

Product design and Process Selection

What is a product?

• Product is anything that can be offered to the market that can satisfy a want or need.

• There are 2 concepts for a product- narrow concept and wide concept

• That is why it is defined as a bundle of utilities• Typology of the product may be divided into 2

namely---• Tangible and intangible

• Design is the conversion of ideas and concepts into a physical form

• Design means the determination of shape, pattern, size, the functional aspect etc of the product which is offered to the customer in the form of the output of the company

• “Product design in its broadest sense includes the whole development of the product through all preliminary stages until the actual manufacturing begins”--- C.S.Deverell

Product design

What is a design?

• Reverse engineering is the process of carefully dismantling the competitors product to understand its unique features and concepts

• Manufacturability – designing a product in a such a way that its assembling is done easily; type of machines, skilled workers etc. are considered.

Elements in product designR&D

Reverse Engineering

Manufacturability

Standardization

Modular design

Robust Design

Concurrent Engineering

CAD

PLC

• Modular design: is another type of standardization where the product is designed in parts or modules. Each module will become the sub assembly of another product

• Robust design: means designing a product that is operational in varying environmental conditions.

• Eg:- Jeep & Car• Concurrent engineering is the involvement of

members from all the departments in the product designing; saves time compared to sequential approach.

Objectives of product design

• To create attention in product for increasing its sales potential

• To enlarge the importance of the product from customers point of view

• To make the product more effective and create more utility

• To produce better quality at lowest cost

• The factors influencing the product design are based on two perspectives- customer and the organisation

Factors influencing product design

Customer’s perspective

Functions

Aesthetics

User friendlyEsteem

associated with

possession

Organisation’s Perspective

Cost of material

Cost of labour

Replacement, exchange,disposal

• Function properly• Reliability• Easy to operate• Accessibility of

servicing• Ruggedness• Appearance• Space utilisation

Requirements of a good product design

• Easy to manufacture• Utilisation of the

available resources• Use of standard

components where ever possible

• Minimum number of parts• Minimum number of

operations• Easy to pack and

distribute

In order to achieve customer

satisfaction

Making adequate profit

means

Issues in product design

• Product liability • Intellectual property which is the property of the

mind or the intellect is legally protected which a designer has to keep in mind

• Product design and customer• Protection of intellectual property

• Exposure to undesirable ( Internet)• Advertising of designs (Coke)

• Testing of the design( Human testing)

– Global warming, deforestation, pollution, waste management,

Legal issues

Ethical issues

Environmental Issues

• It is that part of the organisation that transforms input into output

• The objective of the process is to provide maximum overall value to the customer

• It is concerned with the sequence of activities or operations required to achieve the product specification

• It is the complete definition and description of the steps in the production process and the linkage between different steps

Process design

Process

Process Design

• In this type of production system, the production department is organized according to the type of product or service being produced

• All the production operations required to produce one product is grouped into one production department/work centre

• The flow of the item being processed is dictated by individual product requirements, so the routes through the system are variable.

• It is also called Line flow production/ Continuous production

Types of process design

Product focused system


Process focused system

• It is the system where production operation are grouped according to the type of process

• All production operations having similar technological processes are grouped together to form the production department.

• The individual processes are arranged in a sequence so that the entire system is integrated for a single purpose like one giant machine

• The nature of demand determines the demand on the production system and each component flows from one process to the other intermittently


Repetitive focus system

• It is the type of focus that falls between the product and the process systems

• Repetitive focus works on modules which are components previously produced through continuous process like spares of automobiles

• These modules are used for customizing the product thereby getting the economic advantage of continuous model and the custom advantage of process model like high variety, low volume

• Eg: Automobiles, fast food chains etc

• Rapid low cost production of goods & services that fulfill increasingly unique customer desire.

• Products are customized for individual customers or for niche markets.

• 4 Approaches to Mass Customization:-

Mass Customization Focus

Repeat again (Transparent

Customization)

Either – Or(Collaborative Customization)

Sort-through(Adaptive

Customization)

Form – Of(Cosmetic

Customization)

Product

No change

Change

Representation

No Chang

e

Change

• Machines are grouped into cells & cells function like a product layout within a large process layout.

Cellular Manufacturing / Group Technology System

Process Selection

• Process selection refers to the way an organisation chooses to produce its goods and services

• It takes into account the selection of technology, capacity planning, layout of facilities etc

• The organisations decision on process selection will be based on strategies like make or buy, capital intensity and flexibility

• Process by market orientation– Make to stock– Make to order– Assemble to order

• Process based on production system like flow or intermittent

• Process and customer involvement– Self service like department stores– Customized Product selection as in cars

Process categorization

• A common way of defining a product is by drawing or creating its blue print.

• Assembly drawing helps to find out what are the individual components and what is their inter relationship.

• Detailed engineering drawings help the in-house persons and purchasing agents with the technicalities in the components for producing/purchasing.

• A parts list is then made which give in specifications of the parts like, name, number, dimension etc.

• Drawings and parts list together will determine the machines & materials

PROCESS SELECTION

Process Selection process

Assembly Drawing and parts list

• Design document – engineering drawings, parts list

• Material specification – material type, grade, properties

• Manufacturing data – surface finish, tolerances, special treatments

• Geometry – shape, size, weight, features

• Material evaluation – shape, properties

• Critical processing factors – correlate data

Design document

Material specificati

on

Geometry

Manufacturing data

Material evaluatio

nCritical

Processing Data

Process Selection

table&identify suitable processSequence process

Further processi

ng

req?

• Layout refers to the arrangement of facilities.

• A plant layout refers to the arrangement of machinery, equipments and other facilities like the shipping departments, tool rooms, maintenance rooms, employee amenities and so on for the quickest and smoothest production at the least cost

Layout decision

Meaning- Layout

Principles of plant layout

Maximum Security

Coordination

Use of Volume

Visibility

Accessible for maintenance

Minimum Distance

Minimum Discomfort

Flexibility

Efficient Process Flow

Minimum Handling

Providing workers own space

Inherent Safety

Layout decision

Importance- Layout

• Economies of handling• Minimization of production delays• Minimum equipment investment• Better production control• Effective usage of available area• Avoidance of bottle necks• Better supervision• Avoidance of unnecessary and costly

changes

• Also called straight line layout/ line layout is the method in which machines are arranged in one line depending on the sequence of operations

• Materials are fed into one machine and the output comes out of the last machine

• In between partly finished goods travel automatically from one machine to another, the output of one becomes the input of another

Types of layout

Product layout

• Regulation of production as it is planned in a sequence

• Scientific material handling

• No bottlenecks in the production

• Prompt production• Low W-I-P• Lesser supervision• Greater possibility

of space utilisation

Product layout

• Heavy capital investment

• Heavy overhead charges

• Demerits of breakdown

• Inflexibility• Lack of availability

of specialised supervisors

Advantages Disadvantages

• Also called functional layout/ Job layout is the method in which machines are arranged on a functional basis and the operations of the same type are performed in the same area.

• This type of layout is used where – Expensive machinery is needed– Production involves a large variety of items– Operations are not balanced in time– The demand is small and intermittent

Types of layout

Process layout

Process layout


• Lower capital investment

• Greater flexibility• Specialisation• Effective

supervision• No disruption in

work schedules• Low overhead

costs

• Complexity of production planning

• Difficulty of material handling

• Greater floor area• Large stock of

materials in process

• Longer processing time

• It is the layout in which the material or major component remains stationary and men, machinery and tools are brought to the location

• This is especially suitable for products that are bulky and heavy like ships, aircrafts, locomotives, building etc

• Its advantages are– Men and machines can be used for a wide

variety of operations– The investment in layout is small– The high cost and difficulty in transporting the

bulk product can be avoided• Disadvantages are

– There involves a low content of work in progress– It involves high equipment handling cost

Types of layout

Fixed Position layout

Types of layout

Cellular Manufacturing/ Group Technology layout

• In this layout, machines are grouped into cells and the cells function somewhat like a product layout

• Cellular Manufacturing /Group Technology, seeks to take full advantage of the similarity between parts, through standardization and common processing

• Cellular Manufacturing systems machines are grouped together according to the families of parts produced.

Types of layout

Cellular Manufacturing/ Group Technology layout

• The major advantage is that material flow is significantly improved, which reduces the distance travelled by materials, inventory and cumulative lead times.

• Cellular Manufacturing employs setup reduction and gives the workers the tools to be multi process, operating multiple processes, and multifunctional, owning quality improvements, waste reduction, and simple machine maintenance.

• This allows workers to easily self-balance within the cell while reducing lead times, resulting in the ability for companies to manufacture high quality products at a low cost, on time, and in a flexible way

Lean Manufacturing System

Meaning of Lean Production

• The term lean defines a system that utilizes less, in terms of all inputs, to create the same output as the mass production while contributing more to the customers

• The basic idea behind Lean is the abolition on “Muda” (Waste), Cost reduction and Employee empowerment

• It has enabled the companies to gain in productivity, which results in customer satisfaction through superior quality and prompt delivery

• The under lying concept is to make problems visible, when and where they occur and take corrective measures to prevent recurrence


Steps in Lean Production

There are 5 essential steps in Lean

• Identify value: value is related to how the specific product meets the customers requirements at a specified price and time– Identifying the features that create value to the

customers is the first step

• Identify the value stream: which is identifying the activities that contribute to value– Necessary activities are defined as prerequisite

and others are reduced or avoided


Steps in Lean Production• Improve Flow: flow is the uninterrupted movement

of product through the system to the consumer– Major hurdles/buffers for the smooth flow are

work in queue, batch process and transportation – Streamlining them will help in smooth flow

• Allow customer pull: which is to make the process responsive to providing the product or service only when the customer needs it- not before or after

• Work towards perfection: which means to continue the above steps to remove waste, improve flow thereby improving quality– When the product spends less time in process,

damages or obsolescence is reduced– Simplification of processes reduces variation


Advantages of Lean Production

• Reducing the manufacturing time• Helps to reduce the floor space• Helps to increase manufacturing

productivity• Helps to boost profits• Helps to achieve good customer

relations• Cultures are standardized


Lean Production- Tools and techniques

• Cellular Manufacturing: cell consists of equipment & workstations arranged in order to maintain smooth flow of materials; assigned with skilled, qualified workers.

• Kaizen( Continuous Improvement): is a concept whereby organisations undergo a systematic, gradual, orderly and continuous endeavor for improvement– Improvement may take place in the form of reduced

inventory, cycle time, defective parts, thereby increased productivity and profit

• Just in time: is the concept that attempts to eliminate the sources of waste by putting the right part at the right time at the right place– It tries to eliminate the waste due to WIP inventory, defects

and poor scheduling of the parts delivered– Customer demand is the driving force– It helps the internal processes of the company to meet

sudden changes in the demand



• 5S system: which details the actions required in the organisation and housekeeping of the work areas through 5 S’s which are:– Seiri (SORT): what is not needed, using a red tag system to

identify items that are not needed– Seiton(STRAIGHTEN/Set in order): what must be kept or

making things visible. “A place for everything and everything in its place”. It focuses on effective storage methods

– Seiso(SCRUB/ Shine): which focuses on keeping the work place clean and clutter free by taking care of the facility• Proper Ventilation ,air, leakages of oil, coolant,

contamination, breakage, misalignments etc are checked

– Seiketsu(Standardize): which is to standardize the work practice which can be followed by all. • Focuses on employee participation in work

improvement– Shitsuke(SPREAD/Sustain): focuses on defining a new

status quo and standard of work place• Through employee training and time to improve their

area



• Heijunka( Production smoothing): is a concept which focuses on keeping the production cost to the minimum by keeping the production level constant– It is one of the important concept adopted from Toyota

Production system which says that manufacture only what can be sold

• Standardization of work: means that each job is organized and is carried out in an effective manner.– No matter who does the job, the same quality should be

achieved– Standardization includes time needed to finish the job, the

steps in the job and the parts in hand– It aims in reducing WIP inventory, non value added activity

and achieving proper line balancing– A tool used for standardizing work is the “Takt time” which

refers to how often the parts are to be produced based on actual demand

Takt time= Available work time per day/ Customer demand per day



• Total productive maintenance: is a tool which is necessary to account for machine breakdowns which is a serious concern in manufacturing– There are 3 main components namely:– Preventive maintenance: which is to do with regular

maintenance on all equipments which leads to improvement in through put of each machine

– Corrective maintenance: which deals with decision as to fix or replace an equipments which is always breaking down

– Maintenance prevention: which is to buy the right machine which is easy to maintain on a regular basis

• Quality Function Deployment: is the concept of transforming the voice of the customer into the product – It is also called House of Quality where the output is

identified as required by the customer – It is identified and traced back to the input by making

changes in the product design and manufacturing process

Agile Manufacturing System

Meaning• AMS is a manufacturing system which has the ability to manage market changes as a matter of routine

• Market changes refer not only to production volume but also to product characteristics

• AMS is the ability to produce with in shortest lead time, low cost, high quality, customized products in various volumes

• A measure of agility is the time required to switch from one set of characteristics to another

• The aim of AMS is to combine organisations, people, technology into a single structure to manage quickly and at low cost infinite number of demand types

Agile Manufacturing System

Characteristi

cs• Greater Product customization at low cost• Quick response to changing market conditions• Upgradable products- designed for modularity,

recyclability, reconfigurability• Dynamic configuration of processes and systems to

accommodate swift changes


• Greater competitive advantage

• Innovative designs based on customers demands

• Responds quickly to crisis

• Flexibility in production

• High investment required in machinery and work force

• Sudden increase or decrease in demand may affect production leading to over or under stock

• Continuous updating required

Computer

integrated manufacturing

• It is the automated version of manufacturing process, where the three major manufacturing function - product and process design, planning and control and manufacturing process itself are done by automated technologies

• They are also known by the names of total factory automation/ animation, factory of the future etc

• The objectives of CIM are – Responsiveness to rapid changes in demand and

product modification– Better use of resources and reduction in inventory– Better control of production cost– Manufacturing of high quality at low cost

• Issues in CIM are related to the integration of technology with the processes as it is time consuming, data integrity as machines react clumsily to wrong data, extensive logic as there is no substitute for human mind

Computer

integrated manufacturing

• CAD is the use of computer systems in assisting the creation, modification, analysis and optimization of design

• It consists of the hardware and software required to perform the specialised function required by the particular firm

• The elements of CAD consists of – The human factor who is the designer or the engineer with

out whom the CAD system will not be successful– System factor which consist of hardware components

namely Cad work station, Input and output devices etc– Computer aided synthesis is the design process which can

tell you how to improve the design. The synthesis process gives many options to the design from which the most optimum and profitable can be chosen

• The advantages of CAD are namely Quality improvement, better computer- human interaction, flexibility and economy, reduced cost of product development

Computer aided designing (CAD)

Production and operation technology

• Machine technology• Process control is the use of information

technology to monitor and control a physical process– It is used for measuring thickness of paper or

control room temperature in refineries or heavy boiling plants etc

– It operates in a number of ways like• The sensors collect the data, which is read by

reading devices in periodic interval and are converted into digital signals which are transmitted to a computer which analyses the data and gives the output in various forms like warning lights, messages on computer consoles or printers

• Vision systems combine video cameras and computer technology and are often used in inspection roles. They are consistently accurate, do not get bored and are of modest cost

Production and operation technology

• Robots: is a machine which has the ability to hold, move and perhaps grab the items. They are effectively used to perform tasks that are monotonous and especially dangerous and those that can be improved by substituting machine with human especially when related to consistency, accuracy and speed– Eg: Welding of cars in car factories

• Automated storage and retrieval system ASRS: where it is extremely difficult to handle warehouses ASRS has been used. It is a mechanism which provides automatic placement and withdrawal of parts or products from and to the designated place in the warehouse– Eg: ASRS systems used in Walmart, Tupperware etc

• Automated guided vehicles(AGS) are electronically guided vehicles that are used to move parts and equipments

• It is the process of arranging the production line so that there is even flow of production from one work station to another without any delays and with least idle time

• The procedure for assembly line balancing may consist of:– Determining the tasks to be completed and Drawing

a Precedence diagram– Estimate the task time– Determine the cycle time– Balancing the assembly line

• Methods of assembly line balancing are :– Heuristic method which means to “find out by

experimentation”. They break down complex problems into simple manageable sub problems and solutions are found for each

Assembly line balancing

Education

product design and process selection