2. Process Design
• Process design is concerned with overall sequence of
operations required to achieve the product
specifications
• It specifies the type of work stations, the machines
and equipments necessary ad the quantities in which
each is required
• Sequence of operations determined by
–
–
–
–
Nature of the product
Materials used
Quantities being produced, and
Existing physical layout of the plant
3. Process Design- Scope
• Design of manufacturing process starts with the
receipt of product specifications and ends with the
final plan for the manufacturing of the product
• Steps involved in process design are
– Careful review of product design and specifications to
ensure that economical manufacture is feasible
– Determination of the method of manufacture that will result
in the optimum manufacturing cost
– Selection or development and procurement of all machines,
tools, jigs and fixtures etc. required for manufacturing
product at the required quantity level/rate of production
4. Process Design
– Layout of the production area and auxiliary spaces and
installation of the manufacturing facilities
– Planning for and establishing the necessary control of
materials, machines and manpower to ensure effective
utilisation and economical; production of the product
5. Process Design- Basic Factors
• Basic factors affecting the design of manufacturing
process are
– Volume or quantity of the product to be manufactured
– The required quality of the product, and
– The equipment that is available or that can be procured for
the manufacture of the product
• Major factors affecting process design decisions
–
–
–
–
–
–
Nature of product/service demand
Degree of vertical integration
product./service and volume flexibility
Degree of automation
Level of product / service quality
Degree of customer contact
6. Process Design- Basic Factors
• Nature of product / service demand
– Production system has to be designed to produce products /
services of the kind the customer want, when they want and
at a cost that allows the firm to be profitable
– Production process to have adequate capacity to produce
the volume of products / services that customers want
• Degree of vertical integration
– Vertical integration is the amount of production and
distribution chain, from suppliers of raw materials and
components to the delivery of finished products to the
customers, that is brought under the ownership of a
company, whether towards the market or towards the
sources of supply
7. Process Design- Basic Factors
• Product/Service and volume flexibility
– Ability to respond fast to the customer’s needs is known as
flexibility
– Product/service flexibility
• Ability of production system to change from production of
one product/service to another
– Volume flexibility
• Ability to quickly increase or reduce the volume of
product/service produced
• Degree of automation
– Degree of automation to be adopted and integrated into the
production system is a key issue in process design, because
of the high cost involved in automation and also the difficulty
involved in integrating into the existing operations
8. Process Design- Basic Factors
• Level of product/ service quality
– Mass produced products with high product quality offer a
better competitive edge to the manufacturer
• Degree of customer contact
– In custom built product/services, the customer is the central
focus of the design of production processes
– In case of standardised products/services, the customer’s
interaction does not affect the design of production
processes in a big way
9. Types of Process Designs
• Basic type of production system and the finished
goods inventory policy to be used must be decided at
the earliest stages of process planning
• Common type of production systems are
– Product- focused production system
– Process-focused production system
– Group- technology / cellular manufacturing system
10. Product Layout
• Machines arranged in a line depending upon sequence of
operations
• Material moves in a line from the first machine to the
finished product on the last machine.
• Investment higher as compared to process layout
BETTER SUITED FOR STANDARDISED PRODUCTS
ON A MASS SCALE PRODUCTION. EX
CHEMICALS,PAPER
11. PRODUCTION SUB-SYSTEM
RAW MATERIALS
RECEIVING
OPERATION B
STORAGE
OPERATION A
MATERIAL FLOW
EDP
CONTROL
SYSTEMS
OPERATION D
OPERATION C
SHIPPING
FINISHED GOODS
INFORMATION
FLOWS
CONTINUOUS FLOW PRODUCTION SYSTEM (FLOW SHOP)
12. Process Layout
• Grouping together of similar machines in one
department
• Material moves from one group of machines to the
other
• Movement over longer distance and along criss-cross
paths
• May also involve part finished inventory waiting
BEST SUITED FOR INTERMITTENT TYPE OF
PRODUCTION/LIGHT AND HEAVY INDUSTRIES
13. PRODUCTION SUB-SYSTEM
RAW MATERIALS
RECEIVING
OPERATION A
WIP
MATERIAL FLOW
STORAGE
FINISHED
GOODS
EDP
CONTROL
SYSTEMS
WIP
OPERATION D
SHIPPING
FINISHED GOODS
OPERATION B
WIP
WIP
OPERATION C
INFORMATION
FLOWS
INTERMITTENT FLOW PRODUCTION SYSTEM (JOB SHOP )
14. Group Technology (GT)/ Cellular
Manufacturing (CM) systems
• A form of production that has been developed
recently
• In GT,the products or components being
manufactured are placed in families or groups and
separate manufacturing cells are used for
manufacturing these groups
– GT enables production of a wide variety of parts in small
batches to achieve economies of line-flow production without
product standardisation
• CM is a subset of GT concept
– A close grouping of equipments for processing a sequence
of operations in multiple units of a part or a family of
parts,called manufacturing cell
15. Group Technology (GT)/ Cellular
Manufacturing (CM) systems
– Use of cells reduces the distance moved by parts between
machines
– Transportation costs reduced as parts do not have to moved
in large batches
– Reduction in w-i-p inventory, and the manufacturing cycletime or through-put time
• Most common application in automobile spare parts
manufacturing
16. CELLULAR MANUFACTURING LAYOUT
CELL # 2
CELL # 1
1
2
1
3
5
2
4
PART B
1
2
4
PRODUCTION OPERATION
PART D
PART X
PART Y
1
PART A
3
CELL # 4
3
2
3
CELL # 3
PRODUCT OR MATERIAL FLOW
19. Combined Layout
• Combination of product & process layout with an
emphasis on either
• Generally adopted in industry
• In fabrication plants including assembly, fabrication
tends to employ process layout while assembly areas
employ product layout
– Soap manufacturing industry employs product line for
manufacturing of soap, but ancillaries such as heating,
manufacturing of glycerin, power house etc. Are arranged on
functional basis.
21. Process Technology
• Refers to the equipment, people and systems used to
produce a firm’s products and services
• Five types of process technologies are
– Job shop technology
• Suitable for a variety of custom-designed products in
small volume
– Batch technology
• Suitable for a variety of products in varying volumes
– Assembly line technology
• Suitable for a narrow range of standardised products in
high volumes
– Continuous flow technology
• Suitable for producing a continuous flow of products like
chemical plants, oil refineries
– Project technology
• Suitable for producing products that are tailor made to
the unique requirements of each customer
22. Process Technology Life Cycle
• Manufacturing cost per unit decreases in mature
products over a period of time
• Life cycle starts from the stage of ‘start up’ and ends
in the stage of ‘decline’
• Manufacturing process undergo a change from job
shop through batch production, assembly line
production and continuous flow production
• Output volumes ,rates of process innovation and
degree of automation also changes from the first
stage to the last stage
– Low at start-up and high during maturity stage
23. PRODUCT LIFE CYCLE AND PRODUCTIVE SYSTEM TYPES
PROCESS
FOCUSSED,
TO ORDER,
BATCH
PRODUCT
FOCUSSED,
TO STOCK,
BATCH
PRODUCT
FOCUSSED,
TO STOCK,
CONTINUOUS
STAGES OF DEVELOPMENT
DECLINE
MATURITY
GROWTH
INTRODUCTION
SALES VOLUME
PROCESS
FOCUSSED,
TO ORDER,
JOB SHOP
25. Process Selection/ Process
Design
• Process design is concerned with overall sequence of
operations required to achieve the product
specifications
• Selection of appropriate process technology affects
the economics of operation and hence needs to be
done considering various associated aspects
26. References
• Production & Operations Management:
Aswathappa / Bhat
• Production and Operations Management:
Chunnawalla/Patel
• Modern Production / Operations
Management: Buffa / Sarin
• Operations Management: R.G.Schroeder
29. PRODUCT- PROCESS MATRIX
LOW VOLPRODUCT CYCLE
LOW
STANDARDISA
TION, ONE OF
A KIND
HIGHER VOLFEW MAJOR
PRODUCTS
NONE
JOB SHOP
PROCESS LINE
JOB SHOPBATCH
PROCESS
ASSEMBLY
LINE
CONTINUOUS /
FLOW SHOP
LOW VOLMULTIPLE
PRODUCTS
HIGHER VOL-HIGH
STANDARDISATION
,COMMODITY
PRODUCTS
NONE
30. Process alternatives- Decision
• Depends upon various factors
– Batch size and Product variety
– Capital requirement
– Economic analysis
• Batch size and Product variety
–
–
–
–
For a single product having a large demand
Product focused organisation dedicated to the single product
Gives low production cost per unit
System very inflexible
• Equipments specialised to the product and employees
specifically trained make it impossible to change the
system to produce any other product
31. Process alternatives- Decision
• Product-focused batch system appropriate when
number of product design increases and batch size of
the products decrease
– System relatively inflexible but possible with some difficulty
to change the equipments and employees for other products
• Job shop producing unique products in batches of a
single item appropriate for production of many oneof-a kind products
– System has highest flexibility
• Cellular manufacturing of some of the production
parts within a job shop becomes appropriate when
the number products decreases and batch size of
products increases as compared to the previous case
32. Process alternatives- Decision
• Capital requirements
– Capital required for the production system depends upon on
the type of production processing organisation
– Requirement maximum for product focused, dedicated
systems and diminishes for product focused batch systems
and cellular systems
– Requirement minimum for process focused job shop
production systems
• Economic analysis of Production process
– As fixed and variable costs tend to differ from one form of
production process to another, economic analysis used for
comparing alternative processing plans for the production of
products
– Cost function of processing alternatives, the concept of
operating leverage, break-even analysis and financial
analysis are important aspects of economic analysis
33. Process Design/Selection
• Process selection is a major strategic decision as it
involves allocation of resources of a long nature
• The transformation process is expected to generate
an output desired by the market and should be done
in the most cost efficient way
• Process selection has a business dimension
– To get into the market and stay there, and once this is done
– To win orders
