PALANIVENDHAN MANUFACTUING SYSTEMS PFA GROUP TECHNOLOGY

1. Computer Aided Manufacturing
M.PALANIVENDHAN
Department of Automobile Engineering
SRM University, kattankulathur campus

2. Computer Aided Manufacturing
• What is Manufacturing
• It is the process of converting the raw material
into product.
• It encompasses
– Design of the product
– The selection of raw material
– The sequence of processes through which the
product will be manufactured.
Difference between production and manufacturing

3. Need of
Manufacturing
• Globalization
• International outsourcing
• Local outsourcing
• Contract manufacturing
• Quality expectation
• Operational efficiency

4. Manufacturing
Process
Starting material
(Raw material)
Machinery
Tools
Power
Labor
Completed part
(Product)
Scrap

5. Changes in manufacturing

6. Manufacturing engineers are required to achieve the
following objectives to be competitive in a global context.
• ‘edu tio i i e to
• Lo e the ost of the p odu t
• ‘edu e aste
• I p o e ualit
• I ease fle i ilit i a ufa tu i g to a hie e
immediate and rapid response to:
– Product changes
– Production changes
– Process change
– Equipment change
– Change of personnel

7. 7

8. Manufacturing systems approaches
• Automation (Low labor high prod.)
• Material handling technologies(scm)
• Manufacturing systems (integration of automated or manual )
• Flexible manufacturing (low volume and high mix product)
• Quality programs (6sigma)
• CIM (CAD CAM)
• Lean production (more work fewer resources)

9. Manufacturing System – Definition
• A set of operations performed on materials
which bring them closer to the desired final
form.

10. Production systems
• A production system is a collection of people,
equipment and procedures.
– Facilities (factory and the equipment)
– Manufacturing support systems(manage production
and to solve the technical and logistics problems
encountered in ordering materials)
blue collar workers, white collar workers

11. The Facilities
• Factory, production machine,tooling,material
handling equipment,inspection equipment,
computer systems
• Manual work systems
– Without aid of powered tools, only of hand tool
• Worker –machine systems
– (human worker +machine tool)
• Automated systems
– without participation of a human worker
– 1.semi automated 2. Fully automated

12. Manufacturing Support Systems
• To operate the production facilities efficiency to design the
processes and control the production and satisfy the product
quality

14. • Business Functions
– Comm to customer,sales,marketing
• Product Design
– Product development
• Manufacturing Planning
– Process planning, logistics issues, master
production schedule
• Manufacturing control
– Shop floor,inventory and quality control

15. Types of production
• Continuous process
• Mass production
• Batch production

16. Continuous Process
• In this type of industry, the
production process generally
follows a specific sequence.
• These industries can be easily
automated and computers are
widely used for process
monitoring, control and
optimization.
• Oil refineries, chemical plants,
food processing industries, etc
are examples of continuous
process industries.

17. Mass production
• Industries manufacturing
fasteners (nuts, bolts etc.),
integrated chips,
automobiles, entertainment
electronic products,
bicycles, bearings etc.
• which are all mass produced
can be classified as mass
production industries.
• Production lines are
specially designed and
optimized to ensure
automatic and cost effective
operation.

18. Batch Production
• The largest percentage of
manufacturing industries can
be classified as batch
production industries.
• The distinguishing features of
this type of manufacture are
the small to medium size of
the batch, and varieties of
such products to be taken up
in a single shop.
• Due to the variety of
components handled, work
centers should have broader
specifications.
• Another important fact is that
small batch size involves loss
of production time associated
with product changeover.

20. TYPES OF LAYOUT
• 1.FIXED POSITION LAYOUT
• 2.PROCESS LAYOUT
• 3.PRODUCT FLOW LAYOUT
• 4.GROUP TECHNOLOGY(CELLULAR) LAYOUT

21. 1.Fixed position
part” stationary
workstations move

22. 7/24/2014
• Fixed position layout
– Product must remain stationary throughout production
sequence
– Machines are brought to the product
– Higher expense due to robustness and accuracy of
equipment

23. 2.Process Layout
– organized by machine type

24. 3.Product flow layout
-Assembly/flow/transfer line

25. • Product flow layout
– Suited for high volume production
– Advantages: minimized material handling, easy to
automate material handling, less WIP, easier to
control
– Disadvantages: inefficient to alter the sequence of
operations, breakdown on one machine can stop
the entire line

26. What is Manufacturing
• It is the process of converting the raw material
into product.
• It encompasses
– Design of the product
– The selection of raw material
– The sequence of processes through which the
product will be manufactured.

27. Manufacturing can be defined as the
application of physical and chemical processes
to alter the geometry, properties, and/or
appearance of a given starting material to
make part or products

28. Manufacturing
Process
Starting material
(Raw material)
Machinery
Tools
Power
Labor
Completed part
(Product)
Scrap

29. Changes in manufacturing

30. Manufacturing engineers are required to achieve the
following objectives to be competitive in a global context.
• ‘edu tio i i e to
• Lo e the ost of the p odu t
• ‘edu e aste
• I p o e ualit
• I ease fle i ilit i a ufa tu i g to a hie e
immediate and rapid response to:
– Product changes
– Production changes
– Process change
– Equipment change
– Change of personnel

31. TYPES OF MANUFACTURING
• Continuous process
• Mass production
• Batch production

32. Continuous Process
• In this type of industry, the production process
generally follows a specific sequence.
• These industries can be easily automated and
computers are widely used for process
monitoring, control and optimization.
• Oil refineries, chemical plants, food processing
industries, etc are examples of continuous
process industries.

34. Mass production
• Industries manufacturing fasteners (nuts, bolts
etc.), integrated chips, automobiles,
entertainment electronic products, bicycles,
bearings etc.
• which are all mass produced can be classified as
mass production industries.
• Production lines are specially designed and
optimized to ensure automatic and cost effective
operation.
• Automation can be either fixed type or flexible.

36. Batch Production
• The largest percentage of manufacturing
industries can be classified as batch production
industries.
• The distinguishing features of this type of
manufacture are the small to medium size of the
batch, and varieties of such products to be taken
up in a single shop.
• Due to the variety of components handled, work
centers should have broader specifications.
• Another important fact is that small batch size
involves loss of production time associated with
product changeover.

38. Volume

39. Manufacturing systems
• Agile manufacturing
• Flexible manufacturing
• Just-in-time manufacturing
• Lean manufacturing
• Mass production
• Ownership
• Prefabrication
• Rapid manufacturing

40. CIM WHEEL

42. Current trends in manufacturing
• Group Technology
• Design for manufacturing
• Computer Aided Process Planning (CAPP)
• Total Quality Approach
• Concurrent engineering
• Rapid prototyping
• Computer Integrated manufacturing (CIM)
• Digital Manufacturing
• Green Manufacturing
• Lean Manufacturing
• Agile manufacturing

44. Automation in Manufacturing
• Automation are now perform operation
such as processing, assembly, inspection,
material handling, in some cases
accomplishing more than one of these
operations.

45. Classification of Automated
manufacturing system
• Fixed Automation
• Programmable Automation
• Flexible Automation

46. Fixed Automation
• Fixed automation is a system in
which sequence of processing
operation is fixed by the equipment
configuration.

47. Features of fixed automation
• High initial investments
• High production rates
• Relatively inflexible in accommodating
product variety

48. Examples of fixed automation
• Machining transfer lines
• Automation assembly machines.

49. Programmable Automation
• In Programmable Automation systems the
production equipments is designed with the
capability to change the sequence of
operation to accommodate different product
configuration.

50. Features of Programmable Automation
• High investment in general purpose
equipment
• Flower production rate than fixed automation
• Flexible to deal with variations and changes in
product configuration.
• More suitable for batch production

51. Examples of Programmable
Automation
• Numerical controlled machine tool
• Industrial robots
• Programmable logic controllers

52. Flexible Automation
• Flexible automation is capable of producing a
variety of parts with virtually no time lost for
changeover from one part style to the next.

53. • Continuous production of various mixtures of
products
• Medium production rate
• Flexibility to deal with product design
variations
Features of Flexible Automation

54. Fixed
Automation
Flexible
Automation
Programmable
Automation
Productvariety
Production quantity
100 10,000 1,000,000
Manual
Production

55. Factory
Operation
Design
Mfg.
Planning
Mfg.
Control
Business
Functions

57. GROUP TECHNOLOGY

58. GROUP TECHNOLOGY
• GT is a manufacturing philosophy in which
similar parts are identified and grouped
together to take advantage of their similarities
in manufacturing and design.
• Similar parts are arranged into part families.
– eg. A factory manufacturing 10000 different parts
may be categorized into 50 families.
• Each family will have some common
characteristics feature or parameters.

59. PART FAMILY
• A part family is a collection of parts which are
similar either because of geometric shape and
size or because similar processing steps are
required in their manufacture.
• Three methods of identifying part family:
1.Visual inspection
2.Part classification and coding schemes
3.Production flow analysis (PFA Chart)

60. Grouping according to
geometric similarities
Grouping according to
manufacturing similarities

61. Plant Layout
&
Group
Technology
Process type
Layout
GT
(Cellular)
Layou

62. FUNCTIONAL LAYOUTS ARE INEFFICIENT
PROCESS-TYPE LAYOUT
Lathe Milling Drilling
Grinding
Assembly
Receiving and
Shipping
L
L L
L
L
L
L
L M
MM
M M
M
A A
A A
D
D D
D
G
G
G
G G
G

63. Process Layout Characteristics
• Advantages
– Deep knowledge of the process
– Common tooling and fixtures
– Most Flexible -- can produce many different part types
• Disadvantages
– Spaghetti flow -- everything gets all tangled up
– Lots of in-process materials
– Hard to control inter-department activities
– Can be difficult to automate

64. PRODUCT LAYOUT
Shipping
L L M D
L M D
G
L M GG
A A
Receiving
Part #1
Part #3
Part #2

65. Product Layout Characteristics
• Advantages
– Easy to control -- input control
– Minimum material handling -- frequently linked to the next
process
– Minimal in-process materials
– Can be more easily automated
• Disadvantages
– Inflexible -- can only produce one or two parts
– Large setup
– Duplicate tooling is required for all cells

66. Cell #2
Cell #3
Cell #1
D D M I
D ML L I
D
M
L
M
I
CELLULAR LAYOUT

67. Cellular Layout Characteristics
• Advantages
– Control is simplified
– Common tooling and fixtures
– Flexible -- can produce many different part types - a part
family
• Disadvantages
– More Setup time required
– Need to know about many different processes

68. TRANSFER
LINE
SPECIAL
SYSTEM
FLEXIBLE
MANUFACTURING
SYSTEM
MANUFACTURING
Cells
STD. AND GEN.
MACHINERY
VOLUME
HIGH
VARIETY
LOW HIGH

70. Advantages of Group Technology
• Standardization of part design and minimization of
design duplication
• New parts can be developed using previous similar
designs.
• Data reflecting the experience of the part designer and
manufacturing process planner are stored in a database.
• Process plans are also standardized and scheduled more
efficiently.
• Setup times are reduced and parts are produced more
efficiently.
• Similar tools, clamps, jigs, fixtures and machinery are
shared.
• Needs to be implemented CIM, CAD/CAM and cellular
manufacturing. Potential savings 5 to 75 %.

71. Classification and Coding of Parts
• Design Attributes:
• External and internal shapes and dimensions
• Aspect ratio
• Tolerances specified
• Surface finish specified
• Part function
• Manufacturing Attributes:
• Primary processes
• Secondary and finishing processes
• Tolerances and Surface finish
• Sequence of operations
• Tools, dies, fixtures and machinery
• Production quantity and production rate

72. • Part Classification and Coding System
• • Classification means to sort similar parts into
predetermined groups based on appropriate
attributes (shape,manufacturing process, material,
etc.)
• • A code is a combination of letters and numbers
that are assigned to parts for information
processing

73. Coding Systems
• Types of Coding:
• Hierarchical coding (monocode)
• Polycoding (chain type)
• Decision-tree Coding (hybrid code)
• Major Industrial Coding Systems:
• Opitz System
• Multiclass System
• KK-3 system

74. Coding schemes
• Hierarchical
1 2
3
1 2
31 2
3
1 2
3

75. • Chain
1
2
3
.
.
1
2
3
.
.

76. Decision Tree Classification

77. OPITZ SYSTEM
• 12345 6789 ABCD
- Basic code consist of first 9 digits. This convey
both design and manufacturing data.
-Fi st digit alled fo ode
- Ne t digit alled supple e ta
ode
- Ne t digit ABCD alled se o da ode

80. A Simple Rotaional Part

82. Given the part design shown define the "form
code" using the Opitz system

86. MULTI CLASS SYSTEM
• This developed by the organization for
industrial research.
• This is relatively flexible.
• This used for variety of diff types of mfg
product.
• It uses a hierarchical or decision tree coding
structure.
• Coding structure up to 30 digits.

87. MULTI CLASS SYSTEM
Digit Function
0 – code system prefix
1 – main shape category
2,3 – external and internal configuration
4 - machined secondary elements
5,6 –Functional description
7-12 – Dimensional data (length,diameter)
13-Tolerances
14,15 – Material chemistry
16 – Raw material shape
17- production quantity
18- machined element orientation

89. PRODUCTION FLOW ANALYSIS(PFA)
• It does not use part classification and coding
system.
• It does not use part drawing
• It used to analyze the operation sequence and
machine routing.
• PFA uses manufacturing data rather than
design data.
• Dis adv: It provides no mechanism for
rationalizing the manufacturing routings.

90. PFA PROCEDURE
• 1.DATA COLLECTION
• 2. SORTING OF PROCESS ROUTINGS.
• 3.PFA CHART
• 4. ANALYSIS

91. • Part Family & Manufacturing Cell
Formation: General Procedure
• 1. Define the scope of the study including system boundaries
• 2. Identify the similarity attributes of interest
• 3. Simplify:
• Group obviously similar parts into representative part-type
• G oup pie es of e uip e t that ust sta togethe i to
representative machine-type
• 4. Find process plans using part-types and machine types
found in the previous step
• 5. Determine the Part-Machine Incidence Matrix
based on the process plans found in the previous step
• 6. Find the best Product Families and Machine Cells using
clustering methods.

93. EXAMPLE:
Consider a problem of 4 machines and 6 parts. Try
to group them.
Machines 1 2 3 4 5 6
M1 1 1 1
M2 1 1 1
M3 1 1 1
M4 1 1 1
93
Components

94. Machines 2 4 6 1 3 5
M1 1 1 1
M2 1 1 1
M3 1 1 1
M4 1 1 1
94
Components

95. Rank Order Clustering Algorithm:
Rank Order Clustering Algorithm is a simple
algorithm used to form machine-part groups.
95

96. Step 1: Assign binary weight and calculate a
decimal weight for each row and column using the
following formulas:
96
Decimal we
Decimal we bpj
n p
ight for row i = b
ight for column j =
ip
m-p
p=1
m
p=1
n
2
2

 

97. Step 2: Rank the rows in order of decreasing
decimal weight values.
Step 3: Repeat steps 1 and 2 for each column.
Step 4: Continue preceding steps until there is
no change in the position of each element in
the row and the column.
97

98. EXAMPLE:
Consider a problem of 5 machines and 10 parts. Try to group
them by using Rank Order Clustering Algorithm.
Machines 1 2 3 4 5 6 7 8 9 10
M1 1 1 1 1 1 1 1 1 1
M2 1 1 1 1 1
M3 1 1 1 1
M4 1 1 1 1 1 1
M5 1 1 1 1 1 1 1 1
98
Components
Table 1

99. Machines 1 2 3 4 5 6 7 8 9 10 Decimal
equivalent
M1 1 1 1 1 1 1 1 1 1 1007
M2 1 1 1 1 1 451
M3 1 1 1 1 568
M4 1 1 1 1 1 1 455
M5 1 1 1 1 1 1 1 1 1020
29 28 27 26 25 24 23 22 21 20
99
Binary weight
Components
Table 2

100. Binary
weight
Machines 1 2 3 4 5 6 7 8 9 10
24 M5 1 1 1 1 1 1 1 1
23 M1 1 1 1 1 1 1 1 1 1
22 M3 1 1 1 1
21 M4 1 1 1 1 1 1
20 M2 1 1 1 1 1
Decimal
equivalent
28 27 27 27 28 20 28 26 11 11
29 28 27 26 25 24 23 22 21 20
100
Binary weight
Components
Table 3

101. Binary
weight
Machines 1 5 7 2 3 4 8 6 9 10 Decimal
equivalent
24 M5 1 1 1 1 1 1 1 1 1020
23 M1 1 1 1 1 1 1 1 1 1 1019
22 M3 1 1 1 1 900
21 M4 1 1 1 1 1 1 123
20 M2 1 1 1 1 1 115
Decimal
equivalent
28 28 28 27 27 27 26 20 11 11
29 28 27 26 25 24 23 22 21 20
101
Binary weight
Components
Table 4

102. Manufacturing Cell Layout
• Once machine clusters are identified, one needs to
decide the best machine layout to
implement.
• For a good cell layout one must consider:
• -Technological considerations
• -Streamlined material flow
• Hollier methods specifies the machine layout that
maximizes the proportion of in-sequence
moves within the cell.

103. Hollier Method
• 1. Develop the From-To Chart
• 2. Determine the From/To ratio for each
a hi e di idi g the F o -su the To-
su fo ea h a hi e
• 3. Arrange the machines in order of
decreasing From/To ratios
• • Ma hi es ith high atios a e pla ed at the
beginning of the flow.
• • I the ase of ties, pla e a hi es ith
highe F o alues fi st.

104. Solve the problem using Hollier
Method 1:
2 3 1 4 From
2 - - 62 145 207
3 167 167
1 12 12
4 140 140
167 0 202 157
Step 1
17

105. Solve the problem using Hollier
Method :
2 3 1 4 From
2 - - 62 145 207
3 167 167
1 12 12
4 140 140
167 0 202 157
Step 1 Step 2
17
2 3 1 4 From
2 - - 62 145 207
3 167 167
1 12 12
4 140 140
167 0 202 157
Machine 3
first

106. Solve the problem using Hollier
Method :
2 1 4 From
2 - 62 145 207
1 12 12
4 140 140
To 0 202 157
Step 1 Step 2
17
2 1 4 From
2 - 62 145 207
1 12 12
4 140 140
To 0 202 157
Machine 2
next

107. Solve the problem using Hollier
Method1 :
1 4 From
1 12 12
4 140 140
To 140 12
Step 1 Step 2
17
1 4 From
1 12 12
4 140 140
To 140 12
3 2 4 1
The flow diagram
40
167
145 140
12
17
62
190
Machine 4 next

108. Solve the problem using Hollier
Method 2:
2 3 1 4 From
2 - - 62 145 207
3 167 167
1 12 12
4 140 140
167 0 202 157
From to From
to ratio
order
2 207 167 124 2
3 167 0 infinity 1
1 12 202 0.06 4
4 140 157 0.89 3
Step 1 Step 2
3 2 4 1
The flow diagram
167
40
167
145 140
12
17
62
190

110. Flexible Manufacturing System
• A highly automated GT machine cell,
consisting of a group of processing stations
(usually CNC machine tools), interconnected
by an automated material handling and
storage system, and controlled by an
integrated computer system

111. Five Types of FMS Layouts
• 1.In-line
• 2.Loop
• 3.Ladder
• 4.Open field
• 5.Robot-centered cell

112. In-line FMS Layouts

113. Loop FMS Layouts

114. Ladder FMS Layouts

115. Open field FMS Layouts

116. Robot-centered cell FMS Layouts

117. FMS Components
• Hardware components
– Workstations - CNC machines in a machining type
system
– Material handling system - means by which parts are
moved between stations
– Central control computer - to coordinate the activities
of the components so as to achieve a
– smooth overall operation of the system
• Software and control functions
• Human labor

118. Computer Functions in a FMS
• NC part programming - development of NC
programs for new parts introduced into the
system
• Production control - product mix, machine
scheduling, and other planning functions
• NC program download - part program commands
must be downloaded to individual stations
• Machine control - individual workstations require
controls, usually CNC

119. Computer Functions in a FMS
• Work part control - monitor status of each work part in
the system, status of pallet fixtures, orders on
loading/unloading pallet fixtures
• Tool management - tool inventory control, tool status
relative to expected tool life, tool changing and
resharpening, and transport to and from tool grinding
• Transport control - scheduling and control of work
handling system
• System management - compiles management reports on
performance (utilization, piece counts, production rates,
etc.)

120. Duties Performed by Human Labor
• Loading and unloading parts from the system
• Changing and setting cutting tools
• Maintenance and repair of equipment
• NC part programming
• Programming and operating the computer
system
• Overall management of the system

121. FMS Applications
• Machining –most
common application of
FMS technology
• Assembly
• Inspection
• Sheet metal processing
(punching, shearing,
bending, and forming)
• Forging

122. FMS Benefits
• Higher machine utilization than a
conventional machine shop due to better
work handling, off-line setups, and improved
scheduling
• Reduced work-in-process due to continuous
production rather than batch production
• Lower manufacturing lead times
• Greater flexibility in production scheduling