Mata kuliah : J0444 - Manajemen Operasional
Tahun
: 2010
System Design:
Process Selection and Facility Layout
Pertemuan 07
Learning Objectives
•
•
•
•
•
Explain the strategic importance of process selection.
Explain the influence that process selection has on an
organization.
Describe the basic processing types.
Discuss automated approaches to processing.
Explain the need for management of technology.
Learning Objectives
•
•
•
•
•
List some reasons for redesign of layouts.
Describe the basic layout types.
List the main advantages and disadvantages of
product layouts and process layouts.
Solve simple line-balancing problems.
Develop simple process layouts.
Introduction
• Process selection
– Deciding on the way production of goods or services will be
organized
• Major implications
–
–
–
–
Capacity planning
Layout of facilities
Equipment
Design of work systems
Process Selection and System Design
Forecasting
Capacity
Planning
Product and
Service Design
Technological
Change
Facilities and
Equipment
Layout
Process
Selection
Work
Design
Process Strategy
• Key aspects of process strategy
–
Capital intensive – equipment/labor
–
Process flexibility
–
Technology
–
Adjust to changes
–
Design
–
Volume
–
technology
Technology
• Technology: The application of scientific discoveries to
the development and improvement of products and
services and operations processes.
• Technology innovation: The discovery and
development of new or improved products, services, or
processes for producing or providing them.
Kinds of Technology
• Operations management is primarily concerned with three
kinds of technology:
– Product and service technology
– Process technology
– Information technology
• All three have a major impact on:
– Costs
– Productivity
– Competitiveness
Technology Competitive Advantage
• Innovations in
– Products and services
• Cell phones
• PDAs
• Wireless computing
– Processing technology
• Increasing productivity
• Increasing quality
• Lowering costs
Technology Acquisition
• Technology can have benefits but …
• Technology risks include:
– What technology will and will not do
– Technical issues
– Economic issues
•
•
•
•
Initial costs, space, cash flow, maintenance
Consultants and/or skilled employees
Integration cost, time resources
Training, safety, job loss
Process Selection
• Variety
Batch
– How much
• Flexibility
– What degree
• Volume
Job Shop
Repetitive
– Expected output
Continuous
Process Types
• Job shop
– Small scale
• Batch
– Moderate volume
• Repetitive/assembly line
– High volumes of standardized goods or services
• Continuous
– Very high volumes of non-discrete goods
Product and Service Processes
Process Type
Job Shop
Appliance repair
Emergency
room
Ineffective
Commercial
baking
Batch
Classroom
Lecture
Automotive
assembly
Repetitive
Automatic
carwash
Continuous
(flow)
Ineffective
Steel Production
Water purification
Automation
• Automation: Machinery that has sensing and control
devices that enables it to operate
– Fixed automation
– Programmable automation
• Computer-aided design and manufacturing systems
(CAD/CAM)
• Numerically controlled (NC) machines
• Robot
• Manufacturing cell
• Flexible manufacturing systems(FMS)
• Computer-integrated manufacturing (CIM)
What is Facility Layout
• Location or arrangement of everything within & around
buildings
• Objectives are to maximize
– Customer satisfaction
– Utilization of space, equipment, & people
– Efficient flow of information, material, & people
– Employee morale & safety
Strategic Importance of Layout
Proper layout enables:
• Higher utilization of space, equipment,and people
• Improved flow of information, materials, or people
• Improved employee morale and safer working
conditions
• Improved customer/client interaction
• Flexibility
Types of Layouts
•
•
•
•
•
•
Fixed-position layout
Process-oriented layout
Office layout
Retail layout
Warehouse layout
Product-oriented layout
Six Layout Strategies
• Fixed-position layout
– large bulky projects such as ships and buildings
• Process-oriented layout
– deals with low-volume, high-variety production (“job shop”,
intermittent production)
• Office layout
– positions workers, their equipment, and spaces/offices to
provide for movement of information
Six Layout Strategies - continued
• Retail/service layout
– allocates shelf space and responds to customer behavior
• Warehouse layout
– addresses trade-offs between space and material handling
• Product-oriented layout
– seeks the best personnel and machine use in repetitive or
continuous production
Layout Example - Office
Product Layout
Raw
materials
or customer
Material
and/or
labor
Station
1
Material
and/or
labor
Station
2
Material
and/or
labor
Station
3
Station
4
Material
and/or
labor
Used for Repetitive or Continuous Processing
Finished
item
A U-Shaped Production Line
In
1
2
3
4
5
Workers
6
Out
10
9
8
7
Process Layout
Process Layout
(functional)
Dept. A
Dept. C
Dept. E
Dept. B
Dept. D
Dept. F
Used for Intermittent processing
Job Shop or Batch Processes
Requirements of a Good Layout
3 an understanding of capacity and space
requirements
3 selection of appropriate material handling
equipment
3 decisions regarding environment and
aesthetics
3 identification and understanding of the
requirements for information flow
3 identification of the cost of moving between
the various work areas
Constraints on Layout Objectives
•
•
•
•
Product design & volume
Process equipment & capacity
Quality of work life
Building and site
Areas of Concern in Layout Strategy
Communication
Service
Areas
Warehousing
Safety
Material
Attributes
Layout
Strategy
Work
Cell
Material
Flow
Fixed-Position Layout
• Design is for stationary project
• Workers and equipment come to site
• Complicating factors
– Limited space at site
– Changing material needs
Process-Oriented Layout
• Design places departments with large flows of material
or people together
• Department areas having similar processes located in
close proximity
– e.g., All x-ray machines in same area
• Used with process-focused processes
Steps in Developing
a Process-Oriented Layout
Construct a “from-to matrix”
Determine space requirements for each department
Develop an initial schematic diagram
Determine the cost of this layout
By trial-and-error (or more sophisticated means), try
to improve the initial layout
6 Prepare a detailed plan that evaluates factors in
addition to transportation cost
1
2
3
4
5
Cost of Process-Oriented Layout
n
n
Minimize cost   X ijC ij
i 1 j1
where n  total number of work centers
or department s
i, j  individual department s
X ij  number of loads moved from
department i to department j
C ij  cost to move a load between
department i and department j
Interdepartmental Flow of Parts
1
1
2
3
4
5
6
2
50
3
4
5
6
100
0
0
20
30
50
10
0
20
0
100
50
0
0
Interdepartmental Flow Graph Showing Number of
Weekly Loads
10
0
1
50
2
30
3
100
10
4
50
5
6
Possible Layout 1
Room 1
Room 2
Room 2
Assembly
Printing
Machine Shop
Department
Department
Department
(1)
(2)
(3)
Receiving
Shipping
Testing
Department
Department
Department
40’
(4)
Room 4
(5)
Room 5
(6)
Room 6
60’
Interdepartmental Flow Graph Showing Number of
Weekly Loads
30
1
50
2
10
0
3
100
4
50
5
6
Possible Layout 3
Room 1
Room 2
Room 2
Painting
Assembly
Machine Shop
Department
Department
Department
(2)
(1)
(3)
Receiving
Shipping
Testing
Department
Department
Department
40’
(4)
Room 4
(5)
Room 5
(6)
Room 6
60’
Cellular Layouts
• Cellular Production
–
Layout in which machines are grouped into a cell
that can process items that have similar processing
requirements
• Group Technology
–
The grouping into part families of items with similar
design or manufacturing characteristics
Cellular Layout - Work Cells
• Special case of product-oriented layout - in what is
ordinarily a process-oriented facility
• Consists of different machines brought together to
make a product
• Temporary arrangement only
• Example: Assembly line set up to produce 3000
identical parts in a job shop
Improving Layouts by
Moving to the Work Cell Concept
Work Cell Floor Plan
Saws
Tool Room
Drills
Work Cell
Office
Office Layout
 Design positions people, equipment, & offices for
maximum information flow
 Arranged by process or product

Example: Payroll dept. is by process
 Relationship chart used
 Examples

Insurance company
 Software company
Office Layout Floor Plan
Accounting
Finance
Fin.
Manager
Acct.
Brand X
Relationship Chart
1 President
1
O
2 Costing
2
U
A
3 Engineering
I = Important
U = Unimportant
A
4
I
O
4 President’s Secretary
Ordinary
closeness:
President (1) &
3 Costing (2)
Absolutely
necessary:
President (1) &
Secretary (4)
Office Relationship Shart
1 President
O
2 Chief Technology Officer
3 Engineer’s Area
4 Secretary
5 Office entrance
7 Equipment cabinet
8 Photocopy equipment
9 Storage room
9 Storage room
A
U
O
I
A
A
I
I
I
X
A I
I
I
O
U E
E
U
O U
A
E
E A
X
O U
E U
O
I O
U O
Val.
Closeness
A
Absolutely
necessary
E
Especially
important
I
Important
O
Ordinary OK
U
Unimportant
X
Not desirable
Retail/Service Layout
 Design maximizes product exposure to customers
 Decision variables


Store flow pattern
Allocation of (shelf) space to products
 Types

Grid design
 Free-flow design
Video
Retail /Service Layout Grid Design
Grocery Store
Bread
Meat
Milk
Produce
Carts
Frozen Foods
Office
Checkout
Store Layout - with Dairy, Bread, High
Drawer Items in Corners
Retail/Service Layout Free-Flow Design
Apparel Store
Trans.
Counter
Feature
Display
Table
Retail Store Shelf Space Planogram
2 ft.
SUAVE
SUAVE
VO-5
PERT
VO-5
PERT
PERT
VO-5
PERT
VO-5
VO-5
PERT
 Computerized tool
for shelf-space
management
 Generated from
store’s scanner
data on sales
 Often supplied by
manufacturer
5 facings
A Good Service Layout (Servicescape)
Considers
• Ambient conditions - background characteristics such as
lighting, sound, smell, and temperature.
• Spatial layout and functionality - which involve customer
circulation path planning
• Signs, Symbols, and Artifacts - characteristics of building
design that carry social significance
Warehouse Layout
 Design balances space (cube)
utilization & handling cost
 Similar to process layout

Items moved between dock
& various storage areas
 Optimum layout depends on

Variety of items
stored
 Number of items picked
Warehouse Layout Floor Plan
Conveyor
Truck
Zones
Order Picker
Product-Oriented Layout
• Facility organized around product
• Design minimizes line imbalance
– Delay between work stations
• Types: Fabrication line; assembly line
Product-Oriented Requirements
•
•
•
•
Standardized product
High production volume
Stable production quantities
Uniform quality of raw materials & components
Design Product Layouts: Line Balancing
Line Balancing is the process of assigning
tasks to workstations in such a way that
the workstations have approximately
equal time requirements.
Assembly Line Balancing
• Analysis of production lines
• Nearly equally divides work between
workstations while meeting required output
• Objectives
– Maximize efficiency
– Minimize number of
work stations
Assembly Line Balancing
The General Procedure
• Determine cycle time by taking the demand (or
production rate) per day and dividing it into the
productive time available per day
• Calculate the theoretical minimum number of
work stations by dividing total task time by cycle
time
• Perform the line balance and assign specific
assembly tasks to each work station
Assembly Line Balancing Steps
1.
2.
3.
4.
5.
6.
7.
8.
Determine tasks (operations)
Determine sequence
Draw precedence diagram
Estimate task times
Calculate cycle time
Calculate number of work stations
Assign tasks
Calculate efficiency
Precedence Diagram Example
10 Min.
A
11
B
C
4
5
3
7
3
F
G
I
D
12
11
E
H
Assembly Line Balancing Equations
Production time available
Cycle time
Minimum
number of
work
stations
Efficiency
=
Demand per day
 Task times
=
=
Cycle time
 Task times
(Actual number
* (Cycle time)
of work
stations)
Six Station Solution
5
C
10
11
A
B
3
7
F
G
3
I
D
12
11
E
H
The End