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Group MembersGroup Members
•Muhammad Rizwan Younas•Muhammad Abdullah
•Waqas Hussain
Presentation TitlePresentation Title
Process Selection and Facility Layout
Process Selection and Facility Layout
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 SelectionProcess Selection
Forecasting
Product andService Design
TechnologicalChange
CapacityPlanning
ProcessSelection
Facilities andEquipment
Layout
WorkDesign
Figure 6.1
Process Selection and Process Selection and System DesignSystem Design
• Key aspects of process strategy– Capital intensive – equipment/labor
– Process flexibility
– Technology
– Adjust to changes
– Design
– Volume
– technology
Process StrategyProcess Strategy
TechnologyTechnology
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 TechnologyKinds 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 AdvantageTechnology Competitive Advantage
Innovations in Products and services
Cell phones PDAs Wireless computing
Processing technology Increasing productivity Increasing quality Lowering costs
Technology AcquisitionTechnology 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
Variety How much
Flexibility What degree
Volume Expected output
Job Shop
Batch
Repetitive
Continuous
Process SelectionProcess Selection
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
Process TypesProcess Types
Process Type
Job Shop Batch Repetitive Continuous(flow)
Job Shop Appliance repair
Emergency room
Ineffective
Batch Commercialbaking
ClassroomLecture
Repetitive Automotiveassembly
Automaticcarwash
Continuous(flow)
Ineffective Steel ProductionWater purification
Figure 6.2
Product and Service Product and Service ProcessesProcesses
Dimension Job Shop Batch Repetitive Continuous(flow)
Job variety Very High Moderate Low Very low
Process flexibility
Very High Moderate Low Very low
Unit cost Very High Moderate Low Very low
Volume of output
Very High Low High Very low
Figure 6.2 (cont’d)Product – Process MatrixProduct – Process Matrix
Product and Process ProfilingProduct and Process Profiling Process selection can involve substantial
investment in Equipment Layout of facilities
Product profiling: Linking key product or service requirements to process capabilities
Key dimensions Range of products or services Expected order sizes Pricing strategies Expected schedule changes Order winning requirements
Automation: Machinery that has sensing and control devices that enables it to operate Fixed automation Programmable automation
AutomationAutomation
• Computer-aided design and manufacturing systems (CAD/CAM)
• Numerically controlled (NC) machines
• Robot
• Manufacturing cell
• Flexible manufacturing systems(FMS)
• Computer-integrated manufacturing (CIM)
AutomationAutomation
Layout: the configuration of departments, work centers, and equipment, with particular emphasis on movement of work (customers or materials) through the system
Product layouts
Process layouts
Fixed-Position layout
Combination layouts
Facilities LayoutFacilities Layout
Objective of Layout DesignObjective of Layout Design
1. Facilitate attainment of product or service quality
2. Use workers and space efficiently3. Avoid bottlenecks4. Minimize unnecessary material handling costs5. Eliminate unnecessary movement of workers
or materials6. Minimize production time or customer service
time7. Design for safety
Requires substantial investments of money and effort
Involves long-term commitments Has significant impact on cost and
efficiency of short-term operations
Importance of Layout DecisionsImportance of Layout Decisions
Product layouts
Process layouts
Fixed-Position layout
Combination layouts
Basic Layout TypesBasic Layout Types
Product layout Layout that uses standardized processing
operations to achieve smooth, rapid, high-volume flow
Process layout Layout that can handle varied processing
requirements Fixed Position layout
Layout in which the product or project remains stationary, and workers, materials, and equipment are moved as needed
Basic Layout TypesBasic Layout Types
Raw materialsor customer
Finished item
Station 2
Station 2
Station 3
Station 3
Station 4
Station 4
Material and/or labor
Station 1
Material and/or labor
Material and/or labor
Material and/or labor
Used for Repetitive or Continuous Processing
Figure 6.4 Product LayoutProduct Layout
High rate of output Low unit cost Labor specialization Low material handling cost High utilization of labor and equipment Established routing and scheduling Routing accounting and purchasing
Advantages of Product LayoutAdvantages of Product Layout
Creates dull, repetitive jobs Poorly skilled workers may not maintain
equipment or quality of output Fairly inflexible to changes in volume Highly susceptible to shutdowns Needs preventive maintenance Individual incentive plans are
impractical
Disadvantages of Product LayoutDisadvantages of Product Layout
1 2 3 4
5
6
78910
In
Out
Workers
Figure 6.6A U-Shaped Production LineA U-Shaped Production Line
Dept. A
Dept. B Dept. D
Dept. C
Dept. F
Dept. E
Used for Intermittent processingJob Shop or Batch Processes
Process Layout(functional)
Figure 6.7Process LayoutProcess Layout
Work Station 1
Work Station 2
Work Station 3
Figure 6.7 (cont’d)
Product Layout(sequential)
Used for Repetitive ProcessingRepetitive or Continuous Processes
Product LayoutProduct Layout
Can handle a variety of processing requirements
Not particularly vulnerable to equipment failures
Equipment used is less costly Possible to use individual incentive
plans
Advantages of Process LayoutsAdvantages of Process Layouts
In-process inventory costs can be high Challenging routing and scheduling Equipment utilization rates are low Material handling slow and inefficient Complexities often reduce span of supervision Special attention for each product or customer Accounting and purchasing are more involved
Disadvantages of Process LayoutsDisadvantages of Process Layouts
Fixed Position LayoutsFixed Position Layouts Fixed Position Layout: Layout in which the
product or project remains stationary, and workers, materials, and equipment are moved as needed.
Nature of the product dictates this type of layout Weight Size Bulk
Large construction projects
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 LayoutsCellular Layouts
Dimension Functional CellularNumber of moves between departments
many few
Travel distances longer shorter
Travel paths variable fixed
Job waiting times greater shorter
Throughput time higher lower
Amount of work in process
higher lower
Supervision difficulty higher lower
Scheduling complexity higher lower
Equipment utilization lower higher
Table 6.3Functional vs. Cellular LayoutsFunctional vs. Cellular Layouts
Warehouse and storage layouts Retail layouts Office layouts Service layouts must be aesthetically
pleasing as well as functional
Service LayoutsService Layouts
Line Balancing is the process of assigning tasks to workstations in such a way that the workstations have approximately equal time requirements.
Design Product Layouts: Design Product Layouts: Line BalancingLine Balancing
Cycle time is the maximum time allowed at each workstation tocomplete its set of tasks on a unit.
Cycle TimeCycle Time
D
OT = timecycle = CT
rateoutput Desired= D
dayper timeoperating OT
CT
OT = rateOutput
D
OT = timecycle = CT
rateoutput Desired= D
dayper timeoperating OT
CT
OT = rateOutput
Determine Maximum OutputDetermine Maximum Output
task timeof sum = t
CT
t)( =N
Determine the Minimum Number Determine the Minimum Number
of Workstations Requiredof Workstations Required
Precedence diagram: Tool used in line balancing to display elemental tasks and sequence requirements
A Simple Precedence Diagrama b
c d e
0.1 min.
0.7 min.
1.0 min.
0.5 min. 0.2 min.
Figure 6.10Precedence DiagramPrecedence Diagram
Arrange tasks shown in Figure 6.10 into three workstations. Use a cycle time of 1.0 minute Assign tasks in order of the most number
of followers
Example 1: Example 1: Assembly Line BalancingAssembly Line Balancing
Workstation
TimeRemaining
EligibleAssignTask
RevisedTime Remaining
StationIdle Time
1 1.0
0.9
0.2
a, c
c
none
a
c
-
0.9
0.2
0.2
2 1.0 b b 0.0 0.0
3 1.0
0.5
0.3
d
e
-
d
e
-
0.5
0.3 0.3
0.5
Example 1: SolutionExample 1: Solution
Percent idle time = Idle time per cycle
(N)(CT)
Efficiency = 1 – Percent idle time
Calculate Percent Idle TimeCalculate Percent Idle Time
Assign tasks in order of most following tasks. Count the number of tasks that follow
Assign tasks in order of greatest positional weight.
Positional weight is the sum of each task’s time and the times of all following tasks.
Some Heuristic (intuitive) Rules:
Line Balancing RulesLine Balancing Rules
c d
a b e
f g h
0.2 0.2 0.3
0.8 0.6
1.0 0.4 0.3
Example 2Example 2
Station 1 Station 2 Station 3 Station 4
a b ef
d
g h
c
Solution to Example 2Solution to Example 2
1 min.2 min.1 min.1 min. 30/hr. 30/hr. 30/hr. 30/hr.
Bottleneck
Bottleneck WorkstationBottleneck Workstation
Parallel WorkstationsParallel Workstations
1 min.
2 min.
1 min.1 min. 60/hr.
30/hr. 30/hr.
60/hr.
2 min.
30/hr.30/hr.
Parallel Workstations
Information Requirements:
1. List of departments
2. Projection of work flows
3. Distance between locations
4. Amount of money to be invested
5. List of special considerations
6. Location of key utilities
Designing Process LayoutsDesigning Process Layouts
1 3 2
30
170 100
A B C
Figure 6.12
Example 3: Example 3: Interdepartmental Work FlowsInterdepartmental Work Flows
for Assigned Departmentsfor Assigned Departments
Any Question.????Any Question.????