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1. Chapter 10 – Facility Layout
Operations Management

2. Learning Objectives
 Define layout planning and its importance
 Identify and describe different types of layouts
 Compare process layouts & product layouts
 Describe the steps involved in designing both
process and product layouts
 Explain the advantages of hybrid layouts
 Define the meaning of group technology & its
importance to cellular layouts

3. What Is Layout Planning
 Layout planning is determining the best
physical arrangement of resources
within a facility
 Two broad categories of operations:
 Intermittent processing systems
 Continuous processing systems

4. Types of Layouts
 Process layouts:
 Group similar resources together
 Product layouts:
 Designed to produce a specific product efficiently
 Hybrid layouts:
 Combine aspects of both process and product layouts
 Fixed-Position layouts:
 Product is two large to move; e.g. a building

5. Process Layouts
 General purpose & flexible resources
 Lower capital intensity & automation
 Higher labor intensity
 Resources have greater flexibility
 Processing rates are slower
 Material handling costs are higher
 Scheduling resources & work flow is more
complex
 Space requirements are higher

6. Product Layouts
 Specialized equipment
 High capital intensity & wide use of
automation
 Processing rates are faster
 Material handling costs are lower
 Less space required for inventories
 Less volume or design flexibility

7. Hybrid Layouts
 Combine elements of both product &
process layouts
 Maintain some of the efficiencies of product
layouts
 Maintain some of the flexibility of process
layouts
 Examples:
 Group technology & manufacturing cells
 Grocery stores

8. Comparison of Product vs. Product Layouts
Process Layouts Product Layouts
Products: large #, different small # efficiently
Resources: general purpose specialized
Facilities: more labor intensive more capital intensive
Flexibility: greater relative to market lower relative to market
Processing slower faster
Rates:
Handling costs: high low
Space requirements: higher lower

9. Designing Process Layouts
 Step 1: Gather information:
 Space needed, space available, importance of
proximity between various units
 Step 2: Develop alternative block plans:
 Using trial-and-error or decision support tools
 Step 3: Develop a detailed layout
 Consider exact sizes and shapes of departments
and work centers including aisles and stairways
 Tools like drawings, 3-D models, and CAD
software are available to facilitate this process

10. Process Layout Steps
 Step 1: Gather information like space needed, from-to matrix,
and REL Chart for Recovery First Sports Medicine Clinic (total
space 3750 sq. ft.)
A B C
Radiology Laboratory Lobby &
Waiting
400 sq. ft. 300 sq. ft. 300 sq. ft.
D E F
Examining Surgery & Physical
Rooms Recovery Therapy
800 sq. ft. 900 sq. ft. 1050 sq. ft.

11. Step 1: Gather Information (continued)

12. Step 2: Develop a New Block Layout
 Use trial and error with
from-to and REL Charts as a guide
 Use computer software like ALDEP
or CRAFT

13. Warehouse Layouts
 Warehouse Layout Considerations:
 Primary decision is where to locate each department
relative to the dock
 Departments can be organized to minimize “ld”
totals
 Departments of unequal size require modification of
the typical ld calculations to include a calculation
of the “ratio of trips to area needed”
 The usage of “Crossdocking” (see Ch.4) modifies
the traditional warehouse layouts; more docks, less
storage space, and less order picking

14. Office Layouts
 Office Layout Considerations:
 Almost half of US workforce works in an office
environment
 Human interaction and communication are the primary
factors in designing office layouts
 Layouts need to account for physical environment and
psychological needs of the organization
 One key layout trade-off is between proximity and
privacy
 Open concept offices promote understanding & trust
 Flexible layouts incorporating “office landscaping” help
to solve the privacy issue in open office environments

15. Designing Product Layouts
 Step 1:
Identify tasks & immediate predecessors
 Step 2:
Determine the desired output rate
 Step 3:
Calculate the cycle time
 Step 4:
Compute the theoretical minimum number
of workstations
 Step 5: Assign tasks to workstations (balance the
line)
 Step 6: Compute efficiency, idle time & balance
delay

16. Step 1: Identify Tasks &
Immediate Predecessors
Example 10.4 Vicki's Pizzeria and the Precedence Diagram
Immediate Task Time
Work Element Task Description Predecessor (seconds
A Roll dough None 50
B Place on cardboard backing A 5
C Sprinkle cheese B 25
D Spread Sauce C 15
E Add pepperoni D 12
F Add sausage D 10
G Add mushrooms D 15
H Shrinkwrap pizza E,F,G 18
I Pack in box H 15
Total task time 165

17. Layout Calculations
 Step 2: Determine output rate
 Vicki needs to produce 60 pizzas per hour
 Step 3: Determine cycle time
 The amount of time each workstation is allowed to
complete its tasks
available time ( sec./day ) 60 min/hr x 60 sec/min
Cycle time (sec./unit) = = = 60 sec./unit
desired output ( units/hr ) 60 units/hr
 Limited by the bottleneck task (the longest task in a
process):
available time 3600 sec./hr.
Maximum output = = = 72 units/hr, or pizzas per hour
bottleneck task time 50 sec./unit

18. Layout Calculations (continued)
 Step 4: Compute the theoretical minimum
number of stations
 TM = number of stations needed to
achieve 100% efficiency (every second is
used)
TM =
∑ ( task times ) = 165 seconds
= 2.75, or 3 stations
cycle time 60 sec/station
 Always round up (no partial workstations)
 Serves as a lower bound for our analysis

19. Layout Calculations (continued)
 Step 5: Assign tasks to workstations
 Start at the first station & choose the longest eligible task following
precedence relationships
 Continue adding the longest eligible task that fits without going over the
desired cycle time
 When no additional tasks can be added within the desired cycle time, begin
assigning tasks to the next workstation until finished
Workstation Eligible task Task Selected Task time Idle time
A A 50 10
1
B B 5 5
C C 25 35
2 D D 15 20
E, F, G G 15 5
E, F E 12 48
F F 10 38
3
H H 18 20
I I 15 5

20. Last Layout Calculation
 Step 6: Compute efficiency and balance delay
 Efficiency (%) is the ratio of total productive
time divided by total time
Efficiency (%) =
∑t = 165 sec.
( 100) = 91.7%
NC 3 stations x 60 sec.
 Balance delay (%) is the amount by which the
line falls short of 100%
Balance delay = 100% − 91.7% = 8.3%

21. Other Product Layout Considerations
 Shape of the line (S, U, O, L):
 Share resources, enhance communication &
visibility, impact location of loading &
unloading
 Paced versus un-paced lines
 Paced lines use an automatically enforced
cycle time
 Single or mixed-model lines

22. Designing Hybrid Layouts
 One of the most popular hybrid layouts uses Group
Technology (GT) and a cellular layout
 GT has the advantage of bringing the efficiencies of a
product layout to a process layout environment

23. Process Flows before the Use of GT Cells

24. Process Flows after the Use of GT Cells

25. Chapter 10 Highlights
 Layout planning is deciding on the best physical
arrangement of resources.
 There are four basic types of layouts: process,
product, hybrid, and fixed position.
 Process layouts provide flexibility to make a
variety of different products. Product layouts
provide greater efficiency for one product.
 The steps for designing process layouts are:
gather space and closeness information, develop a
block plan, and develop a detailed layout.

26. Chapter 10 Highlights (continued)
 The steps for designing an product layout are:
identify tasks and predecessors, determine output
rate, determine cycle time, computing the
theoretical minimum number of work stations,
assigning tasks to workstations, and computing
efficiency and balance delay.
 Hybrids layouts combine elements from both types
of layouts to increase efficiency.
 Hybrid layouts combine GT analysis with cellular
layout concepts .

27. The End
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