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/ /١٤٤٤ ٠٩ ٢٩ 13:10Dr.Kasser Naser Mansour- KAU-KSA1
/ /١٤٤٤ ٠٩ ٢٩ 13:10Dr.Kasser Naser Mansour- KAU-KSA2
/ /١٤٤٤ ٠٩ ٢٩ 13:10Dr.Kasser Naser Mansour- KAU-KSA3
/ /١٤٤٤ ٠٩ ٢٩ 13:10Dr.Kasser Naser Mansour- KAU-KSA4
/ /١٤٤٤ ٠٩ ٢٩ 13:10Dr.Kasser Naser Mansour- KAU-KSA5
/ /١٤٤٤ ٠٩ ٢٩ 13:106 Dr.Kasser Naser Mansour- KAU-KSA
أن يجب المناسب الترتيب قرار نتخذ أن قبلالتالية األسئلة عن :نجيب
1. What centers should the layout include?2. How much space and capacity does each center
need?3. How should each center’s space be configured?4. Where should each center be located?
Layout Planning Questions تخطيط مسائلالترتيب
Location Dimensions ابعادالموقع
• The location of a center has two dimensions:
1. Relative location: The placement of a center relative to other centers.
2. Absolute location: The particular space that the center occupies within the facility.
How Process Layout العملية ترتيب يتم كيف fits the Operations Management Philosophy
Operations As a Competitive Weapon
Operations StrategyProject Management Process Strategy
Process AnalysisProcess Performance and Quality
Constraint ManagementProcess Layout
Lean Systems
Supply Chain StrategyLocation
Inventory ManagementForecasting
Sales and Operations PlanningResource Planning
Scheduling
Product LayoutInput Data and Activities
1 .Flow of Materials 2 .Activity Relationships
3 .Relationship Diagram
4 .Space Requirements 5 .Space Available
6 .Space Relationship Diagram
7 .Modifying Considerations 8 .Practical Limitations
9 .Develop Layout Alternatives
10 .Evaluation
An
alys
isS
earc
hS
elec
tio
n
Absolute Locations vs. Relative Locations
Original layout
Frozen foods
Dry groceries
Bread Vegetables
Meats
Frozen foods
Dry groceries
BreadVegetables
Meats
Revised layout
Four of the absolute locations have changed but
not the relative locations .
Strategic Issues
• Layout choices can help communicate an organization’s product plans and competitive priorities.
• Altering a layout can affect an organization and how well it meets its competitive priorities in the following ways:
1. Increasing customer satisfaction and sales at a retail store.2. Facilitating the flow of materials and information.3. Increasing the efficient utilization of labor and equipment.4. Reducing hazards to workers.5. Improving employee morale.6. Improving communication.
Performance Criteria
• Customer satisfaction• Level of capital investment• Requirements for materials handling• Ease of stock picking• Work environment and “atmosphere”• Ease of equipment maintenance• Employee and internal customer attitudes• Amount of flexibility needed• Customer convenience and levels of sales
Types of Layouts
• Flexible-flow layout: A layout that organizes resources (employees) and equipment by function rather than by service or product.
• Line-flow layout: A layout in which workstations or departments are arranged in a linear path.
• Hybrid layout: An arrangement in which some portions of the facility have a flexible-flow and others have a line-flow layout.
• Fixed-position layout: An arrangement in which service or manufacturing site is fixed in place; employees along with their equipment, come to the site to do their work.
A Flexible Flow Layout
FoundryMilling
machines
LathesGrinding
Painting Drills
Office
Welding
Forging
A job shop has a flexible-flow layout.
• ( النقل تكاليف مسألة هي هنا المسألة: هي( حلها وطرائق ، والمناولة
البسيطة- 1 المخططات طريقةالعملية- 2 تتابع تحليل طريقةالمقطوعة- 3 المسافة في العبء تحليل طريقةالحاسب- 4 بستخدام التحليل طريقة
/ /١٤٤٤ ٠٩ ٢٩ 13:1016 Dr.Kasser Naser Mansour- KAU-KSA
17
18
XA
O
E
AAbsolutely NecessaryEEspecially ImportantIImportant
OOrdinary Closeness O.K.UUnimportantXUndesirable
A and X > E > I > O > U
19
20
Layout Design الترتيب تصميم• Three concepts: مفاهيم :ثالثة
– Layout Evaluation الترتيب تقييم– Layout Construction الترتيب تشكيل– Layout Improvement الترتيب أهمية
• What to use as input data? كمدخالت؟ بيانات نستخدم ماذا – Relationships – closeness ratings وأماكن والشعب األقسام بين المغلقة العالقات عدد
العمل• Subjective• May take long time to prepare
– Flow data البيانات تدفق• Objective• May not be very stable
• How to Evaluate the Layout Plans? – Objective Function الترتيب خطط نقيم كيف– Distance Based– Adjacency Based
21
Layout Evaluation تقييم التريتب
An Algorithm جيدة خطط بين تقارن التقيم عمليةسيء قائم وآخر
s = g (X ) يلي كما نموذج :نطوnر–Adjacency-based scoring (Komsuluk Bazli Skorlama)
• Based on the relationship chart and diagram
• Xi is the number of times an adjacency i is satisfied, i=A, E, I, O, U, X• Aldep uses (wi values) A=64, E=16, I=4, O=1, U=0, and X=-1024• Scoring model has intuitive appeal; the ranking of layouts is sensitive to the
weight values. Layout “B” may be preferred to “C” with certain weights but not with others.
• Therefore, the specification of the weights is very important.• The weights wi can also be represented by the flow amounts between the
adjacent departments instead of scores assigned to A, E, I, O, U, X.
6
1
i
iiXwsMax
22
12
34
56
7
12
34
56
7
UU
UU
IE
UI
OU
A
OI
UI
IE
U
OU
EReceivingReceiving
MillingMilling
PressPress
Screw MachineScrew Machine
AssemblyAssembly
PlatingPlating
ShippingShipping
3
Press
7
Shipping
6Plating
2
Milling
4
Screw Machine
5
Assembly
1
Receiving
A
E I
E
O
I
O
1234567
1 2 3 4 5 6 7
I OE I U
O U
AE
4+1 =5
16+4+0 =20
1+0 =1
----
64 =64
16 =16
Total Score 106
Example
U U
23
Exercise:Exercise: Find the score of the layout shown below. Use A=8, E=4, I=2, O=1, U=0 and X=-8.
12
34
56
7
12
34
56
7
UU
UU
IE
UI
OU
A
OI
UI
IE
U
OU
EReceivingReceiving
MillingMilling
PressPress
Screw MachineScrew Machine
AssemblyAssembly
PlatingPlating
ShippingShipping
3Press
7Shipping
6Plating
4Screw
Machine
1Receiving
2Milling
5Assembly
24
Layout Evaluation (cont’d)–Distance-based scoring (Mesafe Bazli Skorlama)
• Approximate the cost of flow between activities• Requires explicit evaluation of the flow volumes and costs
• cij covers both the i to j and the j to i material flows
• Dij can be determined with any appropriate distance metric–Often the rectilinear distance between department centroids
• Assumes that the material flow system has already been specified (cij=flow required* cost /flow-distance)
• Assumes that the variable flow cost is proportional to distance• Distance often depends on the aisle layout and material handling
equipment
1
1 1
m
i
m
ijijijDcsMin
25
Layout Evaluation – Distance Based Scoring
Example
A B
C D
Initial Layout
From/To A B C DA - 2 4 4B 1 - 1 3C 2 1 - 2D 4 1 0 -
Flow Data
From/To A B C DA - 40 25 55B 40 - 65 25C 25 65 - 40D 55 25 40 -
Distance DataFrom/To A B C D Total
A - 80 100 220 400B 40 - 65 75 180C 50 65 - 80 195D 220 25 0 - 245
Total 310 170 165 375 1020
Total Cost
26
Layout Evaluation – Distance-Based Scoring
–Distance-based scoring–Impact of aisle layout and direction of travel
A B
C D
Warehouse LayoutsOut-and-back Pattern
• The most basic warehouse layout is the out-and-back pattern. The numbers indicate storage areas for same or similar items.
Dock Aisle
Storage area
Storage area
3556427
1554427
Warehouse Layouts Zone System
Click to add titleZones Zones Control
station Shipping doors
Tractor trailer
Tractor trailer
Overflow
Feeder lines
Feeder lines
Office Layouts المكتب تخطيط
• Most formal procedures for designing office layouts try to maximize the proximity of workers whose jobs require frequent interaction.
• Privacy is another key factor in office design.• Four common office layouts:
1. Traditional layouts
2. Office landscaping (cubicles/movable partitions)
3. Activity settings
4. Electronic cottages (Telecommuting)
Line Flow Layout
Station 1 Station 2 Station 3 Station 4
A production line has a line-flow layout.
Group Technology (GT)
• Group Technology (GT) is an option for achieving line-flow layouts with low-volume processes; this technique creates cells not limited to just one worker and has a unique way of selecting work to be done by the cell.
• The GT method groups parts or products with similar characteristics into families and sets aside groups of machines for their production.
Before Group Technology
Drilling
D D
D D
Grinding
G G
G G
G G
Milling
M M
M M
M M
Assembly
A A
A A
Lathing
Receiving and shipping
L
L L
L L
L L
L
Jumbled flows in a job shop without GT cellsJumbled flows in a job shop without GT cells
Applied Group TechnologyLine flows in a job shop with three GT cellsLine flows in a job shop with three GT cells
Cell 3
L M G G
Cell 1 Cell 2
Assembly area
A A
L M DL
L MShipping
D
Receiving
G
Designing Flexible-Flow Layouts
• Step 1: Gather information– Space requirements by center– Available space– Closeness factors: which centers need to be located close to one
another.
• Closeness matrix: A table that gives a measure of the relative importance of each pair of centers being located close together.
• Step 2: Develop a Block plan: A plan that allocates space and indicates placement of each department.
• Step 3: Design a detailed layout.
Gather Information
100'
150'
3 6 4
1 2 5
Current Block Plan
Department Area Needed (ft2)
1 .Administration3,5002 .Social services2,6003 .Institutions2,4004 .Accounting1,6005 .Education1,5006 .Internal audit3,400
Total15,000
Space Requirements
Example : Office of Budget Management
100'
150'
3 6 4
1 2 5 Closeness Matrix
Trips between Departments
Department 1 2 3 4 5 6
1. Administration —
2. Social services —
3. Institutions —
4. Accounting —
5. Education —
6. Internal audit —
3 6 5 6 10
8 1 1
3 9
2
1
Departments 1 and 6 have the most interaction.Departments 3 and 5 have the next highest.
Departments 2 and 3 have next priority.
Example 8.1 Office of Budget Management
100'
150'
100'
150'
3 6 4
1 2 5 Proposed Block Plan
First put departments 1 and 6 close together
1
6
Next put departments 3 and 5 close together
5
3
Then put departments 2 and 3 close together
2
4
• Weighted-distance method: A mathematical model used to evaluate flexible-flow layouts based on proximity factors.
• Euclidean distance is the straight-line distance, or shortest possible path, between two points.
• Rectilinear distance: The distance between two points with a series of 90 degree turns, as along city blocks.
Applying the Weighted- Distance Method
Distance Measures
Rectilinear DistanceRectilinear Distance
ddABAB = |= |xxAA –– x xBB| + || + |yyAA – – yyBB||
Euclidian DistanceEuclidian Distance
ddABAB = (= (xxAA –– x xBB))22 + ( + (yyAA – – yyBB))22
©2007 Pearson Education
Example 2 : Load Distance Analysis
Current Plan Proposed Plan
Dept Closeness Distance DistancePair Factor, w d wd Score d wd Score
1,2 3 1 3 2 61,3 6 1 6 3 181,4 5 3 15 1 51,5 6 2 12 2 121,6 10 2 20 1 102,3 8 2 16 1 82,4 1 2 2 1 12,5 1 1 1 2 23,4 3 2 6 2 63,5 9 3 27 1 94,5 2 1 2 1 25,6 1 2 2 3 3
ld =112 ld = 82
Calculating the WD Score
Designing Line-Flow Layouts
• Line balancing is the assignment of work to stations in a line so as to achieve the desired output rate with the smallest number of workstations.– Work elements are the smallest units of work that can be performed
independently.– Immediate predecessors are work elements that must be done before
the next element can begin.– Precedence diagram allows one to visualize immediate predecessors
better; work elements are denoted by circles, with the time required to perform the work shown below each circle.
Line Balancing Example 8.3Example 8.3
Green Grass, Inc., a manufacturer of lawn & garden equipment, is designing an assembly line to produce a new fertilizer spreader, the Big Broadcaster. Using the following information, construct a precedence diagram for the Big Broadcaster.
©2007 Pearson Education
Line Balancing Green Grass, IncGreen Grass, Inc..
66
E2020
H
1818
I
4040
D
3030
B
2525
F
5050
C4040
A
1515
G
AA Bolt leg frame to hopperBolt leg frame to hopper 4040 NoneNoneBB Insert impeller shaftInsert impeller shaft 30 30 AACC Attach axleAttach axle 5050 AADD Attach agitatorAttach agitator 4040 BBEE Attach drive wheelAttach drive wheel 66 BBFF Attach free wheelAttach free wheel 2525 CCGG Mount lower postMount lower post 1515 CCHH Attach controlsAttach controls 2020 D, ED, EII Mount nameplateMount nameplate 1818 F, GF, G
TotalTotal 244244
WorkWork Time Time Immediate ImmediateElementElement DescriptionDescription (sec) (sec) Predecessor(s) Predecessor(s)
Desired Output and Cycle Time
• Desired output rate, r must be matched to the staffing or production plan.
Cycle time, c is the maximum time allowed for work on a unit at each station:
1
rc=
Designing Line-Flow Layouts
• Line balancing is the assignment of work to stations in a line so as to achieve the desired output rate with the smallest number of workstations.– Work elements are the smallest units of work that can be performed
independently.– Immediate predecessors are work elements that must be done before
the next element can begin.– Precedence diagram allows one to visualize immediate predecessors
better; work elements are denoted by circles, with the time required to perform the work shown below each circle.
Line Balancing Example 8.3Example 8.3
Green Grass, Inc., a manufacturer of lawn & garden equipment, is designing an assembly line to produce a new fertilizer spreader, the Big Broadcaster. Using the following information, construct a precedence diagram for the Big Broadcaster.
©2007 Pearson Education
Line Balancing Green Grass, IncGreen Grass, Inc..
66
E2020
H
1818
I
4040
D
3030
B
2525
F
5050
C4040
A
1515
G
AA Bolt leg frame to hopperBolt leg frame to hopper 4040 NoneNoneBB Insert impeller shaftInsert impeller shaft 30 30 AACC Attach axleAttach axle 5050 AADD Attach agitatorAttach agitator 4040 BBEE Attach drive wheelAttach drive wheel 66 BBFF Attach free wheelAttach free wheel 2525 CCGG Mount lower postMount lower post 1515 CCHH Attach controlsAttach controls 2020 D, ED, EII Mount nameplateMount nameplate 1818 F, GF, G
TotalTotal 244244
WorkWork Time Time Immediate ImmediateElementElement DescriptionDescription (sec) (sec) Predecessor(s) Predecessor(s)
Theoretical Minimum
Theoretical minimum (TM ) is a benchmark or goal for the smallest number of stations possible, where total time required to assemble each unit (the sum of all work-element standard times) is divided by the cycle time. It must be rounded up
Idle time is the total unproductive time for all stations in the assembly of each unit.
Efficiency (%) is the ratio of productive time to total time.
Balance Delay is the amount by which efficiency falls short of 100%.
Output Rate and Cycle TimeExample.4
Green Grass, Inc. • Desired output rate, r = 2400/week Plant operates 40 hours/week r = 2400/40 = 60 units/hour
Cycle time, c = 1/60
= 1 minute/unit
= 60 seconds/unit
1
r
Calculations for Example.4 continued
Theoretical minimum (TM ) - sum of all work-element standard times divided by the cycle time.
TM = 244 seconds/60 seconds = 4.067 It must be rounded up to 5 stations
Cycle time: c = 1/60 = 1 minute/unit = 60 seconds/unit
Efficiency (%) - ratio of productive time to total time.
Efficiency = [244/5(60)]100 = 81.3%
Balance Delay - amount by which efficiency falls short of 100%.
(100 − 81.3) = 18.7%
Line Balancing Big BroadcasterBig Broadcaster
cc = 60 seconds/unit = 60 seconds/unitTM = 5 stationsTM = 5 stationsEfficiency = 81.3%Efficiency = 81.3%
S1
S2S3
40
66
2020
50
1515
1818
E30
25
4040H
I
D
B
FC
A
G
S1 A A 40 20
S2 B,C C 50 10
S3 B,F,G B 30 30E,F,G F 55 5
Cumm IdleStation Candidate Choice Time Time
©2007 Pearson Education
S1
S2S3
S5S4 66
E2020
H
1818
I
4040
D
3030
B
2525
F
5050
C4040
A
1515
G
Green Grass, Inc. Green Grass, Inc. Line Balancing SolutionLine Balancing Solution
cc = 60 seconds/unit = 60 seconds/unitTM = 5 stationsTM = 5 stationsEfficiency = 81.3%Efficiency = 81.3%
The goal is to cluster the work elements into 5 workstations so that the number of work-stations is minimized, and the cycle time of 60 seconds is not violated. Here we use the trial-and-error method to find a solution, although commercial software packages are also available.
Other Considerations
In addition to balancing a line, managers must also consider four other options:
1. Pacing: The movement of product from one station to the next as soon as the cycle time has elapsed.
2. Behavioral factors of workers.3. Number of models produced: A mixed-model line
produces several items belonging to the same family.
4. Cycle times depend on the desired output rate, and efficiency varies considerably with the cycle time selected.
NL8. En produkt består av 9 st detaljer (D1-D9) vilka monteras ihop enligt strukturennedan:
A
D7
E
D4B
C G
D5
DD8
D1
D2
D3
D6
D9
F
Tiderna för att utföra monteringsoperationerna
är enl. följande:
M1, Delmontering D1, D2 och D3: 12 min
M2, Delmontering D4 och D5: 20 min
M3, Delmontering A och B: 10 min
M4, Delmontering D6 och D7: 8 min
M5, Delmontering D8 och D9: 16 min
M6, Delmontering C och D: 22 min
M7, Slutmontering E och F: 16 min
a) Åskådliggör de olika stegen i monteringen
enligt strukturen i ett precedensdiagram
(nätverk). Kalla monteringsaktiviteterna M1,
M2, ..., M7.
b) Minimera antalet monteringsstationer om
cykeltiden tillåts vara högst 28 min. Använd
"längsta operationstid först"
c) Bestäm balanseringsförlusten.