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Source book: Value-stream Management: eight steps to planning, mapping and sustaining lean improvements, Tapping, Luyster, Shuker,
2002)
Prepared by Dr. ule Itr Satolu 1
What is a value-stream? Manufacturing companies: finished goods
Operations are process elements that add value to the product.
Non-value adding elements
Value stream consists of everything, including non-value adding act.- that makes transformation possible!
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Value-Stream Value-stream similar to a river!
Network of processes and operations through which material and information flows in time and space.
Communication all along the supply chain: information flow.
Material transport & conveyance: material flow.
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Value-Stream Mapping (VSM) Map current state of production showing flow of
material and information.
Goal: To gather accurate and real-time data related to product family or value-stream.
Go to the shopfloor, and collect data. (No past reports etc.).
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VSM To improve a process, you must first observe and
understand it!
Mapping a process: clean picture of wastes!
While gathering data at each point, ask how do we know what to do next? Means of communication.
Trace information and material flow!
Capturing this information is the essence of VSM.
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VSM Icons
(Tapping, Luyster, Shuker, 2002) 6 Prepared by Dr. ule Itr Satolu
Mapping Current State
VSM is drawn for a part/product family!
It is like taking a picture of current state of the shopfloor.
The date VSM is drawn written on the map.
Post current state-map on the story board.
Tool for good visual communication and management!
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Mapping Current State
Visualize entire flow, rather than a single operation
Visualize how currently operations communicate
Sources of wastes
Bottlenecks and WIP
Safety and equipment concerns
Common language for people
See how operation running truly!
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Getting Ready 1. Draw simple sketches of main production
operations on a white board.
2. Go to the floor. Start from the most downstream operation (shipping) and collect actual process data for the key attributes!
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Getting Ready Key Attributes:
Quantity of parts shipped per month and per day
Supplier delivery schedule
Available production time
Cycle time (machine, operators),
Setup time, uptime, OEE.
WIP (between processes)
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Getting Ready Key Attributes:
Number of operators at each process,
Number of shifts
Inventory locations and quantities
Time between processes
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Example Premiere Manufacturing Company
Processes:
Machining, deburring, crimping, testing, marking, shipping
Average demand: 10080 units per month=504 per day.
6720 per month #4 hoses=336 per day
3360 per month #6 hoses=168 per day
Shipping month: 20 days
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Example Units/container: 24
Containers/day: 21
Supplier info: Company recieves a weekly shipment of 2500 units from its supplier ABC.
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Example Process attributes
Shipping Frequency: daily
Finished goods inventory=2000 units
Marking Cycle time=50 sec
Changeover=5 min
Available time=27600 seconds
Uptime ratio=Availability=99%
1 operator
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Example Process attributes
Marking
WIP=2000 units between testing and marking
Time between marking and shipping: 4 days
Similar data collected for Testing, Crimping, Deburring, Machining.
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Example Flow of information and material
All communications with customer & supplier is electronic.
Prod. Control recieves monthly forecasts and weekly orders from customer.
Prod. Control transmits monthly forecasts and weekly orders to the supplier.
Weekly order release to production supervisor.
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Example Flow of information and material
Daily order release to the processes.
All material pushed
FIFO lane between machining and deburring.
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Mapping Current State 1. Draw icons for supplier, customer, production
control (STANDARD icons!).
2. Draw a data label below the customer icon. Enter customer req.s.
3. Enter shipping & receiving data:
Shipping icon below customer icon
Truck icons and delivery frequency
Direction arrows
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Mapping Current State 4. Draw manufacturing processes boxes and label
them: Upstream: left, downstream: right.
Data boxes below each process icon.
Add a notched line (Turkish: entikli izgi) below the process boxes.
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Mapping Current State 5. Enter process attributes into the data boxes for each
process. Show value-added time (cycle time) below each data box, on the notched line.
Write shift time, planned breaks, total available production time into the box, to upper right corner!
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ABC Cord Inc.
MRP
Production
Control
6720 # 43360 # 6
Requirement=10080 /month
part
Weekly
Daily
Shipping
Machining Deburring Crimping
Testing
Marking
45 sec 5 sec 40 sec 30 sec 50 sec
x
x
U
ni
t
45CT= sec
60C/O= min
27600Avail= sec
87Uptime= %
5CT= sec
C/O= min
27600Avail= sec
100Uptime= %
40CT= sec
5C/O= min
27600Avail= sec
99Uptime= %
30CT= sec
5C/O= min
27600Avail= sec
99Uptime= %
50CT= sec
5C/O= min
27600Avail= sec
99Uptime= %
Stats
LT= 34 days
TCT=170 sec
x
x
U
ni
t
x
x
U
ni
t
x
x
U
ni
t
xx Unit
1 shift/day= 8.5 hours
30 min unpaid lunch
Breaks= 20 min
Net Available Time= 460 min.
Per day
336 parts (# 4)
168 parts (#6)
504 parts Total
Steps 1-5:
21 Prepared by Dr. ule Itr Satolu
Attributes Defined Available production time= 460 min= 27600 sec.
Changeover times (C/O) per shift.
Changeover times, not planned downtime (Ex.:3600 sec for machining)
Uptime=Availability= Actual oper. time/Total Available Time
Uptime for machining= (27600-3600) / 27600 = 87%
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Mapping Current State 6. Show information flow, both electronic and manual,
and their frequency.
Draw communication arrows from customer to production control,
Draw arrows from prod. control to supplier.
Draw arrow from prod. control to prod. Supervisor
Draw arrows from supervisor to the processes.
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Daily
Daily
DailyDailyDaily
Weekly
Weekly orders
F/C MonthlyWeekly orders
F/C Monthly
ABC Cord Inc.
MRP
Production
Control
6720 # 43360 # 6
Requirement=10080 /month
part
Weekly
Daily
Shipping
Machining Deburring Crimping
Testing
Marking
45 sec 5 sec 40 sec 30 sec 50 sec
x
x
U
ni
t
45CT= sec
60C/O= min
27600Avail= sec
87Uptime= %
5CT= sec
C/O= min
27600Avail= sec
100Uptime= %
40CT= sec
5C/O= min
27600Avail= sec
99Uptime= %
30CT= sec
5C/O= min
27600Avail= sec
99Uptime= %
50CT= sec
5C/O= min
27600Avail= sec
99Uptime= %
Stats
LT= 34 days
TCT=170 sec
x
x
U
ni
t
x
x
U
ni
t
x
x
U
ni
t
xx Unit
1 shift/day= 8.5 hours
30 min unpaid lunch
Breaks= 20 min
Net Available Time= 460 min.
Production
Supervisor
xx Unit
Per day
336 parts (# 4)
168 parts (#6)
504 parts Total
Step 6:
24 Prepared by Dr. ule Itr Satolu
Mapping Current State 7. Draw inventory icons at the places where
inventory is stored between processes, and
between the most upstream process and supplier,
between the most downstream process and shipping.
Calculate days of inventory (WIP) on hand and write the results on the time line.
Ex: 2000 hoses between testing & marking
2000 hoses / 504 hoses/day=3.96 days or 4 days
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Daily
Daily
DailyDailyDaily
Weekly
Weekly orders
F/C MonthlyWeekly orders
F/C Monthly
ABC Cord Inc.
MRP
Production
Control
6720 # 43360 # 6
Requirement=10080 /month
part
Weekly
Daily
Shipping
Machining Deburring Crimping
Testing
Marking
45 sec 5 sec 40 sec 30 sec 50 sec
10 days
45CT= sec
60C/O= min
27600Avail= sec
87Uptime= %
5CT= sec
C/O= min
27600Avail= sec
100Uptime= %
40CT= sec
5C/O= min
27600Avail= sec
99Uptime= %
30CT= sec
5C/O= min
27600Avail= sec
99Uptime= %
50CT= sec
5C/O= min
27600Avail= sec
99Uptime= %
Stats
LT= 34 days
TCT=170 sec
7 days 4 days 4 days 4 days
1 shift/day= 8.5 hours
30 min unpaid lunch
Breaks= 20 min
Net Available Time= 460 min.
Production
Supervisor
2500
5 days
Per day
336 parts (# 4)
168 parts (#6)
504 parts Total
20003360 #4
1680 #63500 2000
2000
Prepared by Dr. ule Itr Satolu 26
Mapping Current State 8. Draw in push, pull, FIFO locations.
Production based on a schedule: push!
Others: Combinations of pull or FIFO.
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Daily
Daily
DailyDailyDaily
Weekly
Weekly orders
F/C MonthlyWeekly orders
F/C Monthly
ABC Cord Inc.
MRP
Production
Control
6720 # 43360 # 6
Requirement=10080 /month
part
Weekly
Daily
Shipping
Machining Deburring Crimping
Testing
Marking
45 sec 5 sec 40 sec 30 sec 50 sec
10 days
45CT= sec
60C/O= min
27600Avail= sec
87Uptime= %
5CT= sec
C/O= min
27600Avail= sec
100Uptime= %
40CT= sec
5C/O= min
27600Avail= sec
99Uptime= %
30CT= sec
5C/O= min
27600Avail= sec
99Uptime= %
50CT= sec
5C/O= min
27600Avail= sec
99Uptime= %
Stats
LT= 34 days
TCT=170 sec
7 days 4 days 4 days 4 days
1 shift/day= 8.5 hours
30 min unpaid lunch
Breaks= 20 min
Net Available Time= 460 min.
Production
Supervisor
2500
5 days
Per day
336 parts (# 4)
168 parts (#6)
504 parts Total
20003360 #4
1680 #6
3500 2000
2000
Current State Map:
Points to Remember for Current State Mapping
Understand where you are now and decide where you want to go.
Focus on the most accurate information.
Gather actual info- not standard data.
Draw in pencil or on a white board: you will make several changes.
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Lean Metrics Identify the metrics that will help you achieve your
goals. Inventory turns
Days of inventory on hand
WIP
Uptime
Lead time
On-time delivery
Total cycle time
Defective parts per million (PPM)
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Lean Metrics Determine the current values (baseline) for the
identified metrics.
Metric Baseline
Total value stream WIP 17040 units
Total product cycle time 170 seconds
Total value stream lead
time
34 days
On-time delivery 88 %
Defective PPM-external 45
Uptime (=availability) 84 % Prepared by Dr. ule Itr Satolu 31
Lean Metrics Total value-stream lead time=34 days
But total value-added time=170 seconds.
Huge oppurtunity for improvement.
Percent of On-time delivery is 88% due to
Uptime issues in machining process
Shifting production schedules
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Lean Metrics- Example Uptime = Availability=Actual operating time
Available production time
Actual operating time losses: Changeover time, quality problems, late delivery from
upstream, breakdowns, quality problems.
Improvement tech.: Setup time reduction (quick changeover techniques).
Track both internal & external defect rates.
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Discussion to Identify Wastes 10 days of inventory between machining and
deburring- Why?
High changeover times- What is its impact on WIP?
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Mapping the Future State Preparation:
Draw the customer, supplier, production control icons.
Add shipping data.
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Mapping the Future State Stage-1: Focus on Demand
What is the demand? What is the takt time?
Can you meet takt time with current capabilities?
Need buffer stock, safety stock? How much?
Finished goods supermarket?
Other improvement tools?
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Mapping the Future State Stage-1: Focus on Demand
1. Determine the takt-time and pitch for high volume products.
Takt-time = Available production time Required production quantity of the part family
Takt time= 27600 sec / 504 hoses
Takt time= 55 sec per hose
Pitch= Takt time * Pack-out Quantity
Pitch= 55 sec * 24 units/container
Pitch= 1320 sec= 22 min
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Mapping the Future State Stage-1: Focus on Demand
2. Determine if you can meet demand with current capabilities.
Cycle time of line= 50 sec (longest cycle time)
Capacity= 27600 sec 50 sec/part= 552 parts
552 units*0.84=464 units (where uptime of the line=0.84)
464 < 504 units/day.
Actual capacity is less than required capacity.
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Mapping the Future State Stage-1: Focus on Demand
3. Determine if you need buffer and safety inventories.
Buffer: when customer ordering pattern varies.
Safety: when internal constraints or inefficiencies disrupt flow.
Buffer & safety inventories are a hedge against uncertainty.
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Mapping the Future State Stage-1: Focus on Demand
4. Determine if you need a finished goods supermarket
If you are 100% confident in the production system (flow), directly ship from the last process. Otherwise, a supermarket needed.
Maintain certain level of inventory by pull system!
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Mapping the Future State Stage-1: Focus on Demand
5. Determine which improvement techniques to implement!
Quick changeover techniques (QCO):For machining.
Autonomous maintenance (to increase uptime)
5S for workplace organization and standardization.
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Mapping the Future State Stage-2: Focus on Flow
Continuous flow:
Produce only those units needed
When they needed
In exact amounts
1. Perform line balancing: For evenly distributing work elements within a value stream to meet takt time!
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Mapping the Future State Stage-2: Focus on Flow
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Target
# of operators= 170 sec / 55 sec (takt time)= 3.09 operators
# of operators= 150 sec / 55 sec (takt time)= 2.7 operators
* Improve tooling
maintenance and
eliminate the need for
deburring.
* Distribute work of other
3 operations between the
operators.
* Reduce C/O times in
machining to 15 min.
* Achieve C/O time to
Mapping the Future State Stage-2: Focus on Flow
2. Plan for Work cells
Achieving a balanced line depends on applying principles of cell design.
Workers and machines for C,T,M grouped into a cell.
Workers can cooperate.
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Mapping the Future State Stage-2: Focus on Flow
3. Determine how to control upstream production: At points where continuous flow is not achievable, determine how to control flow of prod.
Put supermarkets. Ex.: one between supplier-machining and the other machining-the cell.
Use a kanban system.
Use FIFO lanes.
Use computer assisted scheduling.
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Mapping the Future State Stage-2: Focus on Flow
4. Determine which improvement methods to use
5S, TPM, autonomous maintenance and QCO in manufacturing cell. Why?
Standardized work, QCO, 5S at crimping-testing-marking cell.
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Mapping the Future State Stage-3: Focus on Leveling
1. Decide on paced withdrawal or a Heijunka System, and Design or refine Kanban system.
2. Determine route of the material handler (runner). Map all material and information flow.
3. Determine which improvement methods to use.
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Mapping the Future State Stage-3: Focus on Leveling
It is necessary to create a Kanban system.
24 units per cont.
Containers reusable
Pitch=22 min.=55 sec X 24 units= 1320 sec
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Mapping the Future State Stage-3: Focus on Leveling
Withdrawal Kanban tells runner how many units to be pulled from finished goods supermarket.
Prod. Kanban tells the cell how many units should be replenished.
Signal Kanbans between machining and the cell tell the machining oper. How many units pulled from the supermarket.
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Mapping the Future State Stage-3: Focus on Leveling
Signal Kanbans at the upstream of machining tell supplier how much raw material pulled.
In the Heijunka box,withdrawal Kanbans are put and are visually controlled.
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Future State Map
Takt=55 sec.
Buffer and safety stock in
shipping area.
Pitch=22 min.
U-shaped cell & std. Work
Heijunka & a runner.
Weekly orders
F/C MonthlyWeekly orders
F/C Monthly
ABC Cord Inc.
Production
Control
Weekly
Daily
Shipping
Machining
Crimping/Testing/
Marking
45 sec 105 sec
2 days
45CT= sec
30C/O= min
27600Avail= sec
93Uptime= %
105CT= sec
< 1C/O= min
27600Avail= sec
100Uptime= %Stats
LT= 8 days
TCT=150 sec1 day
1 shift/day= 8.5 hours
30 min unpaid lunch
Breaks= 20 min
Net Available Time= 460
min.
5 days
504 units/day
24 units/
container
Cell
TPM
5S
QCO
5S
Std. Work
VW
5S
55Takt= sec
Pitch=22
VW
S
B
S
1
QCO
5
4
W
2
P 3
Runner
S
Heijunka Box
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Prepared by Dr. ule Itr Satolu 53
(Tapping, Luyster, Shuker, 2002)