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EngineeringManagement
Learning to See Parts I, II, IIIA Value Stream Mapping Workshop
Mike Rother & John ShookLean Enterprise Institute
MSE507Lean Manufacturing
Value Stream MappingWorkshop Goals
To understand the complete value stream To introduce Value Stream Mapping (VSM) To draw a current state map
• Learn the mapping concepts and icons To be able to design an improved value stream
• Develop the ability to “see the flow” of a value stream To draw a future state map
• Learn the mapping concepts and icons
Value Stream MappingTopics
Topic Slide No.• Overview 5• The Process (Steps 1-3) 12• The Process (Step 4 Case Study) 35• The Process (Step 5) 38• The Process (Step 6)• The Process (Step 6 Case Study)• The Process (Steps 7-9)• The Process (Step 10)• Conclusions
Overview
Why? … Learn to See See the big picture, not just individual processes See how the process currently operates See linkages between information and material flow See the waste and the source of waste Establish a common language for improvement Foundation for designing lean flow and the future state
Overview
What do you typically see? 80 – 90% of total steps are waste from standpoint of end
customer 99.9% of throughput time is wasted time Demand becomes more and more erratic as it moves
upstream, imposing major inventory, capacity, and management costs at every level
Quality becomes worse and worse as we move upstream, imposing major costs downstream
Most managers and many production associates expend the majority of their efforts on hand-offs, work-arounds, and logistical complexity
Overview
Objective Correct specification of value Elimination of wasteful steps “Flow where you can” “Pull where you can’t” Management toward perfection
Overview
Pursue Perfection Every step in each process is:
• Capable – right every time (6 Sigma)• Available – always able to run (TPM)• Adequate – with capacity to avoid bottlenecks (right-sized tools &
lean system design)
Overview
What is it? A visual representation of all the steps needed for:
• Concept to launch (design)• Order to delivery (build)• Delivery to recycle (sustain)
All steps:• Value Added (VA)• Non-value added (NVA)
Two flows:• Orders traveling upstream from the customer• Products traveling downstream to the customer
Overview
Who does it? Value Stream Manager
• Ideally, one person with lead responsibility for the entire value stream reporting to the top person at the site
Representatives of every relevant function – operations, purchasing, sales, finance, engineering, etc. (ideally)
And you
When? Now Before any major improvement activity Constantly updated to the new “Future State”
Overview
Where? In the work area itself
How? Directly observe flow of information and physical goods Summarize these flows visually with icons Use pencil and paper
And most important… Envision future state
• No wasted steps• Smooth flow• Level pull
Getting Started
Select one value stream - a product family Walk the physical flow of material – no data collection Walk the flow again, collecting data Draw the Current State Map Identify opportunities to eliminate waste and create flow Draw the Future State Map Generate a Value Stream Plan Start making the improvements Conduct Value Stream Reviews Repeat the cycle
Value Stream Step 1Select a Value Stream
Select one value stream … shared definition of value by customer or customer category by product or product family by plant by service - production, spares, repair
A family is a group of items that pass through similar processing steps and over common equipment.
Focus on the downstream processes not upstream steps. Upstream processes may serve many product families in a batch mode.
Value Stream Step 1 Create a Matrix
1 2 3 4 5 6
A X X X X X
B X X X X X X
C X X X X X
D X X X
E X X X
F X X X X
Pro
duct
s
Assembly and Equipment
A Product Family
Create a matrix if your mix is complicated
Create a MatrixComplicated
Part Part 1 Part 2 Part 3 Part 4 Part 5 Part 6 Part 7 Part 8Machine Weighting
Machine A 2 1 1Machine B 4 1 1 1Machine C 8 1Machine D 16 1 1Machine E 32 1 1Machine F 64 1 1Machine G 128 1 1 1Machine H 256 1 1 1Machine I 512Machine J 1024Machine K 2048Machine L 4096
Part Total 290 80 132 258 88 132 288 132
Weight part by machine used.
0103-02 Family Matrix.xls
Create a MatrixComplicated
Sort by weighted part; Weight machine by part used.
Part Part 2 Part 5 Part 3 Part 6 Part 8 Part 4 Part 7 Part 1Machine
TotalMachine Weighting 32 64 128 256 512 1024 2048 4096 blank
Machine A 2 1 1 5120Machine B 4 1 1 1 896Machine C 8 1 64Machine D 16 1 1 96Machine E 32 1 1 6144Machine F 64 1 1 96Machine G 128 1 1 1 896Machine H 256 1 1 1 7168Machine I 512 0Machine J 1024 0Machine K 2048 0Machine L 4096 0
blank blank 80 88 132 132 132 258 288 290 blank
Create a MatrixComplicated
Sort by weighted machine.
Part Part 2 Part 5 Part 3 Part 6 Part 8 Part 4 Part 7 Part 1Machine
TotalMachine Weighting 32 64 128 256 512 1024 2048 4096 blank
Machine C 8 1 64Machine D 16 1 1 96Machine F 64 1 1 96Machine B 4 1 1 1 896Machine G 128 1 1 1 896Machine A 2 1 1 5120Machine E 32 1 1 6144Machine H 256 1 1 1 7168
blank blank 80 88 132 132 132 258 288 290 blank
Single Plant
(Door-to-door)
Value Stream Step 1Levels of a Value Stream
You can value stream map at different levels
Across companies is too complicated to start with
Process Level
Multiple Plants
Across Companies
Start mapping door-to-door within your own facility:• This is under your control• It is easier to make
improvements immediately Expand outward to broaden the
value stream later
Value Stream Step 2Walk the Flow
Let the workers know what you are doing.
Walk the flow first (no data collection). Walk it yourself.
Begin at shipping and work upstream. This begins with the processes that are linked closer to the customer. If it is too confusing, start at the beginning and go downstream.
See how the material moves.
See the piles of material and WIP.
See how people work.
Identify the major process steps
Value Stream Step 3 Walk the Flow Again
Walk the flow again, this time collecting data.
Begin at shipping and work upstream.
Obtain the data yourself, do not rely on computer printouts. Use pencil and paper.
Ask questions and listen.
Collect data relevant to the definition of value.
Value Stream Step 3 Walk the Flow Again-Typical Data Collected
Customer Need Demand … number of units per day the customer wants Available work time … Scheduled work time minus breaks,
meetings and clean up time
Inventory WIP … Number of units waiting to be worked on or waiting to be
moved. Finished Goods … Number of units in stores or waiting to be
shipped.
Value Stream Step 3 Walk the Flow Again-Typical Data Collected
Each Process Step Cycle time – CT … The time between one part coming off the
process and the next part coming off. Yield … First Time Yield or scrap% Number of people … Required to operate the process. Uptime … The percentage of time the equipment is available to
run, when it is needed to be run Batch Size … typical lot size or minimum Change Over Time – Co … The time from the last good piece
of one batch to the first good piece of the next batch EPE … Every part every __. How often do you changeover to
produce this part?
Value Stream Step 3 Walk the Flow Again-Calculated Data
Takt Time – TT … How often does the customer need another unit.(Available work time per day)/(demand per day)
Inventory … measured in days.(Number of units)/(demand per day)
Overall Flow Process Lead Time … The time for a unit to make it all the way
through the process(Sum of Inventory Days) + (Sum of Cycle Times)
Processing Time … The time spent actually performing work on the unit(Sum of Cycle Times)
Value Stream Step 3 Draw the Current State Map
Drawing the future state map begins with the current production situation.
Symbols and icons assure a consistent language.
Draw the rough draft as you walk the floor in step 3 collecting data.
Use pencil and paper, not a computer.
Map the whole value stream, not just a segment.
PROCESS BOX ICONS
DATA BOX ICONS - C/T time - C/O time - Up time - Scrap
Example
Example
Material Flow
Information Flow
INVENTORY ICONSWITH PUSH ARROWS
Quiz 1Circle the best answer
1. Value Stream Mapping looks atA. The people, materials, and information flow in a value stream
B. The material and information flow in a value stream
C. The detailed operation steps within a cell
D. The steps that people take in designing and producing a product
2. A product family is used to: A. Create a listing of all your products and the steps that are taken to
produce them
B. Decide which customers are most important to your customers
C. Identify and group products into families based upon whether they pass through similar steps in your downstream processes
D. Divide the mapping teams up into groups with individual mapping assignments
Quiz 2Circle the best answer
3. The best way to draw a value stream map is:A. In pencil on the work floor, mapping the whole value stream
B. In your office with a good drawing software package
C. In pencil, by dividing the value stream into segments, and assigning each segment to a different mapping team
D. In pencil, on the floor using standard times from engineering
4. Data boxes should contain data based on: A. Engineering standards
B. The average measurement for a fiscal year
C. The measurement on an ideal day
D. What you observe as you draw the map
Mapping Tips
Use Colored Post-it notes paper for Mapping(Easier to move Post-it notes than redraw)
Use roll of butcher paper so you can use a wall and see the whole VSM
Use string or ribbon to show material & information flows Decide whether to count all parts or sample
Mapping Tips
Best to map production lines betweenTuesday and Thursday
Use someone from the line or process to walk you through it first, post-it note process, come back and getReal Data and Times
If you plan on using the times to balance your process then do not take shortcuts - you will be way off(Embarrass yourself!!)
See with your hands. No “Armchair Lean!”
Mapping Tips
Calculate production lead time for inventory triangles by dividing quantity of inventory by the customer daily requirement• This is a really neat trick! It turns a count of inventory into the
number of production days that inventory represents Add a title and date the map
ACME StampingCase Study
Material Flow Icons
AssemblyXYZ
Corporation
Data Box
C/O=30 min.C/T=45 sec.
3 Shifts.2% Scrap
I300 pieces
1 day
Inventory Supermarket
Shipment Push Finished Goodsto Customer
Physical
FIFO
First-In-First-Out
ProcessBox
Supplier/Customer
Mon + Wed
Pull
Information Flow Icons
ManualInformation Flow
ElectronicInformation Flow
WeeklySchedule
Schedule
OXOX
LoadLeveling Box
Sequenced-PullBall
WithdrawalKanban
ProductionKanban
SignalKanban
KanbanPost
General Icons
Uptime
Changeover
KaizenLightning BurstOperator
Buffer orSafety Stock
“Go See”
Production Schedule
Value Stream Map - Acme Exercise(Use the Handout Data Sheet)
Use a pencil and small Post-it notes on 11” x 17” paper. Use the following colors
• BLUE - Process • YELLOW - Inventory (tear in half) • PINK - Master schedule / Production control • GREEN - Supplier & Customer
Fill in a Post-it notes for each process/data and symbol Remember “Always start with the Customer” Build the map, leave enough room between process boxes to
show inventory and enough space on the bottom to draw the time line
State St. Assembly
18,400 pcs/mo
-12,000 “L”
-6,400 “R”Tray=20 pcs.
2 Shifts
First - Show the Customer
Value Stream Step 4 Current State Map - 1st View
State St. Assembly
18,400 pcs/mo
-12,000 “L”
-6,400 “R”Tray=20 pcs.
2 Shifts
Stamping 4600 L 2400 R
CT=1sec.
Co=1 hr.
Uptime=85%
27,600 sec. avail
EPE=2 weeks
S. Weld # 1
CT=39sec. Co=10 min.
Uptime=100%
2 shifts
27,600 sec.avail
CT=40sec. Co=0
Uptime=100%
2 shifts
27,600 sec.avail
II II
Coils
5 days
CT=46sec. Co=10 min.
Uptime=80%
2 shifts
27,600 sec.avail
CT=62sec. Co=0
Uptime=100%
2 shifts 27,600 sec.avail
ShippingI I
1100L 850 R 640R 600 R
1200 L 1440 R
1600 LS. Weld # 2 Assy # 2Assy # 1
2700 L
Second - add the major Processes, Data Boxes, and Inventory Triangles
The data obtained is put in the data box directly beneath the process box.
Value Stream Step 4 Current State Map - 2nd View
S. Weld # 1 I
2 shifts
27,600 sec.avail
Coils
5 days
1100L 600 R
State St. Assembly
18,400 pcs/mo
-12,000 “L”
-6,400 “R”Tray=20 pcs.
2 Shifts
Stamping
4600 L 2400 R
CT=1sec.
Co=1 hr.
Uptime=85%
27,600 sec. avail
EPE=2 weeks
CT=39sec. Co=10 min.
Uptime=100%
CT=40sec. Co=0
Uptime=100%
2 shifts
27,600 sec.avail
II II
CT=46sec. Co=10 min.
Uptime=80%
2 shifts
27,600 sec.avail
CT=62sec. Co=0
Uptime=100%
2 shifts 27,600 sec.avail
ShippingI
850 R 640R 1200 L
1440 R 1600 L
S. Weld # 2 Assy # 2Assy # 1
2700 L
1XDaily
Michigan
Steel Co.
Tues &Thurs.
500 Ft. Coils
Third - Show the Material Flow
A truck icon and broad arrow indicate movement of finished goods to the customer and raw material to the site.
The supplier of raw material is identified with a factory icon. In this case they deliver 500 ft coils
Value Stream Step 4 Current State Map - 3rd View
Value Stream Step 4 Current State Map
Information flow is drawn from right to left in the top half of the map space.• solid line arrows (paper transfer)• arrow with a lightening bolt (electronic transfer)
Material movements that are pushed are represented by a striped arrow
PUSH• A process that produces regardless of the needs of the
downstream customer• A guess as to what is needed (forecasts)• Processes are allowed to set batch sizes and produce at a pace
that makes sense from its perspective not the customers.
State St. Assembly
18,400 pcs/mo
-12,000 “L”
-6,400 “R”Tray=20 pcs.
2 Shifts
Stamping
4600 L 2400 R
CT=1sec.
Co=1 hr.
Uptime=85%
27,600 sec. avail
EPE=2 weeks
S. Weld # 1
CT=39sec. Co=10 min.
Uptime=100%
2 shifts
27,600 sec.avail
CT=40sec. Co=0
Uptime=100%
2 shifts
27,600 sec.avail
I
I
II
Coils5 days
CT=46sec. Co=10 min.
Uptime=80%
2 shifts
27,600 sec.avail
CT=62sec. Co=0
Uptime=100%
2 shifts 27,600 sec.avail
ShippingI
I 1100R
850 R 640R 600 R 1200 L 1440 R
1600 L
S. Weld # 2 Assy # 2Assy # 1
2700 L
1XDaily
90/60/30 dayForecasts
DailyOrder
ProductionControl
MRP
6 WEEKForecast
Michigan
Steel Co.Weekly
Fax
Tues &Thurs.
WEEKLY SCHEDULE500 ft. Coils
Fourth - show Information Flows & Push Arrows
Value Stream Step 4 Current State Map – 4th View
Value Stream Step 4 Current State Map
The timeline summarizes the current condition of the value stream
Production Lead-Time is the time it takes for a part to make its way through the shop floor beginning with the raw material
Inventory Lead-time( shown with the inventory triangles)is calculated as follows:
• Inventory quantity divided by the daily customer requirements. Then add all process inventory lead-times.
Inventory Quantity
Daily Customer Requirement
State St. Assembly
18,400 pcs/mo
-12,000 “L”
-6,400 “R”Tray=20 pcs.
2 Shifts
Stamping
4600 L 2400 R
CT=1sec.
Co=1 hr.
Uptime=85%
27,600 sec. avail
EPE=2 weeks
S. Weld # 1
CT=39sec. Co=10 min.
Uptime=100%
2 shifts
27,600 sec.avail
CT=40sec. Co=0
Uptime=100%
2 shifts
27,600 sec.avail
I
I
II
Coils5 days
CT=46sec. Co=10 min.
Uptime=80%
2 shifts
27,600 sec.avail
CT=62sec. Co=0
Uptime=100%
2 shifts 27,600 sec.avail
ShippingI
I 1100R
850 R 640R 600 R 1200 L 1440 R
1600 L
S. Weld # 2 Assy # 2Assy # 1
2700 L
1XDaily
90/60/30 dayForecasts
DailyOrder
ProductionControl
MRP
6 WEEKForecast
Michigan
Steel Co.
Weekly
Fax
Tues &Thurs.
WEEKLY SCHEDULE500 ft. Coils
5 days
1 sec
7.6 days
39 sec
1.8 days
46 sec
2.7 days
62 sec
2 days
40 sec
4.5 days=23.6 days
=188 sec
(PLT)
(PT)
Fifth (Final) - Show Timeline
Value Stream Step 4 Current State Map – 5th View
State St. Assembly
18,400 pcs/mo
-12,000 “L”
-6,400 “R”Tray=20 pcs.
2 Shifts
Stamping
4600 L 2400 R
CT=1sec.
Co=1 hr.
Uptime=85%
27,600 sec. avail
EPE=2 weeks
S. Weld # 1
CT=39sec. Co=10 min.
Uptime=100%
2 shifts
27,600 sec.avail
CT=40sec. Co=0
Uptime=100%
2 shifts
27,600 sec.avail
I
I
II
Coils5 days
CT=46sec. Co=10 min.
Uptime=80%
2 shifts
27,600 sec.avail
CT=62sec. Co=0
Uptime=100%
2 shifts 27,600 sec.avail
ShippingI
I 1100R
850 R 640R 600 R 1200 L 1440 R
1600 L
S. Weld # 2 Assy # 2Assy # 1
2700 L
1XDaily
90/60/30 dayForecasts
DailyOrder
ProductionControl
MRP
6 WEEKForecast
Michigan
Steel Co.
Weekly
Fax
Tues &Thurs.
WEEKLY SCHEDULE500 ft. Coils
5 days
1 sec
7.6 days
39 sec
1.8 days
46 sec
2.7 days
62 sec
2 days
40 sec
4.5 days=23.6 days
=188 sec
(PLT)
(PT)
Fifth (Final) - Show Timeline
Value Stream Step 4 Current State Map – Complete View
What’s wrong with Acme’s Value Stream?
3 VA processes Traditional mass
production thinking about economies of scale
Batches pushed through => waste
Look at VA time compared to time in plant
What Makes a Value Stream Lean?
Primarily the elimination of the number one waste…
OVERPRODUCTION!!!
Since this material is not yet needed it must be handled, counted, stored.
Defects remain hidden in inventory queues
Overproduction results in shortages, because processes are busy making the wrong things.
1. Overproduction
2. Waiting
3. Transportation
4. Unnecessary Processing
5. Inventory
6. Unnecessary Motion
7. Correction
Wasting A Person’s time or talent
Value Stream Step 5 Eliminate Waste
Value Stream Step 5 Eliminate Waste
1. Overproduction - The primary waste• Making parts faster than is required
• Excess Inventory• Time wasted, that could be used to make product that is
required
2. Waiting• An operator waiting for a long machine cycle to end
3. Transportation• Moving parts and products does not add value - it just adds cost
Value Stream Step 5 Eliminate Waste
4. Unnecessary Processing• Booking work into a store and then having to book it back out
again to use.
5. Inventory• There is a cost to the Company for carry inventory• There is always the risk it can become obsolete• It covers up other inefficiencies
e.g. Long set-up times
Value Stream Step 5 Eliminate Waste
6. Unnecessary Motion• Any motion of a person that does not add value
• Operators / Setters looking for tooling
7. Correction• Reworking defective materials
Things to remember about waste• It is a symptom rather than a root cause of the problem• It points to problems within the system, at both process and value
stream levels• We need to find and address the causes of the waste
Value Stream Step 5 …And Create Flow
We are concerned with system efficiency rather than the efficiency of an individual process
The question is, how fast should we produce?
Value Stream Step 5 Takt Time
We should match the rate of production to the rate of sales
Takt is the German word that means “beat” or “pace”
Takt Time = Effective working time per day Customer requirement per day
= 27,000 sec = 59 sec 460 pieces
• What is the effective working time per day?• What do we do about machine down time?• Why is cycling faster than takt expensive?
Value Stream Step 5 What is Flow?
Value Stream Step 5 Where Do We Use Flow?
Use continuous flow wherever possible
Where can’t we use continuous flow? Long set-ups Large distances Downtime problems Long lead-times
Value Stream Step 5 Alternatives to Continuous Flow
Kanban A signal that provides an instruction to regulate the sequence and
timing of production Two-bin
Bins used to regulate production Buffer stock
Standard work Curtain operation
Supermarket Controlled quantity of inventory Visual controls Owned by the supplier
Value Stream Step 5 Supermarket Pull System
A SUPERMARKET PULL SYSTEM
SupplyingProcess
A
CustomerProcess
BPRODUCT
Supermarket
Production KANBAN Withdrawal KANBAN
1) CUSTOMER
PURPOSE: Controls production at supplying process without trying to schedule. Controls production between flows
Value Stream Step 5 Supermarket Pull System
A pull system between processes…• gives accurate build instructions to the upstream process• without trying to predict downstream demand• instead of forecasting the upstream process.
The pull by the downstream process determines• what the upstream produces• when• and in what quantity.
Should be located near the supplying process
Are only used when continuous flow will not work.
There is a cost - inventory and material handling
If pull systems schedule upstream process we can try to schedule only one point in the value stream - Pacemaker
No supermarkets downstream of the schedule point(except finished goods)
Value Stream Step 5 Schedule Only One Point
schedule
schedule
Quiz 3Circle the best answer
5. Takt time is:A. The customer demand rate
B. The rate at which the Sales departments plan to sell products to customers based upon promotions
C. The fastest rate at which your individual operations can produce the products
D. The average amount of product brought by your customers in a week
6. A supermarket is used where: A. Processes are close together but have different cycle times
B. A customer requires specialised products from a finished goods warehouse
C. Continuous flow is not possible due to distance, unreliability, or where processes serve multiple product families
D. Pull can be implemented throughout the door-to-door value stream
Quiz 4Circle the best answer
7. A pacemaker process:A. Ensures that all processes downstream are controlled by supermarket pull
systems
B. Receives its products from supermarkets controlled by MRP systems
C. Is always a bottleneck, requiring constant supervision and staff adjustment
D. Responds to the external customer, and is usually the point at which production is scheduled in the door-to-door value stream
Homework Assignment Questions:
1. Describe the ways a business could use Value-stream mapping. What will be the benefits?
2. You are visiting a production plant that has achieved excellence and is a model site to bench mark in the industry. List what you are likely to see when visiting a lean plant? How will their current Value Stream might look like?
Read Leaning to See Parts IV and V
• Pages 57-101
Questions? Comments?