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alue stream mapping (VSM)can be an extremely powerfultool, combining material pro-
cessing steps with information flow aswell as other important related data.VSM is arguably one of the most pow-erful lean tools for an organizationwanting to plan, implement andimprove on its lean journey. This toolallows users to create a solid imple-mentation plan that will make themost of their available resources.
For a lean journey, think of VSM asthe launch pad to begin identifyingand improving a process family. VSMis about sparking change—declutter-ing the process of the nonessentialactivities that don’t add value butwaste time and resources.
VSM, as it is known today, stemsfrom Toyota Motor Co.’s material andinformation flow diagrams.1, 2 In itsmost basic form, VSM shows the
process steps from order entry todelivery.
The value stream in VSM is thepoint at which value is actually addedto the product or service by changing
the market form or function to meetthe customer’s needs. For example,value adding activities can be thingslike: machining, assembly, welding,drilling, folding, painting and so on. Ifyou are not adding value, you areprobably adding muda, (the Japaneseword for waste).
Pictorial representations of VSM are
easy ways to learn a language thatanyone in your organization canunderstand—a key element whencommunicating with process maps.Building a VSM offers detail that goesbeyond the amount of informationyou can relay with any standard flow-chart.
Value Stream Scope
Understanding the scope of thevalue stream under examination is animportant place to start the VSM task.Think of the scope as the door to doorprocess for a facility level map. Adepartmental or interdepartmentalpractice is considered a process levelmap. When multiple plants, cus-tomers or suppliers are included, anextended level map is created.
Consider an extended level map asthe view of the values stream at 60,000feet, the facility level map at 30,000
64 I JUNE 2006 I www.asq.org
Value Stream Mapping—an Introductionby Tony Manos
V
LEAN LESSONS
A tool that combines material processingsteps, information flow.
Process Family Matrix ExampleFIGURE 1
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Name150 80,000 lb/mo X X X X X X X X X X X 1 Coil to coilORM005 80,000 lb/mo X X X X X X X X X X X 1 Coil to coil020 AI GLD 5,000 pcs/mo X X X X X X X X X X X X X 2 Ornamental020 AI Stuco 1,000 pcs/mo X X X X X X X X X X X X X 2 Ornamental73518 400 pcs/mo X X X X X X X X X X X X X X X 3 Fab flatBallast 300,000 lb/mo X X X X X X 4 BallastNordham 100 pcs/yr X X X X X X X 5 Pass through611402401 250 pcs/mo X X X X X X X X X X X X X X X 6 Fab formVT4880 50 pcs/mo X X X X X X X X X X X X X X X 6 Fab formEAW435? 150 pcs/mo X X X X X X X X X X X X X X X X 6 Fab formYNG Filter 25 pcs/mo X X X X X X X X X X X X X X X 6 Fab formGehl 001 150 pcs/mo X X X X X X X X X X X X X X X 6 Fab form509566 700 pcs/mo X X X X X X X X X X X X 7 Coil to sheet to size601 250 pcs/mo X X X X X X X X X X X X X 7 Coil to sheet to size020 AI MF 8,000 pcs/mo X X X X X X X X X X X X 8 Coil to blankNailor 500 pcs/mo X X X X X X X X X X X X X 8 Coil to blank202262 20,000 pcs/mo X X X X X X X X X X X X XStock Plate 250,000 lb/mo X X X X X X X X X X X X 9 Stock plate
feet and the process level map at10,000 feet.
It is best to start at diagramming afacility level map before attempting todraw a process level map or extendedlevel map so you do not optimize onearea and suboptimize another. Thiscolumn will focus on the facility levelmap.
Ready a Team for the Event
The best—and probably easiest—way to create a VSM is to form a crossfunctional team that includes supervi-sory or managerial level membersfrom throughout the organization.
Representatives from departmentslike sales, customer service, schedul-ing, purchasing, operations, inventorycontrol, maintenance, quality andinformation technology can be valu-able contributors to this part of theVSM journey. Even customers or sup-pliers—both internal or external—addunique perspectives.
Be aware of the actual size of this
team and how it can affect decisionmaking and action. A good team sizeis usually between seven and 10members. This size makes it easier formembers to conduct interviews and“walk the flow,” that is, actually visit-ing each of the work areas affected bythe process evaluation and includedin the VSM to see firsthand howthings work or don’t work.
Predictably, the larger the team, themore difficult it may be to manage. Ifthe team has fewer than seven mem-bers, there may not be enough voicesto provide well-rounded input.
Finally, never create a map with ateam of one. You will not get enoughvaluable input or cross functional dia-logue or the results may be biased forone area, person or department.
Kaizen Kick-Off
Once the team is formed, a threeday kaizen (Japanese for “change forthe better”) event, as seen in Table 1,is usually enough time to create thecurrent state and future state maps,along with the draft plan (more detailon these deliverables is highlightedlater). More time may be needed to
QUALITY PROGRESS I JUNE 2006 I 65
Common VSM IconsFIGURE 2
VA
NVA
Value added time
Nonvalue added time
Inventory or queue time
Cycle or process time
Office
Warehouse
Customers/suppliers
Person
Go see
Information flow
Material flow
Kanban?route
HardcopyElectronic
Movement
Push
Truck -deliveries/shipments
Kanbans?arrivingin groups
Withdrawal (move) Kanban
Production (make)Kanban
Supplier (batching) Kanban
Queue/waitingQ
= Number of people/shift
Office/support data box P/T = Processing time Diff = Difficulty (1-5) C/O = Changeover A&C = Accurate & Complete Prior = Prioritize Rel. = Reliability Qty = Quantity per ____
Office
Software
Department/work center
Withdrawal
Supermarket
OXOX
- FIFO -Maximum
(First-in, first-out)
Heijunka(Level loading)
InventoryI
= Number of people/shift
Manufacturing/shop C/T = Cycle time M/T = Machine time C/O = Changeover FPY = First pass yield Rel. = Reliability Qty = Quantity per ____
Kaizen?burst/improvement
Expd = Expediting costs
Supplier/Outside processing Dist = Distance Qty = Quantity FPY = First pass yield OTD = On-time delivery Serv = Service level
Loop
Typical Three-Day VSM Kaizen Event AgendaTABLE 1
Day 1 Day 2 Day 3• Introduce VSM.• Determine process
families.• Walk the flow and
gather information.
• Draw the current statemap.
• Perform lean conceptstraining.
• Create the future statemap.
• Develop the draft plan.
complete the detailed draft plan anddetermine the resources required toimplement the lean ideas. It is impor-tant to designate an individual withprevious experience in VSM to facili-tate this kaizen event.
At the kaizen event, the team mustcomplete four important steps toprogress through VSM:
• Determine the process family.• Draw the current state map.• Determine and draw the future
state map.• Draft a plan to arrive at the future
state.
Process Family
A process family, also known as aproduct family, is a group of productsor services that go through the sameor similar processing steps. To deter-mine your process family, create amatrix similar to the example shownin Figure 1 (p. 64).
• Along the top row, write all theprocess steps your organizationperforms from a 30,000-foot pointof view.
• In the first column, write down
the parts (for example, compo-nents, stock keeping units, fin-ished good items or services) yourorganization makes or provides.
• Place an X in the correspondingbox if the part goes through theprocessing step.
Many cross functional teams skipthis step in the process. A team maydecide this step seems unnecessary.The team may mistakenly believe ithas already identified the valuestreams, or it may consider this steptoo difficult or complicated to per-form.
I must emphasize this point again:Do not skip this step. Building aprocess family matrix can save youmuch time in the future and helpavert headaches down the line. Takingthis step will help everyone under-stand the value streams and wherethey are in the process.
For example, one company claimedit had a very simple process and theteam elected not to perform this step.There were many process steps theteam didn’t consider and steps not inthe main flow, so these parts were not
included in the original matrix. Aftercloser examination, the team thatthought its company had only oneprocess family actually had nine fami-lies.
After completing this vital step,examine the matrix and look for partsthat go through similar or the exactsame processing steps. Search foritems or parts that share about 80% ofthe steps. Look for items or parts thatwould make sense if they were createdalongside each other in a manufactur-ing cell. In other words, consider itemsor parts that share many of the samesteps and procedures that can be creat-ed together—by the same workersusing similar or related steps—moreefficiently in a manufacturing cell.
At this point, the team must selectthe particular process family it willconcentrate on for the current statemap.
Every organization may have a dif-ferent reason for selecting one processfamily over another when decidingwhich map to draw first or whichorder it should map out its valuestreams. Here are some criteria the
66 I JUNE 2006 I www.asq.org
LEAN LESSONS
VSM Current State Map ExampleFIGURE 3
VSM team may use to decide whichprocess family to draw:
• Biggest bang for the buck.• Largest reduction in lead time or
inventory.• Biggest impact to the customer.• Highest probability for success.• Most visible to stakeholders.• New product line.• Volume or quantity.
Plotting the Current State
The current state map should illus-trate how your organization’s process-es perform in today’s work envi-ronment. To create a current state map,collect the data and information bywalking the flow and interviewing thepeople who perform the task. Thereare two main reasons why walking theflow is more beneficial to creating themap than staying seated at your deskin front of the computer:
• The team will have the opportuni-ty to see the entire process andlook for waste.
• Value-adders—the people whoactually perform the work (opera-tors, assemblers, technicians,
etc.)—can answer questions andclarify any misconceptions or pre-conceived notions on how tasksare performed.
From walking the flow, the teamcan collect on a worksheet severaltypes of information, such as:
• Cycle time or processing time.• Changeover time.• Reliability of equipment.• First pass yield.• Quantities.• Number of operators and shifts.• Hardcopy information.• Electronic information.• Inventory levels.• Queue or waiting times.There’s a rule of thumb to help the
team: If the information is in the ball-park then it can be used to get started.For example, if an operator says hermachine breaks down about fourhours every week, the team can markdown 90% for reliability (of equip-ment). If it’s discovered later the actu-al reliability was 91%, that differencewouldn’t have that much of animpact. Ninety percent was badenough for the team to know some
changes were necessary. You do nothave to wait for perfect data (analysisparalysis), but wrong or disinforma-tion needs to be clarified. If you are indoubt about any of the data, then con-sider measuring it to verify.
Pencil And Paper
With the information gathered fromwalking the flow and the ensuingteam discussions, it’s now time tosharpen the pencil and put the lead topaper. Any VSM can be drawn usingsimple symbols or icons, some ofwhich are shown in Figure 2 (p. 65).
Once the information has been col-lected, I recommend drawing the mapon 11 by 17 paper (landscape) usingpencil and—probably a large eraser.Key areas on the map are:
• The upper right corner for cus-tomer information.
• The upper left corner for supplierinformation.
• The top half of the paper for infor-mation flow.
• The bottom half for material (orproduct) flow.
• The gutters on top and bottom to
QUALITY PROGRESS I JUNE 2006 I 67
VSM Future State Map ExampleFIGURE 4
calculate value added and nonval-ue added time.
Calculate the cycle time vs. theinventory time (in days) for the mater-ial and information flow. Every VSMwill look slightly different dependingon the exact process, the author whodrew the map and how it was drawn.See Figure 3 (p. 66) for an example ofa VSM current state map used for ametal fabricating company.
If this is one of your first VSMkaizens, have the experienced facilita-tor draw the map on a large dry-eraseboard and the team members draweach of their own maps on paper. Ifyour team members are more experi-enced, they may gather the data firstand then draw the map. If they areexperts they may just draw the map asthey gather the data. The current statemap is usually completed by the sec-ond day, but it needs to be refined alittle the next morning. Remember,
when drawing your maps, your eraseris your best friend.
Future State Map
Once the current state map is com-plete, the team can set its sights on cre-ating the future state map. Make surethe team members have some basictraining on lean principles to develop arealistic future state map (see Figure 4,p. 67). Different authors will suggestquestions to guide you to a futurestate. Be careful to use the questionsappropriate to your type of business.Here is a short list of questions withcommon elements that may fit mosttypes of business:
• What is the takt time? Takt is theGerman word for the baton a con-ductor uses to control his orches-tra’s speed, beat and timing. Takttime refers to how frequently apart or component must be pro-duced to meet your customers’
demand. The formula is the timeavailable (per shift) divided by thedemand (per shift). For example:
22,000 seconds (time available) ÷ 200 pieces (demand) = 110 seconds/piece.
• Are there bottlenecks or con-straints? From the data collectionduring the kaizen, look at the cycletimes or processing times. If any ofthese are greater than your takttime, you have a candidate for abottleneck or constraint. This maybe causing overproduction wasteor work in process (WIP) in someareas or extra processing time,such as overtime, to meet demand.
• Where can inventory (or queuetime) be reduced or supermarketsused? Look at raw material, WIP,buffer stock, safety stock and fin-ished goods inventories to see
68 I JUNE 2006 I www.asq.org
LEAN LESSONS
Project: Value Stream Mapping
10%
30%60%
PercentagecompleteStatus Goals and objectives Location/facility: Promedica - North Campus Lab
Process family: Chem Line AutomaticValue stream manager: Eileen Allott
Date reviewed:NOTE: Update value stream map
N = Not started 2 20%Reduce lead-time by 50%Reduce inventory by 50%
Improve teamwork
I = In-progress 4 40%C = Closed 4 40%
Total: 10
ID
Stat
us
Loop
Effo
rt
Impa
ct
Prio
rity
Description Start date End date Leader Team Comments
1 C 1 L H 1 5S kaizen in assembly area XX/XX/XX XX/XX/XX Tom Improved safety
2 I 1 L L 3 QCO on press #31 XX/XX/XX XX/XX/XX Joanne Waiting for parts
3 C 1 L M 2 Poka-yoke the assemblyprocess XX/XX/XX XX/XX/XX Bob No errors
4 C 2 L H 1 Create standardize work inassembly XX/XX/XX XX/XX/XX George Reduce cycle time
by three minutes
5 C 2 M L 3 Redux=ce batch size by 50% XX/XX/XX XX/XX/XX Ralph Improved flow, nolate deliveries
6 I 3 M M 2 Eliminate paperwork in orderentry XX/XX/XX XX/XX/XX Jennifer Need help from IT
7 I 3 M H 2 Improve FPY on part family#502 XX/XX/XX XX/XX/XX Homer SSBB leading
project
8 I 3 H L 3 Perform TPM event toimprove reliability of WC #12 XX/XX/XX XX/XX/XX Bart In progress this
week
9 N 4 H M 3 Create assembly cell XX/XX/XX XX/XX/XX Marge Not started
10 N 5 H H 2 Set up kanban/supermarketpull system XX/XX/XX XX/XX/XX John Not started
Example of a VSM PlanFIGURE 5
whether these can be reduced. Doesit make sense to put in a supermar-ket replenishment system? A supermarket is a controlled
inventory system—the down-stream process removes itemsfrom the shelf and the processowners upstream replenish thatamount to the supermarket.The key is to find ways to reduce
inventory in a logical manner.Also look for opportunities forpaperwork to flow and not sitaround, like in batching.
• Where can you improve flow? Is itpossible to put materials into a cellor eliminate materials from stop-ping and waiting? If flow improve-ment isn’t possible, could a first in,first out lane be establishedbetween processes?
• What other improvements arerequired? For instance, does thereliability of equipment need to beimproved? Are the first pass yieldor quality levels acceptable? Dowe need to perform training in 5S(workplace organization)? Do weneed to create a new layout for anarea?
On the map, place a kaizen burst (seeFigure 2, p. 65) around any items tosignal improvement is needed. Itemsmay include low equipment reliabilityor first pass yield, long changeovertimes, large batches, any waste such asoverproduction, motion, transporta-tion, waiting, defects or adjustments,and over or extra processing.
If you are not sure whether thereneeds to be an improvement duringthis timeframe, put a kaizen burstaround it anyway. You can determineif it will be a priority when you puttogether your plan.
From the answers to these and otherquestions related to the process, youwill be able to draw a future statemap that reflects how you want youroperations to be based in six or 12months, as shown in the example inFigure 4 (p. 67).
Estimate the amount of inventoryand queue times based on improve-ments that are achievable. Recalculatethe value added vs. nonvalue addedtime on the sawtooth line.
Draft Plan
Creating (and executing) the draft
plan is the most important part ofVSM. Creating the maps can be anenlightening experience. But if you donot execute the plan, you have justcreated more muda.
During a typical VSM event, it ispossible to create the draft plan basedon the information from the futurestate map. The plan will need furtherrefinement—especially in determin-ing resources required, such as time,people and budgets. A good plan, asshown in the example in Figure 5, willinclude the description of the project,name of the project leader, possibleteam members, a schedule (or Ganttchart) of events and deliverables, anestimate of costs and the impact, goalsor benefits.
VSM can be an effective tool tobuild improvements and efficienciesfor any organization. For completingthis part of the lean journey, the pay-offs can be immense for any organiza-tion. VSM requires a dedicated teamready to ask difficult questions andthink beyond the current state—and ateam not afraid to admit error and usethat eraser a few times along the way.
REFERENCES
1. Mike Rother, John Shook and Jim Womack,Learning to See, Mellon’s Books, 1999.
2. Jeffrey Liker, The Toyota Way, McGraw-Hill,2004.
BIBLIOGRAPHY
Keyte, Beau, and Drew Locher, TheComplete Lean Enterprise: Value StreamMapping for Administrative and OfficeProcesses, Productivity Press, 2004.
ANTHONY MANOS is a catalyst withProfero, Inc., a lean consulting, training andimplementation firm. He is a senior member ofASQ, an instructor for ASQ’s course on LeanEnterprise and Kaizen and is the current chairof the Lean Enterprise Forum. Tony has anMBA from the University of Illinois-Chicago.
QUALITY PROGRESS I JUNE 2006 I 69
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