Chapter 5
Value Stream Mapping
5 Principles of LEAN
1) The definition of value is from the customer perspective
2) Value stream mapping- mapping information flow and
product/service transformation
3) Continuous flow- having everything ready internally as needed for
a symphony of service or production
4) Pull production- providing only when needed
5) Strive for perfection- never giving up the chase for perfection.
Mapping the value stream
• Following the product or product family
from beginning to end (really from end to
beginning).
– Each value-added and non-value added step
is noted and timed
What does value added mean?
What is value added?
• Value added (VA) activities are those that customer is
willing to pay for. (Also called customer value-added
CVA). They transform the product service or transaction
in a way that is meaningful to the customer.
Examples?
• Non-value-added (NVA) are all those activities required by
a business to execute work that adds no value from a
customer point of view and that customers are not willing
to pay for.
Examples?
Should all NVA steps be
eliminated?
• What about:
– Equipment maintenance?
– Janitor service?
– Payroll? Internal audit? Budget forecasting…
• These don’t add-value to the customer, but are
necessary for the functioning of the business.
• So really there are 3 types of steps in a value stream:
1. Steps that create value
2. Steps that create no value but are necessary
3. Steps that create no value and therefore can be eliminated.
Traditional vs. Waste
elimination approach
Total lead-time through Value Stream
Muda (waste) and non value added activities.
Traditional improvement focus
Muda (waste) and non value added activities.
Value
Added
Make value
added twice as
fast
Value
Added
Waste elimination focus
Reduce wasted
time
Muda (waste) and non
value added activities.
Value Added
So what is Value Stream
Mapping?
• Value stream mapping is a tool that helps
you see and understand the flow of material
and information as a product/service makes
its way through the value stream.
– Usually a pencil and paper process at first.
– Carefully draw a visual representation of
every process in the material and
information flow.
– Then ask a set of key questions and draw a
“future state” map of how value should flow.
Why is VSM an essential tool?
“The real voyage of discovery consists
not in making new landscapes but in
having new eyes.”
–Marcel Proust (1871-1922), Novelist
• Helps you visualize more than just the single-process level, you can
see the whole flow.
• Helps you see more than waste, and identify the sources of waste.
• Makes decisions about the flow apparent
• It forms the basis of an implementation plan. Value stream maps
become a blueprint for lean implementation.
• Show the link between the information flow and the material flow.
• Is a qualitative and quantitative tool by which you describe in detail
how your facility should operate in order to create flow.
Phases in VSM
1
2
3
4
• Identify product or product family to map
• Should share similar downstream “assembly” steps and equipment.
• Current state drawing
• Future State Drawing
• Plan and implementation
Mapping the Current State
•
•
•
•
•
Draw by hand and pencil
Try to collect current information
Check for integrity of the data
Start at the end and work upstream
Bring your stopwatch to perform needed or
missing time and motion studies
• Do the value stream yourself (walk the floor)
• Should be one person
• Map material & information flows
Production flow
Production System
Definition
Consequences
PUSH
Builds to plan regardless
of customer demand.
Overproduction or
shortages that don’t
meet the actual needs of
the customer.
PULL
Driven by actual
consumption and
controlled by
synchronized
replenishment.
Removes inventory
(waste) allows flexibility,
WIP, handling, quality
errors, defects, and lead
time.
After Value Stream mapping the next step LEAN step is
flow. Flow produces a product without unnecessary
interruption or delay.
Key concept…Takt Time
• “Pace” of customer demand
Pr oduction Time Available
Takt Time 
Customer Demand
•
*Minus lunch breaks, briefings, other…
• Can also apply to transactions, services, or parts
• Can be defined in terms of per day, month, or other metric.
• Creates a sense of urgency, without it everyone will produce at their
own schedule.
• As soon as the customer demand is determined, the organization
must make the commitment to meet it.
Takt Time Example
• Customer demand is 100 widget’s/ day
• Production time available/day = 8 hours – 480 minutes
– Lunch – 45 minutes/day
– Breaks – 30 minutes
480  75
Takt Time 
 4.05 min/ part
100
TAKT TIME= In order to meet customer demand within available work
time, we must produce a widget every 4.05 minutes.
– If product is grouped, or batched then we can calculate Pitch Time
PitchTime = Takt Time * batch size
– If demand can’t be met with current resources and processes, Lean
tools such as Buffer or Safety resources should be used.
Creating a map…
Common VSM Symbols
• There is some variation between
software and companies. But on a
whole very similar.(Book lists them
on page 97.)
• Typical Process data/ form:
Process
C/T=
Cycle Time
P/T=
Production time
CO=
Changeover time
U/T-%SHFs=
Uptime
Chart from: http://www.edrawsoft.com/Value-Added-Flow-Chart.php
Example:
Scorpion PB&J Factory
• Daily demand of 700 pieces
• With the following factory arrangement.
– Hours per shift: 8
– Break minutes per shift: 30
– Shifts per day: 1
– Days per week: 5
CALCULATE: TAKT TIME
Get out your pencil and a (big) piece of paper
Example from http://lssacademy.com/2008/02/24/lets-create-a-current-state-value-stream-map/
Start the map with the customer
Draw in the customer box /
details. In the top right hand
side of the paper we draw the
little saw topped box
representing our customer.
We also note their monthly
and/or daily demand along with
the takt time as calculated in
step 1.
Material Flow
PROCESS: What would be the general steps needed?
define the start and stop point of the process.
• Peanut butter Application – 1 operator - 25 second cycle
time
• Jelly Application – 1 operator – 30 second cycle time
• Packaging- 1 operator – 42 second cycle time
• Shipping
Focus on the material flow first
Start at the END of the process
and begin drawing the map back
to front.
Focus on the material flow first.
Focus on the material flow side of
things first (bottom portion of the
map). This includes the process
boxes and data boxes.
Inventory
•
•
•
•
Before PB Application – 700 pieces
Before Jelly Application – 359 pieces
Before Packaging – 486 pieces
Before Shipping – 128 pieces
(In our example, we chose to simply count two pieces of bread as one
subassembly since they move together down the production line.
Also, we are not accounting for the peanut butter and jelly “raw
material” at this point. )
• During the walk through of the process we noticed that each process
step seemed to be working in isolation. In other words, the lady
working at the peanut butter application seemed to produce as many
units as she could and then pushed them along to the jelly
application process.
Add the Inventory/Wait Times.
Once you have all the process
and data boxes in, it’s time to add
in inventory and/or waiting times.
For inventory, we simply count
the number of pieces in between
the processes and note them
under the triangle.
Information flow..
• We learned that production schedules each process step
in isolation. In other words, each work station gets its
unique production schedule.
• Scorpion’s customer sends 30 days electronic forecasts
as well as electronic daily orders. Conversely, Scorpion
sends its bread supplier an electronic weekly forecast.
Draw in the information flow.
If it is moves about electronically use a lighting bolt . If it is
communicated manually use a straight arrowed line.
During this step we also draw in our production control box.
Add in the timeline to the bottom of the value stream map. This saw
tooth looking line helps us separate the value added cycle time (taken
from data boxes) from the non value added time.
The last step in the process is to sum up all the “value-add” cycle
times and note them at the end of the timeline. Likewise, we also sum
up the “inventory” times and note that on the timeline.
Calculating Total Lead Time
• Queuing time - time that a “work unit” waits for a
downstream process to begin work on it.
• Cycle Time – the elapsed time for an individual activity
from start to completion.
• Total Cycle Time – Sum of all the cycle times for
individual activities in the process in the value stream.
Referred to as Value Added time (VAT) because it is the
time during which value is added as the work unit flows
through the process.
Total Lead Time = Total Cycle time + Total Queuing time
Questions to think about
•
•
•
•
• How many days of inventory do you have waiting
between processes?
• What is the total non-value added (or queuing)
time?
What is the total cycle time?
Can the Scorpion PB&J factory meet the customer
demand? How does the capacity relate to the takt time
we calculated?
What is the “pacemaker” process? (the process that
should set the pace for all the rest?)
What is wrong in this process flow? Use the 5 whys to
identify opportunities for improvement.