Value Stream Mapping

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Analysis of Material Transport
VALUE STREAM MAPPING
Outline
 Introduction to Value Stream Mapping
 Current State Map
 Data Collection
 Activity: Map Current State
Definition of Value Stream
A Value Stream includes all elements (both value added and non-value added)
that occur to a given product from its inception through delivery to the customer.
Requirements
Design
Assembly Plants
Raw Materials
Distribution
Parts Manufacturing
Customer
Value Stream Segment
Typically we examine the value stream from raw
materials to finished goods within a plant.
VALUE STREAM
PROCESS
Stamping
PROCESS
PROCESS
Welding
Assembly
Cell
Raw
Material
Finished
Product
It is also possible to map business processes
using Value Stream Mapping.
Value Stream Mapping
Value Stream Mapping (VSM) is a hands-on process to create a graphical
representation of the process, material and information flows within a value
stream.
Customer
Xpcs/ month
Std Pack Qty
# Shifts
PC & L
Steel Supplier
Level Box
DA1
DA2
DA3
Daily
Stamping
6 x / Day
Assembly
Welding
Finished Goods
Layout
3 Shifts
3 Shifts
3 Shifts
# Material Handlers
TAKT Time
TAKT Time
TAKT Time
Max Size
CT =
CT =
CT =
2 Shifts
C/O Time =
C/O Time =
C/O Time =
0 Overtime
DT =
DT =
DT =
Scrap =
Scrap / Rework=
Scrap / Rework =
WIP =
Small Lot
# Operators
WIP =
WIP =
Inv
.Time ? days
Proc
.Time
? days
? days
? days
? days
? days
? days
TPc
/t = ?
Future State Material, Information and Process Flows
with total Product Cycle Time
Objectives of Value Stream Mapping
 Provide
the means to see the material, process
and information flows.
 Support the prioritization of continuous
improvement activities at the value stream
 Provide the basis for facility layout
AND..
.
Eliminate Waste
Waste Opportunities











Producing defective parts
Passing on defective parts
Not communicating
improvements
Overproduction
Inventories
Motion
High nonvalue ratio
Transportation
Waiting
Counting
Inspection after the fact











Facility layout
Excessive setup times
Incapable process
Maintenance
Work method
Training (or lack of)
Supervisory ability (coaching)
Production planning/scheduling
Lack of workplace organization
Supplier quality/reliability
Lack of concern
Approaches
Percent of Lead Time
5
10
15
20
25
30
35
VA
45
50
55
60
NVA
NVA
VA
VA
40
NVA
65
70
75
80
85
90
95
100
Mapping Value Streams
Define all activities required to design, order, and provide a specific
product, from concept launch, to order to delivery, from raw
materials into the hands of the customer.
This includes:
• Information flow
• Material flow
• Inventory (WIP)
• Non value-added activities
• Transportation flow
Value Stream Mapping
What?
A visual tool for identifying all activities of the planning, and
manufacturing process to identify waste
Why?
Provides a tool to visualize what is otherwise usually
invisible
Who?
The leaders of each product family need to have a primary
role in developing the maps for their own area
When?
Where?
Develop a current state map before improvements are made
so that the efforts and benefits can be quantified
On the shop floor, not from your office—you need the real
information, not opinion or old data
Value Stream Map Symbols
3,000 units
Spot weld
C/T = 30 sec
ABC
plating
Process
Vendor
C/O = 10 min
3 shifts
2% scrap rate
= 1 day
Data box
Inventory
Finished
goods
Mon
and
Wed
Push
Supermarket
Physical pull
Shipment
Approach to Value Stream Mapping
Step #1

Identify customer requirements

Define method of delivery

Define typical quantity
requirements

It is OK that more than one
customer is served by this value
stream, but make sure that the
primary processes used are
similar
XYZ Corporation
Use a pencil rather than
computer
Recyclable tray

6 units/
week
18 units/day
9 lefts
9 rights
Approach to Value Stream Mapping
Step #2

Perform an upstream walk through each
process step, observing and documenting
as much of the following as possible:










Cycle time (operator & machine
cycle time)
Changeover times
Average inventory queue
Average production batch size
Number of operators at each
process
Package or container size
Available time (don’t count
breaks)
Scrap rate
Machine up time (availability)
Number of product variations
6 units/
week
XYZ Corporation
18 units/day
9 lefts
9 rights
Recyclable tray
Approach to Value Stream Mapping
Step #3
Record as much data as is pertinent in the process description box
Process Description
Crew size:
Output:
per:
C/T
C/O
Up time:
Waste %
Time available
I
The triangle symbol identifies inventory; this
can be expressed in pieces or in time (how
many hours, days, or weeks of inventory).
The arrow connects to the next
process. A straight arrow can stand for
a push, a curved arrow can symbolize a
physical pull from a kanban location.
Approach to Value Stream Mapping
Step #4
•
•
•
•
•
Dream about perfection
Think outside the box
Develop alternatives to the current state map—Muda free
Focus on velocity
Test each idea if it supports:
 One-piece flow
 Pull
Approach to Value Stream Mapping
Step #4
•
•
•
•
•
•
•
•
•
Dream about perfection
Think outside the box
Develop alternatives to the current state map—Muda free
Focus on velocity
Test each idea against TOP— in other words, does it support:
 One-piece flow
 Pull
Develop a “future state” map that visually describes the goal
Break down the future state map into manageable steps
Develop a Gantt chart (time-phased project plan)
Identify the kaizen events that will need to take place
Fast Track Process Improvement
What process?
Customer +
requirements
Improvements to
a) fix root causes
b) meet C requirements
Metrics (1-3 months)
Map current
process
Identify
hot-spots
Root-cause
analysis
Communicate plan
Implement,
measure,
fine-tune
Current State Map (Simplified)
Weekly shipments:
700,000 lineal
50,000 pieces
6-day lead time as shown
5,350 finished pieces/day
5%
90 %
Staging
5%
10%
90%
Lam #1
I
268
pieces
Resaw (4 saws)
Molder #4
Prime
4,500
C/T= 7.2 sec
pieces
C/O= 5 - 25 min
% Crew:days= 100%
swing = 0%
I
Crew size: 1 1/3
Run speed 184 ft/min.
Output:1,584 pieces/hr
9000
C/T= 2.3 sec
pcs
C/O= 7 - 30 min
% Crew Days =100%
Swing =0%
% Reliability = 98%
% Reliability = 95%
% Reliability = 98%
% Reliability =73%
Waste = 1/2%
Waste =
Waste = 1/2%
Waste = 3%
Sec available 27,000
Sec available 108,000
Sec available27,000
Sec available 27,000
Weekly hr = 5
Weekly hr = 31.6
Weekly hr = 38.9
Weekly hr = 18.5
Crew size: 4
Run speed 58 ft/min
Output: 500 pieces/hr
.5 hr
I
48 hr
1,034 sec
Crew size: 4
Run speed 300 ft/min
Output:1,285 pieces/hr
Crew size: 3
Run speed: 3,15 l ft/min
Output:1,350 pieces/hr
9,000
C/T= 2.8 sec
pieces C/T= 1.3 sec
C/O= 5 - 45 min
C/O= 1 min - 1 hr
% Crew:days= 100%
% Crew:days =100%
swing = 0 %
swing =
48 hr
230 sec
I
48 hr
280 sec
130 sec
Value-added Ratios VA:NVA
Process Time
Shear
Punch
Deburr
Form
Hrdwr
Pack
Total
10 blanks
10 blanks
100 parts
100 parts
100 parts
100 parts
Lead time
=
=
=
=
=
=
=
15 min
30 min
10 min
40 min
15 min
10 min
120 min
1.0
1.0
0.5
1.0
1.5
0.5
5.5
day
day
day
day
day
day
day (7,920 min)
120 is 1.5% of total lead time or a ratio of 1:66
Future State Map
Weekly shipments:
700,000 lineal
50,000 pieces
1-day lead time as shown



5,350 finished pieces/day
Free up $50,625 inventory
96% improvement in lead time
Instant quality feedback
95%
Staging
5%
Lam #1
I
Crew size: 4
Run speed 58 ft/min
Output: 500 pieces/hr
268 pieces
C/T= 7.2 sec
C/O= 5 -25 min
% Crew:days= 100%
swing = 0%
I
4,500
pieces
Primed lineal cell
Crew size: 6
Run speed 300 ft/min
Output: 1,285 pieces/hr
C/T= 2.8 sec
C/O= 10 - 20 mins
% Crew days =100%
% Reliability = 98%
% Reliability = 95 %
Waste = 1/2%
Waste = 1.2%
Sec available 27,000
Sec available 27,000
Weekly hr = 5
.5 hr
Weekly hr = 38.9
3 hr
1,034 sec
VA Ratio =1:12
.2 hr
199 sec
Production lead
time = 3.7 hr
Value-added time
1,233 sec
Improvement Data
Before
After
Improvement

5 forklift movements

3 forklift movements

40% reduction

28,118 pieces in WIP

10,118 pieces in WIP

64% reduction

144 hr lead time

3.7 hr lead time

97% reduction

273 labor hr/week

235 labor hr/week

14% reduction

9,000 ft2 required

2,760 ft2 required

70% reduction
Value Stream Mapping: Summary
 Develop a current state map first
 Clearly document the future state map so
everyone can visualize it
 Perform the improvements in manageable steps
 Be good at finishing—use policy deployment
 Don’t wait for the entire process to complete,
celebrate the journey
References
Dr. Kenneth Andrews
Garry Conner
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