Seven Steps to Creating a Value Stream Mapping JAN2014
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Transcript of Seven Steps to Creating a Value Stream Mapping JAN2014
Seven Steps to Creating a Value Stream Map (VSM)
Process Steps & Case Study
Revision: New
Date: Jan. 2014
Content:
• Purpose
• Process Steps
• Case Study
Purpose:
– This presentation identifies the steps needed to create a Value Stream Map VSM.
– An example is provided using a case study that allows the user to witness the development of a VSM.
Process Step Approach
2. Draw Process Steps
3. Enter Process Data
4. Enter Inventory Count
5. Draw Material Flow : Supplier to Manufacturer, Manufacturer to Customer
6. Draw Information Flow and internal material flow
7. Calculate Lead Time, processing time & max value add %
1. Identify Customer Requirements
• Step 1 : Identify Customer Requirements» Customer Demand
» Number of Shifts
» Pack Size
• Step 2 : Draw Process Steps» For ease, combine parallel process steps
• Step 3 : Enter Process Data» Cycle Time
» Changeover Time
» Uptime
» Amount of Operators
Seven Steps to Creating a VSM
Seven Steps to Creating a VSM
• Step 4 : Enter Inventory Count» Enter inventory count between each process step
» Don't forget inventory at the beginning before 1st process step
• Step 5 : Draw Material Flow» From supplier
» To customer
• Step 6 : Draw information & internal material flow» From Aircraft Assembly Plant to supplier
» From production planning to process steps
Seven Steps to Creating a VSM
• Step 7 : Calculate lead time, processing time & maximum value add %
– Processing Time» Sum of all cycle times
– Lead Time» Processing time + sum of all inventory times
» Inventory time = inventory quantity/daily customer demand
For example, if the customer requires 20 items per day and there are 40 items in inventory. There is 2 days inventory time (waiting time)
» Convert inventory time from days to minutes (include breaks, but not uptime or changeover time)
– Maximum Value Add %
» Max. Value add % = (processing time/lead time) x 100
Seven Steps to Creating a VSM
• Introduction
– The Joe Bloggs Stamping Company produces several components for Aircraft Part
Assembly Plants
– This case concerns one product family ; a Titanium Bracket Sub-Assembly in two
types A1 and A2
– These components are sent to Assembly Plant
• Customer Requirements
– 320 pieces per month
– 200 per month Type A1
– 120 per month Type A2
– Customer Plant operates 2 shifts
– Palletised returnable tray packaging with 1 bracket per tray and up to 10 trays per
pallet. The Customer orders in multiples of trays
– Ships once daily to the Assembly Plant by road
Case Study: Joe Bloggs Stamping Company
Seven Steps to Creating a VSM
• Work Time– 20 days in a month
– 2 shift operation in all production departments
– 8 hours every shift, with overtime if necessary
– Two 10 minute planned breaks during each shift
– Manual processes stop during breaks
– Unpaid lunch, all processes continue
• Production Processes– “Joe Bloggs “ process for this product family involves stamping a metal part followed by
welding and subsequent assembly. The components are then stored and driven to the AssyPlant on a daily basis.
– Switching between Type A1 and A2 brackets requires a 1 hour changeover in stamping and a 10 minute fixture change in the welding processes.
– Coils (500m) are supplied by Coils R Us
– Deliveries are made to “Joe Bloggs” on Tuesdays and Thursdays by truck.
Case Study: Joe Bloggs Stamping Company
Seven Steps to Creating a VSM
Case Study: Joe Bloggs Stamping Company
• “Joe Bloggs” Production Control Department– Receives Assy Plants 90/60/30 day forecasts and enter them into MRP via
Electronic Data Interchange (EDI)
– Issues “Joe Bloggs” 6 week forecast to Coils R Us via EDI
– Secures coil steel by weekly faxed order release to Coils R Us
– Receives daily firm order from Assy Plant via EDI
– Generates MRP (manufacturing resource planning) based weekly departmental requirements based on customer order, Work in Process (WIP) inventory levels, Finished Goods (F/G) inventory levels, anticipated scrap and downtime.
– Issues requirements to Coils R Us for 500m coils
– Issues weekly build schedules to Stamping, Welding and Assembly processes
– Issues daily shipping schedule to Shipping Department
Seven Steps to Creating a VSM
Case Study: Joe Bloggs Stamping Company
All production processes occur in the following order, each piece goes through all process
1. Stamping(The press makes parts for many products)
– 1 Operator to run press
– Automated 10 ton press with coil (automated material feed)
– Cycle Time : 1 minute (60 pieces an hour)
– Changeover Time : 1 Hour (good piece to good piece)
– Machine Reliability : 85%
– Observed Inventory
• 4000m of coils before stamping (enough to make 80 brackets)
• 150 pieces of Type A1 finished stampings
• 24 pieces of Type A2 finished stampings
Seven Steps to Creating a VSM
Case Study: Joe Bloggs Stamping Company
2. Spotweld Workstation 1(dedicated to this product family)
– Manual process with 1 operator– Cycle Time : 39 minutes
– Changeover Time : 10 minutes (fixture change)
– Reliability : 100%
– Observed Inventory
• 36 pieces of Type A1 & 6 pieces of Type A2 after process
3. Spotweld Workstation 2(dedicated to this product family)
– Manual process with 1 operator
– Cycle Time : 46 minutes
– Changeover Time : 10 minutes (fixture change)
– Reliability : 80%
– Observed Inventory
• 6 pieces of Type A1 before Spotweld 2
• 16 pieces of Type A1 & 18 pieces of Type A2 after Spotweld
Seven Steps to Creating a VSM
Case Study: Joe Bloggs Stamping Company
4. Assembly Workstation 1(dedicated to this product family)– Manual process with 1 operator– Cycle Time : 62 minutes– Changeover Time : none– Reliability : 100%– Observed Inventory after process step
• 42 pieces of Type A1 & 6 pieces of Type A2
5. Assembly Workstation 2(dedicated to this product family)– Manual process with 1 operator– Cycle Time : 40 minutes– Changeover Time : none– Reliability : 100%– Observed finished goods inventory in warehouse
• 27 pieces of Type A1 & 14 pieces of Type A2
6. Shipping DepartmentRemove parts from finished goods warehouse and prepares them for shipment to the customer
Seven Steps to Creating a VSM
Mon.
+ Wed.
FIFO
Assembly
XYZ
Corporation
C/T = 45 sec
C/O = 30 min
3 Shifts
2% Scrap
Manufacturing
Process
Outside
Sources
Data BoxI
300 pieces
1 day
Inventory
Truck
Shipment
PUSH
Arrow
Finished Goods
to Customer
First-In-First-Out
Sequence Flow
Supermarket
Withdrawal
Material Flow Icons
Seven Steps to Creating a VSM
Weekly
ScheduleOXOX
Manual
Information Flow
Electronic
Information Flow
Schedule Load Levelling
Withdrawl
Kanban
Production
Kanban
Signal Kanban
Kanban Post
Sequenced-Pull Ball
“Go See”
Scheduling
Kanban Arriving
in Batches
Information Flow Icons
Seven Steps to Creating a VSM
Improvement Lightening
Burst
Buffer or Safety Stock
Operator
General Icons
Seven Steps to Creating a VSM
C/T = 1 Min
C/O = 1 Hour
Uptime = 85%
1 x
10T
Stamping
C/T = 39 Min
C/O = 10 Min
Uptime = 100%
1 x
Spot Weld 1
C/T = 46 Min
C/O = 10 Min
Uptime = 80%
1 x
Spot Weld 2
C/T = 62 Min
C/O = 0
Uptime = 100%
1 x
Assembly 1
C/T = 40 Mins
C/O = 0
Uptime = 100%
1 x
Assembly 2 Shipping
320 Pieces/Month
200 A1
120 A2
2 Shifts
Pack Size 1
Aircraft Assembly
Plant
I
27A1
14A2
I
42A1
6A2
I
16A1
18A2
I
42A1
6A2
I
150 A1
24A2
I
80
Identify Customer Requirements, Draw Process Steps, Enter Process Data and Enter Inventory Count
Case Study: Steps 1-4
Seven Steps to Creating a VSM
C/T = 1 Min
C/O = 1 Hour
Uptime = 85%
1 x
10T
Stamping
C/T = 39 Min
C/O = 10 Min
Uptime = 100%
1 x
Spot Weld 1
C/T = 46 Min
C/O = 10 Min
Uptime = 80%
1 x
Spot Weld 2
C/T = 62 Min
C/O = 0
Uptime = 100%
1 x
Assembly 1
C/T = 40 Mins
C/O = 0
Uptime = 100%
1 x
Assembly 2 Shipping
320 Pieces/Month
200 A1
120 A2
2 Shifts
Pack Size 1
Aircraft Assembly
Plant
I
27A1
14A2
I
42A1
6A2
I
16A1
18A2
I
42A1
6A2
I
150 A1
24A2
I
80
1 x Daily
Tues &
Thurs
Coils R Us
500M Coils
Draw Material Flow : Supplier to Manufacturer and Manufacturer to Customer
Case Study: Step 5
Seven Steps to Creating a VSM
C/T = 1 Min
C/O = 1 Hour
Uptime = 85%
1 x
10T
Stamping
C/T = 39 Min
C/O = 10 Min
Uptime = 100%
1 x
Spot Weld 1
C/T = 46 Min
C/O = 10 Min
Uptime = 80%
1 x
Spot Weld 2
C/T = 62 Min
C/O = 0
Uptime = 100%
1 x
Assembly 1
C/T = 40 Mins
C/O = 0
Uptime = 100%
1 x
Assembly 2 Shipping
320 Pieces/Month
200 A1
120 A2
2 Shifts
Pack Size 1
Aircraft Assembly
Plant
I
27A1
14A2
I
42A1
6A2
I
16A1
18A2
I
42A1
6A2
I
150 A1
24A2
I
80
1 x Daily
Tues &
Thurs
Coils R Us
500M Coils
MRP
Production Planning
Daily Expedite
6 Week Forecast
Weekly Fax
30/60/90 Day F/C
Weekly Plan
Daily
Shipping
Plan
Draw Information Flow and Internal Material Flow
Case Study: Step 6
Seven Steps to Creating a VSM
C/T = 1 Min
C/O = 1 Hour
Uptime = 85%
1 x
10T
Stamping
C/T = 39 Min
C/O = 10 Min
Uptime = 100%
1 x
Spot Weld 1
C/T = 46 Min
C/O = 10 Min
Uptime = 80%
1 x
Spot Weld 2
C/T = 62 Min
C/O = 0
Uptime = 100%
1 x
Assembly 1
C/T = 40 Mins
C/O = 0
Uptime = 100%
1 x
Assembly 2 Shipping
320 Pieces/Month
200 A1
120 A2
2 Shifts
Pack Size 1
Aircraft Assembly
Plant
I
27A1
14A2
I
42A1
6A2
I
16A1
18A2
I
42A1
6A2
I
150 A1
24A2
I
80
1 x Daily
Tues &
Thurs
Coils R Us
500M Coils
MRP
Production Planning
Daily Expedite
6 Week Forecast
Weekly Fax
30/60/90 Day F/C
Weekly Plan
Daily
Shipping
Plan
4600
Mins
1 Min
2392
Mins
2760
Mins
1932
Mins
2760
Mins
10,028
Mins
40 Mins62 Mins46 Mins39 Mins Processing Time =
188 Mins
Production Lead
Time = 26.8 Days
Case Study: Step 7
Calculate Lead Time and Processing Time
Seven Steps to Creating a VSM
1 Working Day8 Hours x 2 Shifts
8 x 60 x 2 = 960 Minutes
960 Minutes – Breaks
960 – 40 = 920 Minutes
Convert Lead Time to MinutesLead Time = 26.8 Days
26.8 x 920 = 24,660 Minutes
Calculate Max. VA %Max VA% = (processing time / lead time) x 100
= (188 / 24660) x 100
= 0.76%
• Therefore the Max VA% indicates that the item has only been worked on for 0.76% of the time it has
been within the value stream (touch time)
• The 0.76% is not all value add time because some of the cycle time within the process steps could be
waste
• This is why it is called Maximum Value Add %, because even with a perfect process (with no waste)
the Max VA % could only ever be 0.76%
Case Study: Step 7 –Max Value Add %