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


• 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


• 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


• 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


• 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.




• “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



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



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%


• 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%


• 6 pieces of Type A1 before Spotweld 2

• 16 pieces of Type A1 & 18 pieces of Type A2 after Spotweld



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


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


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


Improvement Lightening

Burst

Buffer or Safety Stock

Operator

General Icons


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


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


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


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


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 %

Seven Steps to Creating a Value Stream Mapping JAN2014

Documents