Six Sigma Quality Engineering

1
Six Sigma Quality Engineering

• Week 4
• Chapters 5 (Measure Phase)

2
Chapter 5 Outline

• Process Map
• Cause Effect Matrix
• Fishbone Diagram
• Fayetteville Paint Line
• Lean Kaizen
• Reproducibility Repeatability (Gage RR)
• Capability Analysis
• Components of Variation Studies
• FMEA

3
What is a Process Map?

• A process map is a graphical representation of
  the flow of a process
• A detailed process map includes information that
  can be used to improve the process, such as
• Process Times
• Quality
• Costs
• Inputs
• Outputs

4
Types of Process Map

• Basic process map
• Detailed process map
• Work-flow (spaghetti diagrams)
• Top-down flowchart
• Deployment flowchart
• Opportunity flowchart
• Current State / Future state maps

5
Uses of a Process Map

• Identify areas for focus of improvement efforts
• Identify and eliminate non-value added steps
• Combine operations
• Assist root cause analysis
• Baseline for failure mode and effect analysis
  (FMEA)
• Identify potential controllable parameters for
  designed experiments
• Determine needed data collection points
• Eliminate unnecessary data collection steps

6
Detailed Process Map Example
7
Process Maps

• Should include
• Major activities and tasks
• Sub-processes
• Process boundaries
• Inputs
• Outputs
• Documents reality, not how you think the process
  is supposed to be completed
• Should identify opportunities for improvement

8
Steps for Process Mapping

• Scope the process
• Identify the start and end points of the process
  of interest
• Document the top level process steps
• Create a flow chart
• Identify the inputs and outputs
• What are the results of doing each process step?
  (Ys)
• What impacts the quality of each Y? (xs)
• Characterise the inputs

9
Characterising Inputs

• Inputs can be classified as one of three types
• Controllable (C)
• Things you can adjust or control during the
  process
• Speeds, feeds, temperatures, pressures.
• Standard Operating Procedures (S)
• Things you always do (in procedures or common
  sense things)
• Cleaning, safety.
• Noise (N)
• Things you cannot control or don not want to
  control(too expensive or difficult)
• Ambient temperature, humidity, operator...

10
Example
Outputs (Ys) Diameter Taper Surface finish
Inputs (xs) Rotation speed Traverse speed Tool
type Tool sharpness Shaft material Shaft
length Material removal per cut Part
cleanliness Coolant flow Operator Material
variation Ambient temperature Coolant age
C C C C C C C S C N N N S
11
Suggested Elements
Too little detail will not expose the problem.
Too much detail will hide the problem.
12
Order Entry Process MapAs-Is
BEFORE 40 NVA STEPS
NOTE FROM THE CUSTOMERS VIEWPOINT ALL OF ORDER
ENTRY IS NON-VALUE ADDED
13
Order Entry Process MapNew
REMEMBER FROM THE CUSTOMERS VIEWPOINT ALL OF
ORDER ENTRY IS NON-VALUE ADDED
We eliminated the steps that were NVA and
UNNECESSARY (WASTE)
BEFORE 40 NVA STEPS
AFTER 11 NVA STEPS
14
Types of Process Map

• Basic process map
• Detailed process map
• Work-flow (spaghetti diagrams)
• Top-down flowchart
• Deployment flowchart
• Opportunity flowchart
• Current State / Future state maps

15
Work-flow or Spaghetti Diagram

• A work flow diagram is a picture of the movements
  of people, materials, documents, or information
  in a process.
• Start by tracing these movements onto a floor
  plan or map of the work space.
• The purpose of the work-flow diagram is to
  illustrate the inefficiency in a clear picture.
• How can you make the map look simpler? What lines
  can you eliminate?

16
56 Frame (Small Motor) Assy Fabrication - Before
x
x
x
x
BEFORE KAIZEN Area 4640 sq ft Operator Travel
3696 ft Product Travel 1115 ft
x
x
x
x
x
17
Cause Effect

• Objectives
• To understand the benefits of Cause Effect
  Analysis
• To understand how to construct a C E Diagram
• Analysis
• A method a work group can use to identify the
  possible causes of a problem
• A tool to identify the factors that contribute to
  a quality characteristic

18
Uses of C E Analysis

• Visual means for tracing a problem to its causes
• Identifies all the possible causes of a problem
  and how they relate before deciding which ones to
  investigate
• C E analysis is used as a starting point for
  investigating a problem

19
Fishbone Diagram

• Effect
• The problem or quality characteristic
• The effect is the outcome of the factors that
  affect it

Effect
20
Causes

• All the factors that could affect the problem or
  the quality characteristic
• Five Major Categories
• Materials
• Methods
• People
• Machines
• Environment

21
Machine
Environment
Effect
People
Methods
Material
22
The Eight Steps in Cause and Effect Analysis

• Define the Effect
• Identify the Major Categories
• Generate Ideas
• Evaluate Ideas
• Vote for the Most Likely Causes
• Rank the Causes
• Verify the Results
• Recommend Solutions

23
Fayetteville Paint Line Cause and Effect

• Benefit
• Gain new knowledge and perspectives by sharing
  ideas with others
• Helps us understand our processes
• Provides a basis for action
• Whenever a problem is discovered, using CE
  analysis forces us to take a proactive stance by
  seeking out causes

24
Fayetteville Paint Line

• Instructions

This table provides the initial input to the FMEA
and experimentation. When each of the output
variables (requirements) are not correct, that
represents potential "EFFECTS". When each input
variable is not correct, that represents "Failure
Modes". 1. List the process output variables
2. Rate each output on a 1-to-10 scale to
importance to the customer 3. List process input
variables (from the process map) 4. Rate each
input's relationship to each output variable
using a 0, 1, 3, 9 scale 5. Select the high
ranking input variables to start the FMEA
process Determine how each selected input
variable can "go wrong" and place that in the
Failure Mode column of the FMEA.

25
2
1
56
3
4
26
What is a Kaizen Blitz?
A Kaizen Blitz is a cross functional multi-level
team of 5 to 10 members working intensely for 10
to 14 hours a day, to rapidly develop, test and
refine solutions to problems and leave a new
solution in place in just a few days. They dont
plan, they dont propose, they do.
This focus on immediate change is what sets
Kaizen activity apart from other improvement
tools.
27
How do you get started?
A Kaizen Blitz, used in conjunction with the
Toyota Production System (TPS) and current Lean
Manufacturing principles, can serve as a catalyst
for the initial implementation of a plant wide
Lean Manufacturing initiative.
HOW ?
Depending on the individual event, many of the
Lean elements previously mentioned are tackled
during a Kaizen Blitz event.
28
Cycle of an Event
Schedule the Event
Recognize the Needfor Change
Select System / Process to Optimize
3
2
4
Our Way of Life
1
5
Develop the Objectives
Formalize the Change
12
Process Owner Review Explains Objectives
6
11
Process Owner Accepts Change
7

• Learning the Tools
• 5S, Process Flow
• TAKT / Cycle Time

10
8
9
Make the Change

• Capture the Details
• Data Gathering
• Detail Analysis

Set Goals, Make a Plan
29

• The How To Guide
• To Lean Implementation

30
Step One

• Choose Your Project Well
• High Probability For Success
• Good Visibility
• Short In Duration
• Requires Several Lean Tools
• Is Measurable

31
Step Two

• Choose Your Team Well
• Open Minded And Enthusiastic
• Select People Who Work With The Product
• Operators
• Maintenance People
• Supervisors
• ME/IE
• Planners

32
Step Three

• Train! Train! Train!
• Overview Of Six Sigma
• Continuous Improvement
• Single Piece Build (Use The Stockless
  Production Video Made By Hewlett Packard
• Use Your Black Belts

33
Step Four

• Calculate Takt Time
• This Is The Customers Drum Beat
• Takt Time Units Purchased Per Day Divided Into
  Actual Time Available In A Shift
• Example 27,000 Seconds / 20 Units 1350
  Seconds Per Unit Or (1) Unit Every 22.5 Minutes

34
Takt Time
The time (pace) required to produce a product
based on customer demand.
Time Available Customer Demand
Often expressed as
TAKT TIME
Example Elevator Manufacturer
-Customer Demand 50 Hydraulic Elevators /
Week -Daily Demand 10 Hydraulic Elevators -Time
Available 435 Minutes / Day (480 min less
cleanup, breaks)
435 / 10 43.5 Minutes per elevator TAKT TIME
This pace must be maintained in order to satisfy
customer demand!
35
Cycle Time
The time for an operator to do a prescribed
task and return to his/her original stance.
36
Lead Time
The amount of time it takes to convert raw
materials into finished goods (External
Customer) or to move goods from one part of the
process to another (Internal Customer)
37
Cycle Time vs. Lead Time
Lead Time
Task 1
Task 2
Task 3
Task 4
Task 5
MOVE
WAIT
SET-UP
RUN
Cycle Time
38
Takt Time vs. Lead Time
gtTAKT Time is a rate of demand gtLead Time is how
long the whole process takes gtThey are NOT
related!
Lead Time
1 Unit / Minute TAKT Time
PROCESS
WIP
Can a process have a 1 hour TAKT Time and a 6
month Lead Time?
39
Step Five

• Study The Project
• Team Meetings To Discuss The Project
• Set Objectives
• 25 Improvement In Through Put
• 50 Reduction In Floor Space
• 65 Reduction In Inventory
• Meeting The Takt Time
• Establish The Metrics

40
Batch vs. One-Piece Flow
(Process oriented layout with Lot Size
5) Processing Time 1 Minute / Unit
Process Flow
A
B
C
D
0
5
10
15
20
TIME ELAPSED (MINUTES)
Manufacturing Lead Time
NOTE Typically, the distances between process
is long in a process oriented layout, making
difficult to transfer units one-by-one.
41
Batch vs. One-Piece Flow
(Process oriented layout with Lot Size
1) Processing Time 1 Minute / Unit
Process Flow
A
B
C
D
0
1
2
3
4
TIME ELAPSED (MINUTES)
Add the Balance of Units (4 x 1/Unit)
8
Manufacturing Lead Time
42
Questions? Comments?