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Transcript QualityTools
Seven Tools for TQM
6-1
Tools for TQM
Quality Function Deployment
House of Quality
Taguchi technique
Quality loss function
Pareto charts
Process charts
Cause-and-effect diagrams
Statistical process control
6-2
Tools of TQM
Tools for generating ideas
Check sheet
Scatter diagram
Cause and effect diagram
Tools to organize data
Pareto charts
Process charts (Flow diagrams)
Tools for identifying problems
Histograms
Statistical process control chart
6-3
Pareto Analysis of Wine Glass
Defects (Total Defects = 75)
60
88%
54
50
97%
93%
100% 100%
72%
80%
40
60%
30
40%
20
12
5
10
4
2
0
20%
0%
Scratches
72%
Porosity
Nicks
Contamination
16%
5%
4%
Causes, by percent total defects
6-4
Misc.
3%
Cumulative Percent
Frequency (Number)
70
Process Chart
Shows sequence of events in process
Depicts activity relationships
Has many uses
Identify data collection points
Find problem sources
Identify places for improvement
Identify where travel distances can be reduced
6-5
Cause and Effect Diagram
Used to find problem sources/solutions
Other names
Fish-bone diagram, Ishikawa diagram
Steps
Identify problem to correct
Draw main causes for problem as ‘bones’
Ask ‘What could have caused problems in these areas?’
Repeat for each sub-area.
6-6
Cause and Effect Diagram
Example
Problem
Too many
defects
6-7
Cause and Effect Diagram
Example
Method
Manpower
Main Cause
Too many
defects
Material
Machinery
Main Cause
6-8
Cause and Effect Diagram
Example
Method
Manpower
Drill
Overtime
Too many
defects
Wood
Steel
Material
Lathe
Machinery
Sub-Cause
6-9
Cause and Effect Diagram
Example
Method
Manpower
Tired
Overtime
Drill
Slow
Old
Wood
Steel
Material
Lathe
Machinery
6-10
Too many
defects
Fishbone Chart - Problems with
Airline Customer Service
6-11
Statistical Process Control (SPC)
Uses statistics & control charts to tell when to adjust
process
Developed by Shewhart in 1920’s
Involves
Creating standards (upper & lower limits)
Measuring sample output (e.g. mean wgt.)
Taking corrective action (if necessary)
Done while product is being produced
6-12
Statistical Process Control Steps
Start
Produce Good
Provide Service
Take Sample
No
Assign.
Causes?
Yes
Inspect Sample
Stop Process
Create
Control Chart
Find Out Why
6-13
Process Control Chart
Plot of Sample Data Over Time
Sample Value
80
Sample
Value
UCL
60
40
Average
20
LCL
0
1
5
9
13
17
Time
6-14
21
Control Chart
6-15
Patterns to Look for in
Control Charts
6-16
Basic Steps in Problem Solving
1. Define the problem and establish an improvement
goal
2. Collect data
3. Analyze the problem
4. Generate potential solutions
5. Choose a solution
6. Implement the solution
7. Monitor the solution to see if it accomplishes the goal
The PDSA Cycle
Plan
Act
Do
Study
Process Improvement
Process Improvement: A systematic approach to
improving a process
Process mapping
Analyze the process
Redesign the process
The Process Improvement Cycle
Select a
process
Document
Study/document
Evaluate
Implement the
Improved process
Seek ways to
Improve it
Design an
Improved process
Process Improvement and Tools
Process improvement - a systematic approach to
improving a process
Process mapping
Analyze the process
Redesign the process
Tools
There are a number of tools that can be used for
problem solving and process improvement
Tools aid in data collection and interpretation, and
provide the basis for decision making
Methods for Generating Ideas
Brainstorming
Quality circles
Interviewing
Benchmarking
5W2H
Quality Circles
Team approach
List reduction
Balance sheet
Paired comparisons