The document discusses quality control tools and techniques, including the Pareto chart and cause-and-effect diagram. It provides steps for constructing a Pareto chart to identify the most common problems or defects. Examples are given analyzing paint defect data from an automotive plant and refrigerator defect data. The document also explains how to create a cause-and-effect diagram to identify potential causes of a quality characteristic or problem, and includes an example analyzing causes of computer downtime.

1. Besterfield: Quality Control, 8th ed.. © 2009 Pearson Education, Upper Saddle River, NJ 07458.
All rights reserved
Quality Control
TQM-Tools and
Techniques
(Applications)
Asst. Prof. Dr. Mahmoud Abbas Mahmoud
2014 - 2015

2. Besterfield: Quality Control, 8th ed.. © 2009 Pearson Education, Upper Saddle River, NJ 07458.
All rights reserved
The Pareto Chart is a simple to use and
powerful graphic to identify where the
majority of problems in a process are
originating.
Pareto Chart

3. Besterfield: Quality Control, 8th ed.. © 2009 Pearson Education, Upper Saddle River, NJ 07458.
All rights reserved
Steps:
1. Determine the method of classifying the
data: by problem, cause, type of
nonconformity, etc
2. Decide if dollars (best), weighted frequency,
or frequency is to be used to rank the
characteristics
3. Collect data for an appropriate time interval
Constructing a Pareto Diagram

4. Besterfield: Quality Control, 8th ed.. © 2009 Pearson Education, Upper Saddle River, NJ 07458.
All rights reserved
Steps cont’d:
4. Summarize the data and rank order
categories from largest to smallest
5. Compute the cumulative percentage if it is
to be used
6. Construct the diagram and find the vital few
Constructing a Pareto Diagram

5. Besterfield: Quality Control, 8th ed.. © 2009 Pearson Education, Upper Saddle River, NJ 07458.
All rights reserved
The count of paint defects from an
automotive assembly plant are as in table
below ;
Use Pareto diagram to analyze these data!
Case 1
OtherOrange
peal
Thin
paint
Sealer
under
Off-
color
SagDirt in
paint
ScratchDefect
11254221652Count

6. Besterfield: Quality Control, 8th ed.. © 2009 Pearson Education, Upper Saddle River, NJ 07458.
All rights reserved
Pareto Diagram for Case 1

7. Besterfield: Quality Control, 8th ed.. © 2009 Pearson Education, Upper Saddle River, NJ 07458.
All rights reserved
Case 2
The count of defects found in refrigerators
tested by production line inspectors are as in
table below :
Use Pareto diagram to analyze these data!
OtherCompress
or (noise)
Paint
scratch
Water
line screw
loose
Shelf trim
loose
Handel trim
loose
Door not
aligned
Defect
78453211157158Count

8. Besterfield: Quality Control, 8th ed.. © 2009 Pearson Education, Upper Saddle River, NJ 07458.
All rights reserved
Cause-and-Effect Diagram
Cause-and-Effect Diagram
C
a
u
s
e
s
E
f
f
e
c
t
Quality
Characteristic
People Materials
Equipment Measurement
Work Methods
Environment
Primary
Cause
Secondary Cause

9. Besterfield: Quality Control, 8th ed.. © 2009 Pearson Education, Upper Saddle River, NJ 07458.
All rights reserved
Cause-and-Effect Diagram Case 1

10. Besterfield: Quality Control, 8th ed.. © 2009 Pearson Education, Upper Saddle River, NJ 07458.
All rights reserved
Cause-and-Effect Diagram Case 1

11. Besterfield: Quality Control, 8th ed.. © 2009 Pearson Education, Upper Saddle River, NJ 07458.
All rights reserved
Construct a cause and effect diagram
for the case of computer downtime !!!
Cause-and-Effect Diagram Case 2

12. Besterfield: Quality Control, 8th ed.. © 2009 Pearson Education, Upper Saddle River, NJ 07458.
All rights reserved
Cause-and-Effect Diagram