Chapter 3, Part 2

Quality Management Tools

Operations Management - 5 th Edition

Roberta Russell & Bernard W. Taylor, III

Copyright 2006 John Wiley & Sons, Inc.

Beni Asllani University of Tennessee at Chattanooga

PDCA Cycle – A Process for Quality Improvement

4. Act Institutionalize improvement; continue cycle.

1. Plan Identify problem and develop plan for improvement.

3. Study/Check Assess plan; is it working?

2. Do Implement plan on a test basis.

Seven Quality Tools

    Pareto Analysis Flow Chart Check Sheet Histogram    Scatter Diagram SPC Chart Cause-and-Effect Diagram Copyright 2006 John Wiley & Sons, Inc.

3-3

Pareto Analysis – Based on Data Used to Set Priorities

CAUSE NUMBER OF DEFECTS Poor design Wrong part dimensions Defective parts Incorrect machine calibration Operator errors Defective material Surface abrasions 80 16 12 7 4 3 3 125 PERCENTAGE 64 % 13 10 6 3 2 2 100 %

20 10 0 70 (64) 60 50 40 30

Pareto Chart

(13) (10) (6) (3) (2) (2) Causes of poor quality

Flow Chart – Diagram of Process Used to Examine Overall Process Flow

Start Operation Operation Decision Operation Operation Operation Decision Finish

Flow Chart Symbols

 Circle – used for Start and Finish.

  Rectangle – used for an operation – a step that adds value. At least 1 arrow in. Only one arrow out.

Diamond – used for a decision – must have at least 2 possible outcomes. For each outcome, there must be one arrow from the decision box. Each arrow is labeled with its outcome.

Check Sheet – A Tool for Collecting Data Easily

COMPONENTS REPLACED BY LAB TIME PERIOD: 22 Feb to 27 Feb 2002 REPAIR TECHNICIAN: Bob TV SET MODEL 1013 Integrated Circuits Capacitors Resistors Transformers Commands CRT | |||| |||| |||| |||| |||| |||| || || ||||

Histogram – Shows Distribution of Data Data Can Be Categorical or Numerical Number of occurences in each bar should be specified.

Y

Scatter Diagram – Shows correlation between 2 variables

X

Control Chart

24 21 18 15 12 9 6 3 UCL = 23.35

c = 12.67

2 LCL = 1.99

4 6 8 10 Sample number 12 14 16

Cause-and-Effect Diagram – shows possible causes for a quality problem.

Measurement Faulty testing equipment Incorrect specifications Improper methods Human Poor supervision Machines Out of adjustment Lack of concentration Inadequate training Tooling problems Old / worn Quality Problem Inaccurate temperature control Dust and Dirt Defective from vendor Not to specifications Material handling problems Environment Materials Poor process design Ineffective quality management Deficiencies in product design Process