Unit 5: Quality Management

Question 1

What is the importance of quality control as identified by GE?

Answer 1

It drives leadership to be better by providing tools to think through tough issues. Turns an organization inside out, by focusing outwards, on the customer.

Question 2

What is Total Quality Management?

Answer 2

Managing the entire organization so it excels in all dimensions of products and services important to the customer.

Two goals: Careful design of the product of service. Ensuring that the organizations systems can consistently produce the design

Question 3

What is the Malcolm Baldrige National Quality Award; how and why it was instituted?

Answer 3

Establish in the US in 1987 to help companies structure their quality programs because of a quality shortfall in the US

Question 4

Design Quality

Answer 4

The inherent value of the product in the marketplace. Dimensions include: Performance, features, reliability / durability, serviceability, aesthetics, perceived quality

Question 5

What are the various costs of quality and how are they classified?

Answer 5

1) Appraisal
2) Prevention
3) Internal Failure
4) External Failure

Question 6

How can an effort to reduce the cost of quality sometimes result in an increase in productivity?

Answer 6

By introducing systems to manage processes, labor can sometimes be reduced leading to an increased productivity.

Question 7

What is the function of the QC department?

Answer 7

Performing cost of quality analyses - looking into expenditures related to achieving product or service quality

Question 8

What is meant by Six-Sigma quality? Work through Example 12.1 on page 304.

Answer 8

A statistical term to describe the quality goal of no more that 3.4 defects per million units. Also quality improvement philosophy and program

Question 9

What is Six-Sigma methodology? What is DMAIC methodology? See pages 304–305.

Answer 9

A systematic project oriented fashion through the define, measure, analyze, improve and control (DMAIC) - dumb managers always ignore customers

Question 10

What is meant by continuous improvement?

Answer 10

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Question 11

What are the analytical tools for Six-Sigma and continuous improvement? See Exhibit 12.5.

Answer 11

Flowcharts, run charts, pareto charts, check sheets, cause and effect diagrams, opportunity flow diagram, process control charts, failure mode and detect analysis, design of experiments,

Question 12

What are Six-Sigma roles and responsibilities?

Answer 12

1) Executive leaders - who are truly committed to Six Sigma and who champion it
2) Corporatewide training in Six Sigma concept and tools
3) Setting stretch objectives for improvement
4) Continuous reinforcement and rewards

Question 13

What does the Shingo system try to accomplish?

Answer 13

Drastic cuts in equipment setup times, use of source inspection and polka-yoke system to achieve zero defects

Question 14

What are “fail-safe procedures” and what is meant by poka-yoke?

Answer 14

Fail safe procedures are simple practices that help prevent errors. Poka-yokes are procedures that prevent mistakes from becoming defects

Question 15

What is ISO 9000 and ISO 14000 certification? Why is it important to become ISO 9000 certified?

Answer 15

International standards for quality management and assurance. It is important to become ISO 9000 certified because it is an international reference for quality management requirements in business to business dealings

Question 16

What is external benchmarking and what are the steps involved?

Answer 16

Looking outside the company to examine what excellent performers inside and outside the company’s industry are doing in the way of quality. 1) Identify processes needing improvement. 2) Analyze data

Question 17

What is statistical quality control (SQC)?

Answer 17

Techniques designed to evaluate quality from a conformance point of view

Question 18

What is the difference between assignable variation and common variation? Review formulas 13.1 (page 318) and 13.2 (page 319) and note what they mean.

Answer 18

Common variation is deviation in the output of a process that is random and inherent to the process itself. Whereas assignable variation can be clearly identified and managed.

Question 19

What is the purpose of sampling? What can a sample be assumed to tell us about the actual distribution of the process in question?

Answer 19

Samples allow for statistical calculations. A sample can be assumed to tell us about the actual variation in output

Question 20

What is meant by variability? Why is it impossible to have zero variability? What are upper and lower specification limits?

Answer 20

Upper and lower specification limits refers to the range of values in a measure associated with a process that is allowable given the intended use of the product of service

Question 21

Why does Genichi Taguchi believe that the traditional view of the cost of variability is not accurate? Review Exhibits 13.1 and 13.2.

Answer 21

1) From the customer’s view - there is no difference between a product just inside the specifications and just outside. The is a far greater difference in the quality of a product that is at the target, than at the limit. 2) As customers get more demanding there is a pressure to reduce variability, but the traditional sharp edged specification limits do not reflect this

Question 22

What is meant by the Six-Sigma limit?

Answer 22

When a part is designed, certain dimensions are specified to be within the upper and lower specification limits

Question 23

What is the relationship between the Six-Sigma limit and a design process?

Answer 23

Usually trade offs need to be made when designing a process for making a part.

Question 24

What is meant by the capability index? (Note: You are not required to understand the mathematics in calculating a capability index-scan this section.)

Answer 24

A capability index is used to measure how well our process is capable of producing relative to the design specifications

Question 25

What is meant by process control? What is meant by statistical process control?

Answer 25

Process control is concerned with monitoring quality while the product or service is being produced. Statistical process control involves testing a random sample of output from a process to determine whether it is producing items within a preselected range

Question 26

What are attributes? What is the difference between quality characteristics that are measurable and attributes?

Answer 26

Quality characteristics that are classified as either conforming or not conforming to a specification

Question 27

What is a P-Chart?

Answer 27

A p=chart graphs attribute samples with upper and lower control limits

Question 28

What are the four formulas used to establish upper and lower control limits for attributes? Review Formulas 13.4-to 13.7. You must know these formulas. Note Exhibit 13.5

Answer 28

Mean, standard deviation, variation and sample standard deviation

Question 29

What is the difference between sampling by variance and sampling by attributes?

Answer 29

Attributes are classified as either conforming, or non conforming. Whereas variance can be measured.

Question 30

Why is it advantageous to use a small sample size when measuring variables?

Answer 30

Larger samples are more costly and the process might change if more samples are taken

Question 31

How many samples should you take and how often? How should you set control limits?

Answer 31

Approximately four or five units. With about 25 samples to be analyzed.

Question 32

What are the formulas involved in constructing process distribution charts? Review Formulas 13.8 to 13.11.

Answer 32

x add image

Question 33

Work through the solution to the Example 13.4 problem. The charts in Exhibit 13.7 and 13.8 are used to look up upper and lower control limits for the X and the R charts. Learn how to use these tables. Exhibit 13.8 shows the two charts and the variability of the process. Review formulas 13.12 to 13.18.

Answer 33

x

Question 34

What is acceptance sampling? Work through the solution to Example 13.5.

Answer 34

Used on existing goods to determine the percentage of products that conform to specifications

Question 35

What is the purpose of a sampling plan? Be sure you know how the sampling plan is affected by the following: LTPD, AQL, , , c, and n.

Answer 35

A sampling plan is to test the lot to either find its quality or ensure that quality is what it is supposed to be.
n = number of units in the sample
c = acceptance number (max # of defective items in the sample before the lot is rejected)
AQL = acceptable quality level - lots are defined as high quality if they contain no more than a specified number level of defectives
LTPD = lot tolerance percent defective - lots are low quality if the % of defectives is greater than a specified amount
a = producers risk - the probability of rejecting a high quality lot
b = consumers risk - the probability of accepting a low quality lot

Question 36

What is meant by producer’s and consumer’s risk? Work through the solution to Example 13.6. Review the sampling plan table shown in Exhibit 13.10.

Answer 36

a = producers risk - the probability of rejecting a high quality lot 
b = consumers risk - the probability  of accepting a low quality lot

Question 37

What is an operating characteristics curve? What affects the shape of the curve? Study Exhibit 13.11

Answer 37

illustrate the probability

of accepting lots with varying percentages of defectives

Question 38

Conformance quality

Answer 38

The degree to which the product or service design specifications are met

Question 39

Quality at the source

Answer 39

The philosophy of making workers personally responsible for the quality of their output. Workers are expected to make the part correctly the first time and to stop the process immediately if there is a problem

Question 40

dimensions of quality

Answer 40

Criteria by which quality is measured