Unit 5: Quality Management Flashcards
What is the importance of quality control as identified by GE?
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.
What is Total Quality Management?
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
What is the Malcolm Baldrige National Quality Award; how and why it was instituted?
Establish in the US in 1987 to help companies structure their quality programs because of a quality shortfall in the US
Design Quality
The inherent value of the product in the marketplace. Dimensions include: Performance, features, reliability / durability, serviceability, aesthetics, perceived quality
What are the various costs of quality and how are they classified?
1) Appraisal
2) Prevention
3) Internal Failure
4) External Failure
How can an effort to reduce the cost of quality sometimes result in an increase in productivity?
By introducing systems to manage processes, labor can sometimes be reduced leading to an increased productivity.
What is the function of the QC department?
Performing cost of quality analyses - looking into expenditures related to achieving product or service quality
What is meant by Six-Sigma quality? Work through Example 12.1 on page 304.
A statistical term to describe the quality goal of no more that 3.4 defects per million units. Also quality improvement philosophy and program
What is Six-Sigma methodology? What is DMAIC methodology? See pages 304–305.
A systematic project oriented fashion through the define, measure, analyze, improve and control (DMAIC) - dumb managers always ignore customers
What is meant by continuous improvement?
x
What are the analytical tools for Six-Sigma and continuous improvement? See Exhibit 12.5.
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,
What are Six-Sigma roles and responsibilities?
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
What does the Shingo system try to accomplish?
Drastic cuts in equipment setup times, use of source inspection and polka-yoke system to achieve zero defects
What are “fail-safe procedures” and what is meant by poka-yoke?
Fail safe procedures are simple practices that help prevent errors. Poka-yokes are procedures that prevent mistakes from becoming defects
What is ISO 9000 and ISO 14000 certification? Why is it important to become ISO 9000 certified?
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
What is external benchmarking and what are the steps involved?
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
What is statistical quality control (SQC)?
Techniques designed to evaluate quality from a conformance point of view
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.
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.
What is the purpose of sampling? What can a sample be assumed to tell us about the actual distribution of the process in question?
Samples allow for statistical calculations. A sample can be assumed to tell us about the actual variation in output
What is meant by variability? Why is it impossible to have zero variability? What are upper and lower specification limits?
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
Why does Genichi Taguchi believe that the traditional view of the cost of variability is not accurate? Review Exhibits 13.1 and 13.2.
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
What is meant by the Six-Sigma limit?
When a part is designed, certain dimensions are specified to be within the upper and lower specification limits
What is the relationship between the Six-Sigma limit and a design process?
Usually trade offs need to be made when designing a process for making a part.
What is meant by the capability index? (Note: You are not required to understand the mathematics in calculating a capability index-scan this section.)
A capability index is used to measure how well our process is capable of producing relative to the design specifications
What is meant by process control? What is meant by statistical process control?
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
What are attributes? What is the difference between quality characteristics that are measurable and attributes?
Quality characteristics that are classified as either conforming or not conforming to a specification
What is a P-Chart?
A p=chart graphs attribute samples with upper and lower control limits
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
Mean, standard deviation, variation and sample standard deviation
What is the difference between sampling by variance and sampling by attributes?
Attributes are classified as either conforming, or non conforming. Whereas variance can be measured.
Why is it advantageous to use a small sample size when measuring variables?
Larger samples are more costly and the process might change if more samples are taken
How many samples should you take and how often? How should you set control limits?
Approximately four or five units. With about 25 samples to be analyzed.
What are the formulas involved in constructing process distribution charts? Review Formulas 13.8 to 13.11.
x add image
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.
x
What is acceptance sampling? Work through the solution to Example 13.5.
Used on existing goods to determine the percentage of products that conform to specifications
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.
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
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.
a = producers risk - the probability of rejecting a high quality lot b = consumers risk - the probability of accepting a low quality lot
What is an operating characteristics curve? What affects the shape of the curve? Study Exhibit 13.11
illustrate the probability
of accepting lots with varying percentages of defectives
Conformance quality
The degree to which the product or service design specifications are met
Quality at the source
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
dimensions of quality
Criteria by which quality is measured
