tailieunhanh - Lecture Operations management (11/e): Chapter 10 - William J. Stevenson

Chapter 10 entitled 'Quality control' explains the elements of the control process, and how control charts can be used to monitor processes in order that they are performing in an acceptable manner. Quality control is a process that measures output relative to a standard and takes corrective action when output does not meet standard. Inspection can be used as part of an effort to improve process yield. One measure of process yield is the ratio of output of good product to the total output. | Quality Control McGraw-Hill/Irwin Copyright © 2012 by The McGraw-Hill Companies, Inc. All rights reserved. You should be able to: List and briefly explain the elements in the control process Explain how control charts are used to monitor a process, and the concepts that underlie their use Use and interpret control charts Perform run tests to check for nonrandomness in process output Assess process capability Student Slides 10- Quality Control A process that evaluates output relative to a standard and takes corrective action when output doesn’t meet standards If results are acceptable no further action is required Unacceptable results call for correction action Student Slides 10- Inspection An appraisal activity that compares goods or services to a standard Inspection issues: How much to inspect and how often At what points in the process to inspect Whether to inspect in a centralized or on-site location Whether to inspect attributes or variables Student Slides 10- Quality | Quality Control McGraw-Hill/Irwin Copyright © 2012 by The McGraw-Hill Companies, Inc. All rights reserved. You should be able to: List and briefly explain the elements in the control process Explain how control charts are used to monitor a process, and the concepts that underlie their use Use and interpret control charts Perform run tests to check for nonrandomness in process output Assess process capability Student Slides 10- Quality Control A process that evaluates output relative to a standard and takes corrective action when output doesn’t meet standards If results are acceptable no further action is required Unacceptable results call for correction action Student Slides 10- Inspection An appraisal activity that compares goods or services to a standard Inspection issues: How much to inspect and how often At what points in the process to inspect Whether to inspect in a centralized or on-site location Whether to inspect attributes or variables Student Slides 10- Quality control seeks Quality of Conformance A product or service conforms to specifications A tool used to help in this process: SPC Statistical evaluation of the output of a process Helps us to decide if a process is “in control” or if corrective action is needed Student Slides 10- Control Chart A time ordered plot of representative sample statistics obtained from an ongoing process (. sample means), used to distinguish between random and nonrandom variability Control limits The dividing lines between random and nonrandom deviations from the mean of the distribution Upper and lower control limits define the range of acceptable variation 10- Student Slides Variables generate data that are measured Mean control charts Used to monitor the central tendency of a process. “x- bar” charts Range control charts Used to monitor the process dispersion R charts 10- Student Slides Student Slides 10- Used to monitor the central tendency of a process Student Slides 10- Used to .