Quality Profile PDF

6/12/20 Quality Profile: MESA Products, Inc. — Designs, manufactures and installs cathodic protection systems that control the corrosion of metal surfaces in underground and submerged structures. — Implemented a comprehensive quality assurance specification for product acceptance, resulting in a sig...

6/12/20 Quality Profile: MESA Products, Inc. — Designs, manufactures and installs cathodic protection systems that control the corrosion of metal surfaces in underground and submerged structures. — Implemented a comprehensive quality assurance specification for product acceptance, resulting in a significant improvement in quality. — A variety of tools help to improve performance, including “lean” manufacturing, ISO 9000, and Baldrige. — A monthly balanced report card helps the company to review its performance and find ways to improve. Measuring and Controlling Quality Part 1 1 MANAGING FOR QUALITY AND PERFORMANCE EXCELLENCE, 9e, © 2014 Cengage Publishing 1 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 2 2 Quality Profile: Operations Management International Measurement for Quality Control — Operates and maintains more than 160 public and private — Measurement is the act of collecting data to quantify the values of product, service, process, and other business metrics. — Measures and indicators refer to the numerical results obtained from measurement. — The term indicator is often used for measurements that are not a direct or exclusive measure of performance. — Good measures should be SMART: Simple, Measurable, Actionable, Related (to customer and operational requirements), and Timely. sector wastewater and water treatment facilities — Key enablers for its Quality as a Business Strategy leadership system are the company’s Linkage of Process Model, which defines relationships among processes, and its Family of Measures, a balanced scorecard of 20 integrated metrics. — Team charters for improvement projects specify which of OMI’s more than 150 critical processes are involved, metrics for evaluation, costs, required resources, and other information vital to the success. © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 3 3 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 4 4 Example 8.1 – Quality Measurements for Pizza Delivery Figure 8.1 — Number of pizzas, by type per hour. — Order accuracy (as transmitted to the kitchen). — Number of pizzas rejected per number prepared. — Time to delivery. — Number of errors in collections. — Raw materials (dough, etc.) or finished pizzas inventory. © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 5 5 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 6 6 1 6/12/20 Common Quality Measurements Dashboards — … summaries of key performance measures, typically consisting of a small set of measures (five or six) that provide a quick summary of process performance. — Dashboards often use graphs, charts, and other visual aids to communicate key measures and alert workers and managers when performance is not where it should be. © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. — A unit of work is the output of a process or an individual process step. — A nonconformance is any defect or error associated with a unit of work. — In manufacturing we often use the term defect, and in service applications, we generally use the term error to describe a nonconformance. — A nonconforming unit of work is one that has one or more defects or errors. 7 7 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 8 8 Quality Measurements in Service Organizations Types of Quality Control Measures — An attribute measurement characterizes the presence or absence of nonconformances in a unit of work, or the number of nonconformances in a unit of work. — Attribute measurements often are collected by visual inspection and expressed as proportions and counts. — Variable measurements apply to dimensional quantities such as length, weight, and time, or any value on a continuous scale of measurement. — Variable measurements are generally expressed with statistical measures such as averages and standard deviations. © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 9 9 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 10 10 Attribute Measurements Example 8.2 — In manufacturing it is common to use the terms “proportion defective” and “defects per unit,” DPU, in these formulas. © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 11 11 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 12 12 2 6/12/20 Defect Classification Throughput Yield (TY) 1. Critical defect: A critical defect is one that judgment and experience indicate will surely result in hazardous or unsafe conditions for individuals using, maintaining, or depending on the product and will prevent proper performance of the product. 2. Major defect: A major defect is one not critical but likely to result in failure or to materially reduce the usability of the unit for its intended purpose. 3. Minor defect: A minor defect is one not likely to materially reduce the usability of the item for its intended purpose, nor to have any bearing on the effective use or operation of the unit. — …the number of units that have no nonconformances © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. Example 8.3 13 13 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 14 Rolled Throughput Yield (RTY) DPMO — …the proportion of conforming units that results from a series of process steps. — Mathematically, it is the product of the yields from each process step. — Example 8.4 — Defects per million opportunities (DPMO) = (Number of defects discovered)/(opportunities for error) × 1,000,000 — In services, the term often used as an analogy to dpmo is errors per million opportunities (epmo). — Example 8.5 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 15 15 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 16 16 Quality Cost Classification Cost of Quality Measures — Prevention — Cost of Quality (COQ) – the cost of avoiding poor — Investments made to keep nonconforming products from occurring quality, or costs incurred as a result of poor quality — Provides a basis for identifying improvement opportunities and success of improvement programs — COQ translates quality problems into the “language” of upper management—the language of money. © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 17 14 and reaching the customer — Appraisal — Associated with efforts to ensure conformance to requirements, generally through measurement and analysis of data to detect nonconformances — Internal failure — Costs of unsatisfactory quality found before the delivery of a product to the customer — External failure — Costs incurred after poor-quality products reach the customer 17 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 18 18 3 6/12/20 Measurement System Evaluation Cost of Quality Reporting Matrix — Observed variation in process output stems from the natural variation that occurs in the output itself as well as the measurement system. — The total observed variation in production output is the sum of the true process variation (which is what we actually want to measure) plus variation due to measurement: © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 19 19 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 20 20 Metrology Errors in Manual Inspection — …the science of measurement and is defined broadly as the collection of people, equipment, facilities, methods, and procedures used to assure the correctness or adequacy of measurements. — National and international trade requires weights and measures organizations that assure uniform and accurate measures used in trade, national or regional measurement standards laboratories, standards development organizations, and accredited and internationally recognized calibration and testing laboratories. — Complexity: The number of defects caught by an inspector decreases with more parts and less orderly arrangement. — Defect rate: When the product defect rate is low, inspectors tend to miss more defects than when the defect rate is higher. — Inspection rate: The inspector’s performance degrades rapidly as the inspection rate increases. © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 21 21 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 22 22 Accuracy and Precision Example 8.6 — Accuracy is defined as the difference between the true value and the observed average of a measurement. — Accuracy is measured as the amount of error in a measurement in proportion to the total size of the measurement. — Precision is defined as the closeness of repeated measurements to each other. — Precision relates to the variance of repeated measurements. © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 23 23 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 24 24 4 6/12/20 Calibration Accuracy versus Precision — …the process of verifying the capability and performance of an item of measuring and test equipment compared to traceable measurement standards. — The National Institute of Standards and Technology (NIST) maintains national measurement standards. — NIST calibrates the reference-level standards of those organizations requiring the highest level of accuracy. These organizations calibrate their own working-level standards and those of other metrology laboratories. These working-level standards are used to calibrate the measuring instruments used in the field. — Many organizations must ensure traceability by keeping records that their own measuring equipment has been calibrated by laboratories or testing facilities whose measurements can be related to appropriate standards. © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 25 25 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 26 26 Repeatability and Reproducibility Analysis R&R Studies 1. — Repeatability (equipment variation, EV) – variation in multiple measurements by an individual using the same instrument. — Reproducibility (appraiser variation, AV) - variation in the same measuring instrument used by different individuals. — A repeatability and reproducibility (R&R) study is a study of variation in a measurement system using statistical analysis. © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 2. 3. 4. 27 27 Select m operators and n parts Calibrate the measuring instrument Randomly measure each part by each operator for r trials Compute key statistics to quantify repeatability and reproducibility © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 28 28 Spreadsheet Template R&R Evaluation — A measurement system is adequate if R&R is low relative to the total variation, or equivalently, the part variation is much greater than the measurement system variation. — Under 10% error - OK — 10-30% error - may be OK — over 30% error - unacceptable © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 29 29 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 30 30 5 6/12/20 Process Capability Measurement Statistical Perspectives of R&R — Process capability is the ability of a process to produce — The proper way to express the results as a percentage of the total is to use the ratio of variances from formula (8.16), that is, output that conforms to specifications. — A process capability study is a carefully planned study designed to yield specific information about the performance of a process under specified operating conditions. Typical questions include: — Where is the process centered? — How much variability exists in the process? — Is the performance relative to specifications acceptable? — What proportion of output will be expected to meet specifications? — What factors contribute to variability? © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 31 31 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 32 Types of Process Capability Studies Example 8.9 Process characterization study - how a process performs under actual operating conditions Peak performance study - how a process performs under ideal conditions Component variability study - relative contribution of different sources of variation (e.g., process factors, measurement system) 2014 Cengage Learning. Reserved. May not be scanned, copied duplicated, or posted to a in publicly © 2011 Cengage Learning. All©Rights Reserved. May notAll beRights scanned, copied or duplicated, or posted to a or publicly accessible website, whole accessible or in part.. website, in wholeor in part. 33 33 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 34 34 Figure 8.7: Process Variation Histograms Figure 8.6 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 35 32 35 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 36 36 6 6/12/20 Process Capability Indexes © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. Example 8.11 37 37 38 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 38 Spreadsheet Template Process Performance Indexes — Alternative capability indexes - process performance indexes: Pp, Ppl, Ppu, and Ppk. — Mathematically, these are exactly the same as the process capability indexes Cp, Cpl, Cpu, and Cpk, but represent the actual, rather than ideal, performance in a noncontrolled environment. — In reality, this makes little sense; many experts do not recommend this because it is important to control a process and remove special causes in order to achieve high levels of quality and customer satisfaction. © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 39 39 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 40 Pre-Control Zones Pre-Control LTL — … a simple technique for ensuring that a process that has relatively good capability remains in control. — Divide the tolerance range into zones by setting two pre-control lines halfway between the center of the specification and the upper and lower specification limits. — The center zone, called the green zone, comprises onehalf of the total tolerance. — Between the pre-control lines and the specification limits are the yellow zones. — Outside the specification limits are the red zones. © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 41 40 Red Zone UTL Green Zone Red Zone nominal value Yellow Zones 41 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 42 42 7 6/12/20 Pre-Control Process Statistical Process Control (SPC) — At the start of a process, five consecutive parts must fall — … a methodology for monitoring a process to within the green zone. If not, the production setup must be reevaluated before the full production run can be started. — Once regular operations commence, sample one part: identify special causes of variation and signal the need to take corrective action when appropriate. — Control chart - a run chart to which two horizontal lines, called control limits are added: the upper control limit (UCL) and lower control limit (LCL) — If it falls within the green zone, production continues. — If it falls in a yellow zone, a second part is inspected. If the second part falls in the green zone, production can continue; if not, production should stop and a special cause should be investigated. — If any part falls in a red zone, then action should be taken. © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 43 43 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 44 44 Figure 8.14 Structure of a Control Chart Controlled Process — No points are outside control limits. — The number of points above and below the center line is about the same. — The points seem to fall randomly above and below the center line. — Most points, but not all, are near the center line, and only a few are close to the control limits. © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 45 45 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 46 46 Shift in Process Average Typical Out-of-Control Patterns — Point outside control limits — Sudden shift in process average — Cycles — Trends — Hugging the center line — Hugging the control limits © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 47 47 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 48 48 8 6/12/20 Identifying Shifts © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. Cycles 49 49 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 50 50 Trend © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. Hugging Center Line 51 51 © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 52 52 Hugging Control Limits © 2014 2011 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole wholeor or in part.. part. 53 53 9