To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Quality Management OPIM 310-Lecture #10 Instructor: Jose Cruz

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. “The degree of excellence of a thing” (Webster’s Dictionary) “The degree of excellence of a thing” (Webster’s Dictionary) “The totality of features and characteristics that satisfy needs” (ASQ) “The totality of features and characteristics that satisfy needs” (ASQ) Fitness for use Fitness for use Quality of design Quality of design What Is Quality?

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Dimensions of Quality 1.Performance Basic operating characteristics Basic operating characteristics 2.Features “Extra” items added to basic features “Extra” items added to basic features 3.Reliability Probability product will operate over time Probability product will operate over time

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Dimensions of Quality 4.Conformance Meeting pre-established standards Meeting pre-established standards 5.Durability Life span before replacement Life span before replacement 6.Serviceability Ease of getting repairs, speed & competence of repairs Ease of getting repairs, speed & competence of repairs

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Dimensions of Quality 7.Aesthetics Look, feel, sound, smell or taste Look, feel, sound, smell or taste 8.Safety Freedom from injury or harm Freedom from injury or harm 9.Other perceptions Subjective perceptions based on brand name, advertising, etc Subjective perceptions based on brand name, advertising, etc

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. 1.Time & Timeliness Customer waiting time, completed on time Customer waiting time, completed on time 2.Completeness Customer gets all they asked for Customer gets all they asked for 3.Courtesy Treatment by employees Treatment by employees Service Quality

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. 4.Consistency Same level of service for all customers Same level of service for all customers 5.Accessibility & Convenience Ease of obtaining service Ease of obtaining service 6.Accuracy Performed right every time Performed right every time 7.Responsiveness Reactions to unusual situations Reactions to unusual situations Service Quality

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Quality of Conformance Ensuring product or service produced according to design Ensuring product or service produced according to design Depends on Depends on Design of production process Design of production process Performance of machinery Performance of machinery Materials Materials Training Training

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Fitness for Consumer Use Fitness for Consumer Use Producer’s Perspective Consumer’s Perspective Quality of Conformance Conformance to specifications Cost Quality of Design Quality characteristics Price Marketing Production The Meaning of Quality Figure 14.1 The Meaning of Quality

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. The Deming Wheel (or PDCA Cycle) 1. Plan Identify the problem and develop the plan for improvement. 2. Do Implement the plan on a test basis. 3. Study/Check Assess the plan; is it working? 4. Act Institutionalize improvement; continue the cycle. Figure 14.2

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Total Quality Management 1.Customer defined quality 2.Top management leadership 3.Quality as a strategic issue 4.All employees responsible for quality 5.Continuous improvement 6.Shared problem solving 7.Statistical quality control 8.Training & education for all employees

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. TQM Throughout the Organization Marketing, sales, research Marketing, sales, research Engineering Engineering Purchasing Purchasing Human resources Human resources Management Management Packing, storing, shipping Packing, storing, shipping After-sale support After-sale support

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Strategic Implications of TQM Quality is key to effective strategy Quality is key to effective strategy Clear strategic goal, vision, mission Clear strategic goal, vision, mission High quality goals High quality goals Operational plans & policies Operational plans & policies Feedback mechanism Feedback mechanism Strong leadership Strong leadership

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Cost of Quality Cost of achieving good quality Cost of achieving good quality Prevention Prevention Planning, Product design, Process, Training, Information Planning, Product design, Process, Training, Information Appraisal Appraisal Inspection and testing, Test equipment, Operator Inspection and testing, Test equipment, Operator

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Cost of Quality Cost of poor quality Cost of poor quality Internal failure costs Internal failure costs Scrap, Rework, Process failure, Process downtime, Price- downgrading Scrap, Rework, Process failure, Process downtime, Price- downgrading External failure costs External failure costs Customer complaints, Product return, Warranty, Product liability, Lost sales Customer complaints, Product return, Warranty, Product liability, Lost sales

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Measuring and Reporting Quality Labor index Labor index Quality cost / labor hours Quality cost / labor hours Cost index Cost index Quality cost / manufacturing cost Quality cost / manufacturing cost Sales index Sales index Quality cost / sales Quality cost / sales Production index Production index Quality cost / units produced Quality cost / units produced

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Quality Costs and Index YEAR Quality Costs Prevention$ 27,00041,50074,600112,300 Appraisal155,000122,500113,400107,000 Internal failure386,400469,200347,800219,100 External failure242,000196,000103,500106,000 Total$ 810,400829,200639,300544,400 Accounting Measures Sales$ 4,360,0004,450,0005,050,0005,190,000 Mfg costs1,760,0001,810,0001,880,0001,890,000

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Quality Costs and Index Quality index = (100) total quality costs base Quality cost per sale = = $810,400(100) 4,360,000 QUALITYQUALITY MANUFACTURING YEARSALES INDEXCOST INDEX

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Quality–Cost Relationship Increased prevention costs lead to decreased failure costs Increased prevention costs lead to decreased failure costs Improved quality leads to increased sales and market share Improved quality leads to increased sales and market share Quality improvement at the design stage Quality improvement at the design stage Higher quality products can command higher prices Higher quality products can command higher prices

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Quality and Productivity Quality improvement reduces inputs Quality improvement reduces inputs Fewer defects increase output Fewer defects increase output Productivity = Productivity =outputinput

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Measuring Yield and Productivity where Y= yield I= number units started in production % G= percentage good units % R= percentage of defective units reworked Yield =(total input) (% good units) + (total input)(1 - % good units)(% reworked) Y = (I)(%G) + (I)(1 - %G)(%R)

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Product Yield Start 100 motors per day 80% are good 50% of poor quality units can be reworked Yield= (I)(%G) + (I)(1 - %G)(%R) Y= 100(0.80) + 100( )(0.50) = 90 motors Y= 100(0.90) + 100( )(0.50) = 95 motors If product quality is increased to 90% good, Example 14.2

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Product Cost Product cost = (K d )(I) + (K r )(R) Y Product cost = (direct manufacturing cost per unit)(input) + (rework cost per unit)(reworked units) yieldwhere K d = direct manufacturing cost per unit I= input K r = rework cost per unit R= reworked units Y= yield

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Product Cost Direct mfg cost = $30, Rework cost = $ motors started, 20% defective 50% of defective motors can be reworked Product cost = (K d )(I) + (K r )(R) Y Product cost = = $34.67 per motor ($30)(100) + ($12)(10) 90 motors The manufacturing cost after quality improvement is Product cost = = $32.21 per motor ($30)(100) + ($12)(5) 95 motors Example 14.3

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Multistage Product Yield Y = (I) (%g 1 )(%g 2 )...(%g n ) where I= input batch size %g i = percent good at stage i

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Multistage Process Yield Start with 100 motors AVERAGE PERCENTAGE STAGE GOOD QUALITY Y= (I) (%g 1 )(%g 2 )...(%g n ) = (100)(0.93)(0.95)(0.97)(0.92) Y= 78.8 motors Solve for I I = = = motors Y (%g 1 )(%g 2 )...(%g n ) 100(0.93)(0.95)(0.97)(0.92) Example 14.4

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Quality Productivity Ratio (QPR) Includes productivity and quality costs Includes productivity and quality costs Increases Increases if processing or rework costs decrease if processing or rework costs decrease if process yield increases if process yield increases QPR = (100) Good-quality units (input)(processing cost) + (defective units)(rework cost)

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. QPR Example Direct cost = $30/unit Rework cost = $12/unit Start with 100 motors per day 80% are good, 50% of defective units can be reworked Company studies 4 changes 1.Increase production to 200 units/day 2.Cut processing cost to $26 & rework cost to $10 3.Increase yield to 95% 4.Combine 2 and 3

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. QPR Example Direct cost = $30/unit Rework cost = $12/unit Start with 100 motors per day 80% are good, 50% of defective units can be reworked Base case: QPR = (100) = (100)($30) + (10)($12) Case 1: Increase input to capacity of 200 units QPR = (100) = (200)($30) + (20)($12)

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. QPR Example Case 3: Increase initial good-quality to 95% QPR = (100) = (100)($30) + (2.5)($12) Case 4: Decrease costs and increase initial good-quality QPR = (100) = (100)($26) + (2.5)($10) Case 2: Reduce processing cost to $26 and rework to $10 QPR = (100) = (100)($26) + (10)($10)

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Pareto Chart NUMBER OF CAUSEDEFECTSPERCENTAGE Poor design8064% Wrong part dimensions1613 Defective parts1210 Incorrect machine calibration76 Operator errors43 Defective material32 Surface abrasions %

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Pareto Chart Percent from each cause Causes of poor quality Machine calibrations Defective parts Wrong dimensions Poor Design Operator errors Defective materials Surface abrasions (64) (13) (10) (6) (3) (2)(2)

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Flow Chart Operation Decision Start/ Finish Operation Decision

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Check Sheet 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 |

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Histogram

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Scatter Diagram Y X

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Control Chart Sample number Number of defects UCL = LCL = 1.99 c = 12.67

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Cause-and-Effect Diagram Quality Problem Quality Problem Out of adjustment Tooling problems Old / worn Machines Faulty testing equipment testing equipment Incorrect specifications Improper methods Measurement Poor supervision Lack of concentration Inadequate training Human Deficiencies in product design Ineffective quality management Poor process design Process Inaccuratetemperaturecontrol Dust and Dirt Environment Defective from vendor Not to specifications Material- handling problems Materials Figure 14.6

To Accompany Russell and Taylor, Operations Management, 4th Edition,  2003 Prentice-Hall, Inc. All rights reserved. Six Sigma Quality There are five steps in applying Six Sigma to a project. Identify the "critical to quality characteristics" (CTQ) that will have the most impact on quality. Identifying the internal processes that affect CTQ and measuring the defects that result from them. Analyzing why defects are generated by identifying the variables most likely to create process variation. Confirming the variables, quantifying their effect on CTQ, identifying the maximum acceptable ranges of the variables and validating a system for measuring deviations of them. Finally, there is control, which means tools are put into place to assure that under the modified process, the variables remain within the acceptable ranges.