Workshop 5. Managing Quality. Kate Hughes & John Whiteley

Transcription

1 Workshop 5 Managing Quality Kate Hughes & John Whiteley

2 8-2 The various definitions of quality The transcendent approach views quality as synonymous with innate excellence. The manufacturing-based approach assumes quality is all about making or providing error-free products or services. The user-based approach assumes quality is all about providing products or services that are fit for their purpose. The product-based approach views quality as a precise and measurable set of characteristics. The value-based approach defines quality in terms of value.

3 8-3 Quality characteristics of goods and services Functionality - how well the product or service does the job for which it was intended. Appearance - aesthetic appeal, look, feel, sound and smell of the product or service. Reliability - consistency of product or services performance over time. Durability - the total useful life of the product or service. Recovery - the ease with which problems with the product or service can be rectified or resolved. Contact - the nature of the person-to-person contacts that take place.

4 8-4 Quality Meeting, or exceeding, customer requirements now and in the future.

5 8-5 Dimensions of Quality The Abilities Quality of Conformance QUALITY Field Service Quality of Design

6 8-6 Quality of Design Determined before the product is produced Determined by market research Translates the wishes of customers into specifications

7 8-7 Quality of Conformance Producing a product that meets the specifications

8 8-8 Abilities Availability (Continuity of service to customers) Reliability (Length of time that a product can be used before it fails) Maintainability (Restoration of the product or service once it has failed)

9 Different Types of Quality (Figure 8.1) 8-9 Customer satisfaction Quality of design Quality of conformance Availability Field service Quality of market research Quality of concept Quality of specification Technology Employees Management Reliability Maintainability Logistical support Promptness Competence Integrity

10 8-10 Philip Crosby W. Edwards Deming Armand Feigenbaum Kaoru Ishikawa Joseph Juran Genichi Taguchi The quality gurus Quality is free - the optimum is zero defects. Deming s 14 points. How to use statistics. Total quality control. Quality circles and cause and effect diagrams. Quality as fitness for use, rather than conformance to specification. Loss function. Minimize variation.

11 8-11 Reasons for Failure in Quality Improvement Programs Focus on short-term financial gains Blame the employee syndrome Belief in tradeoffs in quality (don t believe quality is free ) Management interference with true teamwork Sloppy procedures and processes

12 Quality Control and Improvement Schroeder Operations Management Chapter 9

13 8-13 Designing of Quality Control Systems Processes and internal customers. Critical points and guidelines in identifying them. Steps in designing QC systems.

14 8-14 Steps in Designing QC Systems Identify critical points Decide on the type of measurement (variable versus attribute) Decide on the amount of inspection to be used. Decide who should do the inspection

15 8-15 Process Quality Control Basic assumptions (tenets) of Process Quality Control: Every process has random variation in it. Production processes are not usually found in a state of control. State of Control ; what does it mean?

16 8-16 Process Quality Control Purpose of Statistical Process Control (SPC) SPC Charts (See figures 9.1 and 9.2) Types of SPC charts: Attribute control charts Variable control charts Using control (and interpreting) control charts

17 8-17 Attribute and variable measures of quality Attributes Variable s Defective or not defective? Light bulb works or does not work. Number of defects in a turbine blade. Measured on a continuous scale. Diameter of bulb. Length of bar.

18 8-18 Process Control Chart (Figure y 9.1) Average + 3 standard deviations Upper control limit (UCL) Quality measurement average Center line (CL) Average - 3 standard deviations Lower control limit (LCL) Time x

19 8-19 Quality Control Chart (Figure 9.2) UCL Stop the process; look for assignable cause CL LCL Stop the process; look for assignable cause Sample

20 8-20 Statistical process control UCL C/L LCL Alternating and erratic behaviour - investigate UCL C/L LCL Two points near control limit - investigate UCL C/L LCL Apparent trend in one direction - investigate UCL C/L LCL Suspiciously average behaviour - investigate UCL C/L LCL Five points one side of centre line - investigate UCL C/L LCL Sudden change in level - investigate

21 8-21 Continuous Improvement Input-output charts Process flow charts Scatter Charts Pareto analysis Cause-and-effect (fish-bone) diagrams Why- why analysis Process capability charts See Slack Operations Management pages 663 to 673

22 # of Defectives Percentage 8-22 Pareto Diagram (Figure 9.3) % % % 60.0% 40.0% 20.0% 0 0.0% Loose connections Cracked connectors Fitting burrs Improper torque O-rings missing

23 8-23 Cause-and-effect (Fish-bone) diagram (Figure 9.4) Content Workers Material connectors Small Size Large Nuts Training Size Measuring tools Judgment Knowledge Measurement Errors Fatigue Hose Surface defect Experience Inspector Wear Torque Adjustment Loose connections Inspection Training Tools Air pressure

24 Process-Flow Analysis Chapter 7

25 7-25 Outline Systems Thinking The Process View of Business Flowchart Analysis Materials-Flow Analysis Using Process-Flow Analysis Business Process Reengineering (BPR)

26 7-26 Steps in process flow chart analysis Select a process Form a team or individual as the project leader Decide on the objectives of the analysis Define customers and suppliers Describe the existing transformation process Develop improved process design Gain management approval of the improved design Implement the new process design

27 CUSTOMER CSA COMPUTER Ring loan company Provide status information Provide credit information Size of loan required Assess offer Answer call Initial screening Credit assessment Size of borrowing Explain costs and terms Assess call queue length Screening questions On-line credit check Assess risk, calculate rate Accept or reject offer Agree release/ Set up payment payment details instructions

28 7-28 Flow Diagrams - Example Sink 1 Cup Kettle

29 7-29 Symbols for Flow-Process Chart Operation (a task or work activity) Inspection (an inspection of the product for quantity or quality) Transportation (a movement of material from one point to another) Storage (an inventory or storage of materials awaiting the next operation) Delay (a delay in the sequence of operations)

30 7-30 Flow Process Chart Symbols (II) Operation where the item being processed is modified or changed Transport Permanent Storage Delay/Temp Storage where the item being processed is moved where the item being processed is put into permanent storage where the item being processed is delayed and/or put into temporary storage Inspection where the item being processed is checked for quality or quantity

31 7-31 Flow Process Charts - Example Activity Time Distance (seconds) (metres) Take kettle to tap 4 3 Put water in 5 kettle Take kettle back 4 3 Switch on kettle 2 Wait for water to 120 boil Take kettle to cup 3 2

32 7-32 Questions to Ask in PFA What does the customer need?, operations are necessary? Can some operations be eliminated, combined, or simplified?. Who is performing the job? Can the operation be redesigned to use less skill or less labour? Can operations be combined to enrich jobs?. Where is each operation conducted? Can layout be improved?. When is each operation performed? Is there excessive delay or storage? Are some operations creating bottlenecks?.. How is the operation done? Can better methods, procedures, or equipment be used?.

33 7-33 Cycle of Service for an Airline Critical Incident analysis Leaves Airport Customer requests schedule information Makes reservation Receive Baggage Departs Plane Receives in-flight service Arrives at airport Checks baggage and checks in for flight Boards aircraft Receives boarding pass Proceeds to gate and security check

34 Tutorial Exercise 8-34 Draw a Fishbone diagram and use it to guide you in identifying the major problems occurring in the order fulfilment process in the St James Hospital and Lucas Engineering Systems case study Once you have identified what you believe to be the major problem create a new fishbone diagram with it as the head. Present your strategy to solve each of the fishbones (identified problems) to the class