Materi Training Quality_Tools dengan format ppt
- 1. Seven Quality Tools Presented by: M. Aschner
- 2. Objective Present an overview of Seven Quality Tools Present an overview of Seven Quality Tools Address purpose and applications Address purpose and applications Highlight benefits Highlight benefits
- 3. The Deming Chain The Deming Chain Improve Quality Improve Quality Decrease Costs Decrease Costs Improve Productivity Improve Productivity Decrease Price Decrease Price Increase Market Increase Market Stay in Business Stay in Business Provide More Jobs Provide More Jobs Return on Investment Return on Investment Why Do This?
- 4. Six Problem Solving Steps Identify Identify recognize the symptoms Define Define Agree on the problem and set boundaries Investigate Investigate Collect data Analyze Analyze Use quality tools to aid Solve Solve Develop the solution and implement Confirm Confirm Follow up to ensure that the solution is effective
- 5. Seven Quality Tools Cause and Effect Diagrams Cause and Effect Diagrams Flow Charts Flow Charts Checksheets Checksheets Histograms Histograms Pareto Charts Pareto Charts Control Charts Control Charts Scatter Diagrams Scatter Diagrams
- 6. Quality Tool Brainstorming Rules Rules • Diverse group Diverse group • Go around room and get input from all – one Go around room and get input from all – one idea per turn idea per turn • Continue until ideas are exhausted Continue until ideas are exhausted • No criticism No criticism • Group ideas that go together Group ideas that go together • Look for answers Look for answers
- 7. Quality Tool Cause and Effect Diagrams
- 8. Fishbone Diagram Purpose: Purpose: Graphical representation Graphical representation of the trail leading to the root cause of of the trail leading to the root cause of a problem a problem How is it done? How is it done? • Decide which quality characteristic, Decide which quality characteristic, outcome or effect you want to outcome or effect you want to examine (may use Pareto chart) examine (may use Pareto chart) • Backbone –draw straight line Backbone –draw straight line • Ribs – categories Ribs – categories • Medium size bones –secondary Medium size bones –secondary causes causes • Small bones – root causes Small bones – root causes
- 9. Cause & Effect Diagrams Benefits: Benefits: Breaks problems down into bite-size pieces to find root cause Breaks problems down into bite-size pieces to find root cause Fosters team work Fosters team work Common understanding of factors causing the problem Common understanding of factors causing the problem Road map to verify picture of the process Road map to verify picture of the process Follows brainstorming relationship Follows brainstorming relationship
- 10. Cause & Effect Diagrams Sample Incorrect shipping documents Manpower Materials Methods Machine Environment Keyboard sticks Wrong source info Wrong purchase order Typos Source info incorrect Dyslexic Transposition Didn’t follow proc. P o o r t r a i n i n g Glare on display Temp. No procedure No communications No training Software problem Corrupt data
- 12. Flow Charts Purpose: Purpose: Visual illustration of the sequence of operations required to Visual illustration of the sequence of operations required to complete a task complete a task Schematic drawing of the process to measure or improve. Schematic drawing of the process to measure or improve. Starting point for process improvement Starting point for process improvement Potential weakness in the process are made visual. Potential weakness in the process are made visual. Picture of Picture of process as it process as it should should be. be. Benefits: Benefits: Identify process improvements Identify process improvements Understand the process Understand the process Shows duplicated effort and other non-value-added steps Shows duplicated effort and other non-value-added steps Clarify working relationships between people and organizations Clarify working relationships between people and organizations Target specific steps in the process for improvement. Target specific steps in the process for improvement.
- 13. Flow Charts Top Down Benefits Benefits • Simplest of all Simplest of all flowcharts flowcharts • Used for planning new Used for planning new processes or examining processes or examining existing one existing one • Keep people focused on Keep people focused on the whole process the whole process How is it done? How is it done? • List major steps List major steps • Write them across top of Write them across top of the chart the chart • List sub-steps under each List sub-steps under each in order they occur in order they occur Problem report Hardware return Failure analysis Measure Customer input Stress analysis Heat transfer analysis Life analysis Substantiation Analyze Hardware procurement Customer coordination Compliance verification Documentation FAA approval Improve Fleet leader reports Service reports Operational statistics Control
- 14. Flow charts Linear Benefits Benefits Show what actually happens at Show what actually happens at each step in the process each step in the process Show what happens when non- Show what happens when non- standard events occur standard events occur Graphically display processes to Graphically display processes to identify redundancies and other identify redundancies and other wasted effort wasted effort How is it done? How is it done? Write the process step inside Write the process step inside each symbol each symbol Connect the Symbols with Connect the Symbols with arrows showing the direction of arrows showing the direction of flow flow Toolbox
- 15. Quality Tool Sample Linear Flow 1- Fleet Analysis utilizes data warehouse reports to create and distribute a selection matrix. 2 - Other Groups compile data as determined by FRB. 3 - FRB meets to analyze data. 4 - FRB selects candidate problems for additional investigation. 5 - Action Assignee performs detail analysis of failure. Requests failure analysis as needed. 6 - Action Assignee documents investigation findings. 7 - Action Assignee reports investigation results to FRB. 8 - Fleet Analysis monitors failed item to ensure failure has been corrected. Still failing? 9 - FRB Categorize Failure: Workmanship, component, material, maintenance, or design. Also fleet wide or RSU. 10 - FRB determines required corrective action - i.e. QAM or supplier corrective action. 11 - Fleet Analysis monitors failure to ensure corrective action is effective. Still failing? No Yes Yes END No Start
- 17. Checksheets Purpose: Purpose: Tool for collecting and Tool for collecting and organizing measured or counted organizing measured or counted data data Data collected can be used as Data collected can be used as input data for other quality tools input data for other quality tools Benefits: Benefits: Collect data in a systematic and Collect data in a systematic and organized manner organized manner To determine source of problem To determine source of problem To facilitate classification of To facilitate classification of data (stratification) data (stratification)
- 19. Histograms Purpose: Purpose: To determine the spread or variation of To determine the spread or variation of a set of data points in a graphical a set of data points in a graphical form form How is it done?: How is it done?: Collect data, 50-100 data point Collect data, 50-100 data point Determine the range of the data Determine the range of the data Calculate the size of the class interval Calculate the size of the class interval Divide data points into classes Divide data points into classes Determine the class boundary Determine the class boundary Count # of data points in each class Count # of data points in each class Draw the histogram Draw the histogram Stable process, exhibiting bell shape
- 20. Histograms Benefits: • Allows you to understand at a glance the variation that exists in a process • The shape of the histogram will show process behavior • Often, it will tell you to dig deeper for otherwise unseen causes of variation. • The shape and size of the dispersion will help identify otherwise hidden sources of variation • Used to determine the capability of a process • Starting point for the improvement process
- 21. Quality Control Tool Pareto Charts
- 22. Pareto Charts Purpose: Purpose: Prioritize problems. Prioritize problems. How is it done? How is it done? Create a preliminary list of Create a preliminary list of problem classifications. problem classifications. Tally the occurrences in each Tally the occurrences in each problem classification. problem classification. Arrange each classification in Arrange each classification in order from highest to lowest order from highest to lowest Construct the bar chart Construct the bar chart
- 23. Pareto Charts Benefits: Benefits: Pareto analysis helps Pareto analysis helps graphically display graphically display results so the results so the significant few significant few problems emerge problems emerge from the general from the general background background It tells you what to It tells you what to work on first work on first 0 20 40 60 80 100 120 Quantity Defects 104 42 20 14 10 6 4 Dent Scratch Hole Others Crack Stain Gap
- 24. Pareto Charts Weighted Pareto Weighted Pareto charts use Weighted Pareto charts use the quantity of defects the quantity of defects multiplied by their cost to multiplied by their cost to determine the order. determine the order. 0 100 200 300 400 500 600 700 800 900 Weighted Cost Weighted cost 800 208 100 80 42 14 6 Gap Dent Hole Crack Scratch Others Stain Defect Total Cost Weighted cost Gap 4 200 800 Dent 104 2 208 Hole 20 5 100 Crack 10 8 80 Scratch 42 1 42 Others 14 1 14 Stain 6 1 6 Pareto Charts
- 25. Quality Control Tool Control Charts
- 26. Control Charts Purpose: Purpose: The primary purpose of a control chart is to predict The primary purpose of a control chart is to predict expected product outcome. expected product outcome. Benefits: Benefits: Predict process out of control and out of Predict process out of control and out of specification limits specification limits Distinguish between specific, identifiable causes of Distinguish between specific, identifiable causes of variation variation Can be used for statistical process control Can be used for statistical process control
- 27. Control Charts Strategy for eliminating assignable-cause variation: Strategy for eliminating assignable-cause variation: Get timely data so that you see the effect of the Get timely data so that you see the effect of the assignable cause soon after it occurs. assignable cause soon after it occurs. As soon as you see something that indicates that an As soon as you see something that indicates that an assignable cause of variation has happened, search assignable cause of variation has happened, search for the cause. for the cause. Change tools to compensate for the assignable cause. Change tools to compensate for the assignable cause. Strategy for reducing common-cause variation: Strategy for reducing common-cause variation: Do not attempt to explain the difference between any Do not attempt to explain the difference between any of the values or data points produced by a stable of the values or data points produced by a stable system in control. system in control. Reducing common-cause variation usually requires Reducing common-cause variation usually requires making fundamental changes in your making fundamental changes in your process process
- 28. Control Charts Control Chart Decision Tree Control Chart Decision Tree Determine Sample size (n) Variable or Attribute Data Variable is measured on a continuous scale Attribute is occurrences in n observations Determine if sample size is constant or changing
- 29. Control Charts Start Variable data n >10 n = 2 to 10 X bar , R X bar, S n = 1 IX, Moving Range Percent data Count data Constant n Constant n Changing n Changing n p (fraction defective) or np (number def. Per sample p c (defects per sample or u defects per unit u Control Chart Decision Tree A t t r i b u t e D a t a
- 30. Control Charts What does it look like? What does it look like? o Adding the element of time Adding the element of time will help clarify your will help clarify your understanding of the causes understanding of the causes of variation in the processes. of variation in the processes. o A run chart is a line graph A run chart is a line graph of data points organized in of data points organized in time sequence and centered time sequence and centered on the median data value. on the median data value.
- 31. Control Charts Individual X charts How is it done? How is it done? The data must have a normal distribution (bell curve). The data must have a normal distribution (bell curve). Have 20 or more data points. Fifteen is the absolute minimum. Have 20 or more data points. Fifteen is the absolute minimum. List the data points in time order. List the data points in time order. Determine the range Determine the range between each of the consecutive data points. between each of the consecutive data points. Find the mean or average of the data point values. Find the mean or average of the data point values. Calculate the control limits (three standard deviations) Calculate the control limits (three standard deviations) Set up the scales for your control chart. Set up the scales for your control chart. Draw a solid line representing the data mean. Draw a solid line representing the data mean. Draw the upper and lower control limits. Draw the upper and lower control limits. Plot the data points in time sequence. Plot the data points in time sequence.
- 32. Control Charts Next, look at the upper and lower Next, look at the upper and lower control limits. If your process is in control limits. If your process is in control, 99.73% of all the data control, 99.73% of all the data points will be inside those lines. points will be inside those lines. The upper and lower control limits The upper and lower control limits represent three standard deviations represent three standard deviations on either side of the mean. on either side of the mean. Divide the distance between the Divide the distance between the centerline and the upper control centerline and the upper control limit into three equal zones limit into three equal zones representing three standard representing three standard deviations. deviations.
- 33. Control Charts Search for trends: Search for trends: Two out of three consecutive Two out of three consecutive points are in zone points are in zone “ “C C” ” Four out of five consecutive Four out of five consecutive points on the same side of points on the same side of the center line are on zone the center line are on zone “ “B B” ” or or “ “C C” ” Only one of 10 consecutive Only one of 10 consecutive points is in zone points is in zone “ “A A” ”
- 34. Control Charts Basic Control Charts Basic Control Charts interpretation rules interpretation rules: : Specials are any points above the UCL or below the LCL A Run violation is seven or more consecutive points above or below the center (20-25 plot points) A trend violation is any upward or downward movement of five or more consecutive points or drifts of seven or more points (10-20 plot points) A 1-in-20 violation is more than one point in twenty consecutive points close to the center line
- 35. Quality Control Tool Scatter Diagrams
- 36. Scatter Diagrams Purpose: Purpose: To identify the correlations that might exist between a quality characteristic and a factor that might be driving it A scatter diagram shows the correlation between two variables in a process. These variables could be a Critical To Quality (CTQ) characteristic and a factor affecting it two factors affecting a CTQ or two related quality characteristics. Dots representing data points are scattered on the diagram. The extent to which the dots cluster together in a line across the diagram shows the strength with which the two factors are related.
- 37. Scatter Diagrams How is it done?: How is it done?: • Decide which paired factors you want to examine. Both factors must be measurable on some incremental linear scale. • Collect 30 to 100 paired data points. • Find the highest and lowest value for both variables. • Draw the vertical (y) and horizontal (x) axes of a graph. • Plot the data • Title the diagram The shape that the cluster of dots takes will tell you something about the relationship between the two variables that you tested.
- 38. Scatter Diagrams • If the variables are correlated, when one changes the other probably also changes. • Dots that look like they are trying to form a line are strongly correlated. • Sometimes the scatter plot may show little correlation when all the data are considered at once. Stratifying the data, that is, breaking it into two or more groups based on some difference such as the equipment used, the time of day, some variation in materials or differences in the people involved, may show surprising results
- 39. Scatter Diagrams • You may occasionally get scatter diagrams that look boomerang- or banana-shaped. To analyze the strength of the correlation, divide the scatter plot into two sections. Treat each half separately in your analysis Benefits: • Helps identify and test probable causes. • By knowing which elements of your process are related and how they are related, you will know what to control or what to vary to affect a quality characteristic.
Editor's Notes
- #1: Introduction: 22 years as quality professional Certified Quality Engineer Certified SW Quality Engineer RAB trained auditor ASQ LI Section Chairman & programs coordinator
- #3: Why are we doing this? Because companies with quality programs make more profit. Return on investment is increased.
- #4: Identify – must be hands on to recognize the problem Define – Knowing that there is a problem, set up the conditions to sole it Investigate – perform tests and collect data so you can react to facts. Seat of the pants decision making is forbidden. Analyze – Use the quality tools to aid in understanding the problem Solve – Using the data and quality tools come up with the solution and implement it. When implementing the solution it is imperative that the management monitor the implementation at every step. People are resistant to change and must be hounded to ensure it is implemented as envisioned. This is why it is good to have employees involved in the process integral to the solution. It is also the idea behind suggestion programs. Confirm – Follow up!
- #5: Cause and Effect diagrams – Ishikawa diagrams of Fishbone diagrams Top down and Linear flow Simple check sheets which lead to Histograms Histograms leading to Pareto charts Pareto charts Scatter charts All of these tools are related
- #6: Brainstorming Rules Best in a diverse group of people Record ideas in a visible way – black board, easel… All ideas are valid Go around room until ideas are exhausted Discuss ideas
- #8: Man, material, machine, method, environment, measurement (sometimes) Separate various causes into identifiable groups Good basis for showing you where data should be collected
- #9: Brainstorm the causes under each category Sometimes just performing the fishbone diagram will enable the problem to be resolved by understanding
- #17: In the top chart we see two operators and two machines. In the morning both operators and both machines seem to be working well. However in the afternoon we see both operators are more prone to defects and the machine two is very prone to problems. We conclude there may be some operator fatigue involved AND that there is some condition on machine two that needs to be investigated. Look for something that affects on machine but not the other like sun glare… Conditions Workers Material
- #19: Displays distributions Remember the bell curve from school… a few Fs many Bs and Cs a few As.
- #20: A histogram is a picture of the statistical variation in your process. Not only can histograms help you know which processes need improvement they can also help you track that improvement This is a process that has too much variation to meet specifications no matter how it is centered. Action must be taken to reduce variation in this process
- #22: Column graph in rank order 80% of problems related by 20% of causes The vital few and the trivial many – Dr. Juran Identifies problems to be worked first
- #23: Conclusion: We need to concentrate on dents Its good that there are not many gaps because they are very expensive. TRAP This works sometimes but another type of chart is frequently better
- #24: Defects times cost Gap becomes the obvious place to start corrective actions Costs more than all others put together!!!
- #25: Now that you know which area to look from the Cause and Effect Diagrams Brainstorming Flow Charts Check sheets Histograms Pareto Charts you need some basic information on how to monitor processes.
- #27: Assignable cause – also known as special cause Specific problems Need to be identified quickly to stabilize process Dull/broken drill, incorrect tool… Common cause Normal Hard to eliminate Fixed by changes to process Example is run out in a drill press.
- #28: There are many types of control charts. Based on the type of data you collect there is a chart for you. Make decisions based on type of data and sample size. VARIABLE CHARTS X bar using R - small sample size – 3 to 5 <7 controls X bar using S – large sample size - >7 IndX using MR - when rational subgroups are not possible ATTRIBUTE CHARTS P chart – sample is large and changeable Np chart - sample is large constant C chart – constant unit – one item – defects per unit U chart – changeable average defects per unit
- #30: The patterns in the run chart can help you find where to look for assignable causes of variation. A Run Chart can show you trends or help pinpoint unusual events.
- #33: Trends indicate that the process may not be in control One point beyond 3 sigma 2 of 3 points between 2 and 3 sigma 4 of 5 points above2 sigma 8 points in a row in any zone
- #36: Shows relationship between two variables
- #39: To control variation in any process -it is absolutely essential that you understand which causes are generating which effects.