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The 7 Basic Quality Tools

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1 The 7 Basic Quality Tools
Michele Cano All of these are to make data visible

2 Agenda Introductions The 7 Basic Tools Exercises Break
The 7 Basic Tools continued Group Discussions

3 What are they? The seven basic tools according to Ishikawa are:
Check sheets Flow charts Graphs & Histograms Pareto diagram Cause and effect diagram Scatter diagram Control chart

4 Why use tools? To make data visible Measure Improve
In order to ensure the effectiveness of the what an organisation does, you must measure record and analyse, allowing you to maintain or hopefully improve on the current situation. In order to maximise the results and minimise the effort there are a number of tools which can be used.

5 1.Check sheets What is a check sheet?
A form or sheet used to record data. A check sheet or Tally sheet is a form or sheet used to Record data in a way that is easy to use and analyse. A check sheet is also a useful aide-mémoire to ensure all activities have been performed. They should only include the appropriate check information and should be simple to use. There are many different types of check sheets serving different functions. However, they usually involve making checkmarks on a sheet to count the number of times something happens as it happens.

6 Function of Check Sheets
According to Ishikawa 1982, check sheets have the following functions: Production Process distribution checks Defective item checks Defective location checks Defective cause checks Check-up confirmation checks Others

7 Example of a simple check sheet. (for car valet operation)
Car type Car registration Ford Focus W357 PHR Interior vacuumed Upholstery cleaned Dash board cleaned De odorised Body washed Washed waxed & Polished Under car washed Wheels washed Tyres blacked Comments: Front bumper badly scratched on delivery, this can not be covered Performed / Checked by J Bloggs Date 2 May 2008

8 Example of a simple process check sheet. (attributes)
Model XYZC217 Batch failures 1 2 3 4 5 6 7 8 9 10 Power up Boot up Sink test Case damage Keyboard damage Monitor damaged Bundled s/w included Checked by pj am jj [j lm rm

9 Flowcharts PROCESS MAPPING
Process mapping is an essential first step. It identifies all of the process activities, sequence and responsibilities. This can either be in a written format, or as a flowchart.

10 Flowcharts PROCESS MAPPING (Written format)

11 Flowcharting Flowcharting is a graphical tool for analysing processes.
Constructing flowcharts leads to a better understanding of processes. Better understanding of processes is a essential for improvement Flowcharting allows you to break any process down into individual events or activities and to display these in shorthand form showing the logical relationships between them. It can be applied to any process from manufacturing chairs to the steps involved in checking into an hotel. The flowchart helps us understand the activities that make up a process and illustrates this clearly in a graphical form. The flowchart enables us to identify unnecessary loops or activities and to find opportunities for improvement. It also helps to identify critical activities within a process which may have a major impact on performance e.g. tasks which cause delay. One further benefit of flowcharting processes is that it enables you to standardise the way things are done.

12 Flowcharts Some standard symbols
Start or end An activity a decision point in the process. a point at which the flowchart connects with another process. An off page connection All records are identified The symbols used to represent each event come in various forms. (Such as boxes, circles, diamonds or other shapes, they may even be descriptions in words.) Connections between events are always represented by arrows showing the flow of activity and order they occur in. Symbols Oval = an event that will trigger or end an action, for example `receive telephone call’ Start point. ‘End call’, End point. rectangle = an event which is controlled within the process. Typically this will be a step or action which is taken. Diamond = a decision point in the process. Typically, the statement in the symbol will require a `yes' or `no' response and branch to different parts of the flowchart. Circle = a point at which the flowchart connects with another process. The name or reference for the other process should appear in the symbol. Main steps in Flowcharting Identify the process to be flowcharted and to give the chart a title. Begin to draw the chart by first describing the event which initiates the process (the 'trigger'). Then note down each successive action taken. Actions should be described in as few words as possible, but make sure the description is not ambiguous or unclear. When you reach a point at which the flowchart branches into a number of alternatives, and the resulting complexity threatens to overwhelm the exercise, choose the most important alternative to continue flowcharting with. The others can be terminated and dealt with in separate flowcharts. Assess if the stages are correct. Ask people involved with the process to check the flowchart.

13 FLOWCHART When a flowchart describes a process in which a number of different people, or functional areas are involved, it is can be difficult to see who is responsible for each step. A technique to show this, and for analysing the number of times a process is 'handed over', is to divide the flowchart into columns. Each column should be headed with the name of the person or function. Each time they carry out an action it should be shown in their column.

14 HACCP Hazard Analysis and Critical Control Points
Businesses are required to ‘identify any step in the activities of the food business which is critical to ensuring food safety and ensure that adequate safety procedures are identified, implemented, maintained, and reviewed.

15 Steps involved in HACCP
Identify the Hazard Identify points when you need to have control measures (control points) Decide what control measures are needed Implement those controls Monitor Light checks in dairy etc. Temperature records. Etc.

16 Exercise Draw / evaluate a flowchart for one of the following processes: Making a cup of coffee or tea Cutting the grass Booking a flight on-line Organising a surprise birthday party

17 3. Graphs & Histograms Graphs, in various forms are used to aid understanding and analysis of collected data sets.

18 This is the data set shown graphically.
Graphs BAR CHARTS This is the data set shown graphically. It highlights the major problems for all to see.

19 Graphs This graph shows production output for February.
This graph shows specific factors which could be analysed. What could you do in this case?

20 The graph below shows categories of customer complaint.
Graphs The graph below shows categories of customer complaint. Do you think the pie chart and the colours help to understand the data? the use of the pie chart and the colours enforce the message.

21 Rules for Graphing Use titles and indicate when the data was collected
Ensure the scales are clear and represent the data accurately. Always keep in mind the reason why the graph is being used.

22 Exercise Graphs You are the marketing director of XZY automotive, a new Scottish company. You have organised a local survey to rate your car against other small cars. 30 people were polled and the results are shown below. Xzy, ka, Clio, Clio, ka, fiesta, xzy, ka, 206, xzy, fiesta, fiesta, xzy, polo, fiesta, 206, 206, polo, 206, fiesta, fiesta, fiesta, polo, xzy, polo, fiesta, xzy, xzy, ka, xzy. You have decided to Graph the results as part of your marketing drive. Choose and explain your choice of graph.

23 What is a Histogram? The Histogram shows the distribution of one characteristic for one period of time. The Histogram is a tool for looking at data in groups rather than representing individual measurements. Units of measurement would be minutes, kilograms, millimetres.

24 Is this a histogram? What is a Histogram?
Checks/only record failures Total Power up 4 Boot up 15 Sink test 5 Case damage Keyboard damage Monitor damaged 3 Bundled s/w included 7 Is this a good example of a bar chart. No time, date, who collected it?

25 The answer to the previous question is NO
What is a Histogram? The answer to the previous question is NO The Histogram shows the distribution of one characteristic for one period of time. Although histograms show data values from a continuous range, they can also be used in the same way for discrete values i.e. number of defective parts, absenteeism, defectiveness etc. You may often see asymmetrical shapes (skewed distributions). Also look for Bi-model (two peaks) distributions and check stratification.

26 When is a Histogram Used?
To look at one particular set of results, for one characteristic at one period of time To look for patterns in a process To help understand data The purpose of a Histogram is to take the data that is collected from a process and graph it to show how the data is distributed. The histogram will show: The centre of the data. The spread of the data. The skew of the data (slant, bias or run at an angle). The occurrence of out of range conditions. The presence of peaks within the data.

27 Histograms The following data was collected when measuring the bow (warp) of a plastic component. The specification is less than 8 x10-3 mm (zero – 8). This can be plotted as a histogram because we have quantitative data and target limits. Bow measurements 2 5 8 4 6 7 9

28 Histograms 1 2 3 4 5 6 7 8 9 Bow (10-3mm) Frequency
1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 Bow (10-3mm) Frequency The table shows the data sorted and tallied up. The graph is a Histogram, showing that the components are not all within the limits and they are not centred correctly.

29 What is a Histogram? Exercise Sort the data about male weights into appropriate sets, then plot a histogram.

30 Separating the ‘vital few’ from the ‘trivial many’ Juran
4. Pareto Analysis Separating the ‘vital few’ from the ‘trivial many’ Juran

31 What is Pareto Analysis?
Pareto analysis is a method to help prioritise actions. It is a Bar Chart displayed in a particular way either in order of importance (frequency, relative cost, etc). If the symptoms or causes of a defect or some other “effect” are identified and recorded, it will be possible to determine what percentage can be attributed to any cause, and the probable results will be that the bulk (typically 80%) of the errors, waste or “effects”, derive from a few of the causes (typically 20%). Without an analysis of this sort it is all too easy to devote resources to addressing one symptom only because its cause seems immediately apparent. As someone once said “If the only tool you have is a hammer it is surprising how everything starts looking like a nail.” It is based on the assumption that a “vital few” sub-problems are the main contributors to an overall problem and that the “trivial many” sub-problems make only a minor contribution. Pareto Analysis is used to ensure that the” vital few” are tackled first and the “trivial many” are left for future examination.

32 Pareto Example: The information to be represented on a Pareto diagram normally would have already been collected. Household repairs over the last 10 years Problem frequency Cost £ per occurrence Total cost Light bulb fails 100 0.6 60 Broken central heating pump 1 190 Broken window 2 50 Leaking taps 16 2.5 40 Faulty central heating boiler 3000 Leaking radiators 3 15 45 Check sheets are a logical point to start in most process control or common problem solving efforts. It is particularly useful for recording direct observations and helping to gather in facts rather than opinions about the process. (The word faulty does not accurately describe the mode of failure and is open to opinion rather than being a fact.)

33 Pareto Pareto Chart The data are then displayed graphically. Firstly in terms of frequency..... House repairs 20 40 60 80 100 120 Light bulb fails Leaking taps radiators Broken window central heating Faulty Fault Occurence frequency Cum % Looking at this analysis it would appear that the biggest problem faced by the company is oversized spacers since it is the most re-curing problem. This would indicate that this should be the crucial problem in need of solution. However if we look at the following analysis...

34 ... and then by cost. Pareto House repairs 1998-2008 Total cost £ 500
500 1000 1500 2000 2500 3000 3500 Faulty central heating boiler Broken pump window Light bulb fails Leaking radiators taps Total cost £ Although oversize spacers is the most re-occurring problem it is useful to look at the method of correcting all these problems. In the case of oversize spacers these items are likely to be thrown away and replaced at minimal cost. All the other faults are likely to involve some sort of rework procedure - some more complicated than others. If we know look at this analysis it becomes apparent that the cost to correct one poor body coating far outweighs the cost of replacing all oversize spacers. In essence this suggests that poor body coating is the true vital problem which needs to be addressed.

35 Exercise Produce a Pareto Diagram for the data in the separate handout.
As always strongly advise participants to give these points adequate consideration.

36 6. Cause and Effect Diagrams (Ishikawa) using brainstorming
A method to help identification of the root causes of an effect (usually a problem). If something unexpectedly good happens you can also use Cause and effect to find out why in order to repeat.

37 cause and effect What is Brainstorming?
A way to get creative ideas. A way to get everyone’s views. A way to generate alternatives. Brainstorming is a technique used to generate a large number of ideas quickly, and may be used in a variety of situations. Each member of the group, perhaps in turn, may be invited to put forward ideas for the resolution of the issue at hand.

38 cause and effect Potential Uses (Brainstorming)
For identifying areas for improvement. For finding potential causes of problems. For developing possible preventive actions. Theoretically brainstorming can be applied to any form of idea generation. The above scenarios however are the ones most likely to be of some benefit to Keystone.

39 cause and effect Some Guidelines (Brainstorming)
Do’s Don'ts Give wild and unusual ideas. Aim for quantity. Build on ideas of others. Encourage participation. Evaluate or criticise. Stop to soon. Allow domination or idea ownership. Wild ideas are safe to offer, as criticism or ridicule is not permitted during a brainstorming session. In order to do this, the people taking part do so with equal status. The main objective is to create an atmosphere of enthusiasm and originality.

40 Simple Rules for Brainstorming
1. Works best with a group of six to twelve members. 2. Ideas are taken from one member at a time, in rotation. 3. Ideas are written on a flip chart or OHP transparency. 4. If a response is not immediately forthcoming the member should pass. 5. No idea is too obvious or stupid.

41 Simple Rules for Brainstorming
6. Ideas should not be enlarged upon at this stage. 7. The leader is there to lead the group, not to provide ideas. 8. The process is repeated until ideas dry up. 9. The ideas are then discussed and can be criticised but not the people that made them. 10. Eliminate the unlikely causes and identify those with high possibilities using cause screening - put those on a fishbone diagram.

42 Ranking Group discussion of likely causes and ease of fixing.
Individual selection of 3-5 most likely. Paired comparisons

43 Group discussion (Ranking)
Group discusses if each possible cause is N – Not likely S - Somewhat likely V - Very likely And the ease of fixing N - Not easy S - Somewhat easy V - Very easy

44 cause and effect Individual Ranking
Each person privately selects items from the list Each person ranks their selection in order of priority Allocate values of 1 most important, 2 next, 3 next, The marks are then totalled for each item The item having the lowest total is then judged to have the highest priority. This is purely an information slide. Try and make sure everyone in the group understands the process and be prepared to answer any questions which may arise.

45 Paired Comparisons The group preselects 6 – 8 most important causes.
Each person completes a paired comparison grid. Scores are added using a vote matrix. Highest score is most important

46 No. ITEM 1 2 3 4 5 6

47 ITEM NO. TEAM MEMBER VOTES TOTAL RANK 1 2 3 4 5 6

48 cause and effect What is a Cause and Effect Diagram?
The process of a cause and effect diagram consists of defining an effect in terms of possible causes and is normally carried out in the form of a Brainstorming session. The principal causes are typically Man, Materials, Methods or Machines. However you can also use Environment, Marketing, Management, Money etc. depending upon the exact situation. A useful way of identifying the inputs that effect quality is the cause and effect diagram. These diagrams are also known as Ishikawa diagrams after their originator, or fishbone diagrams after their appearance.

49 Cause and Effect Analysis
sub-causes can then be added Finally, the most likely causes are then identified for further investigation. These relationships are displayed pictorially in the form of a fishbone structure.

50 cause and effect Layout:
Method Man Sub-Cause Sub-Cause Sub-Cause Effect Sub-Cause Sub-Cause The effect or issue being investigated is shown at the end of a horizontal arrow. Potential causes are then shown as labelled arrows entering the main cause arrow. Each arrow may have other arrows entering it as the principal issues or causes are reduced to their sub-causes - perhaps by Brainstorming. Sub-Cause Materials Machines

51 Using Three Cause and Effect Diagrams
Present situation Desired final situation How to get from the present to the desired. Think about training. Present = not fully trained. Desired = fully trained., How = training course for how many by whom etc.

52 6. Scatter Diagrams A method for the identification of a possible relationship between two factors.

53 Scatter diagrams What is it used for?
Validating "hunches" about a possible cause-and-effect relationship between two variables. Displaying the direction of the possible relationship (positive, negative, etc.) Displaying the strength of the possible relationship

54 Scatter diagrams Constructing scatter diagram
In order to construct a scatter diagram you need two variables to be plotted against each other. One on the x-axis the other on the y-axis. Different values of variable b are then plotted against variable a. Variable b Variable a

55 Scatter diagrams Constructing scatter diagram
This process is continued, plotting different values as one variable changes. Number of bottles of vodka vs the number of lecturers employed Variable b Variable a

56 Scatter diagrams Interpreting a scatter diagram
The diagram below shows a Strong Positive correlation between the variables. Variable b Variable a

57 Scatter diagrams Interpreting a scatter diagram
The diagram below shows a Strong Negative correlation between the variables. Variable b Variable a

58 Scatter diagrams Interpreting a scatter diagram
The diagram below shows a Weak Positive correlation. Variable b Variable a

59 Scatter diagrams Interpreting a scatter diagram
The diagram below shows a Weak Negative correlation. Variable b Variable a

60 Scatter diagrams Interpreting a scatter diagram
The diagram below shows no correlation between the variables. Variable b Variable a

61 NOTE It is an important note that any positive or negative correlation does not mean that there is a cause and effect relationship between the variables. Only that there might be! EG both variable might change as the effects of another common cause – vodka and lecturers.

62 7. Control Charts A method for monitoring a process for preventing defects. Covered in a separate session by Esteban Fernandez

63 Problem Solving Steps Define Problem Collect Data Display Data
Analyse results Consider possible causes Identify possible solutions Experiment Implement and follow up

64 Problem Identification
Problem Analysis Problem Identification Flow chart Check sheet Brainstorming Cause and effect Pareto SPC Histogram Scatter Diagram

65 Problem Solving methods
5 Why Global 8D TRIZ

66 What is “5 Why” “5 Whys” is a problem solving technique that allows you to get at the root cause of a problem fairly quickly. It is used by automotive industry in Japan to determine the root cause of problems.

67 “Most problems do not call for complex statistical analysis but instead require painstaking, detailed problem solving This requires a level of detailed thinking and analysis that is all too absent from most companies in day to day activity” Yuichi Okamoto Toyota technical Centre

68 What is 5 Why? The “5 Why” technique is a very simple method of getting to the root of a problem When a problem occurs, we ask….WHY?…until the root cause is found. Five times is usually enough to get to the root of the problem! Once you find the root cause of a problem it’s much easier to put in sound corrective action to prevent it happening again

69 Advantages If the correct “Why” questions are asked in succession to the correct people he or she will find at least one root cause of the problem. It only takes short time to perform i.e. 5 to 10 mins There are no special tools or software required. It can make people have a new way of thinking out problems.

70 Disadvantages It usually only leads to one of the root causes so need to repeat the process Sometimes you need to go through process several times to find all the causes which can require some skill from the question maker. It does not always point you in the direction of generic causes e.g. training issues.

71 Here’s How It Works!!! Man is late for work PROBLEM: WHY?
Because his car stopped WHY? Because it ran out of petrol WHY? Because he did not buy any on the way to work WHY? Because he had no money WHY? Because he lost it all in a game of poker Solution: Stop playing poker!!!!

72 Global 8D D0 Prepare D1 Use the team approach D2 Describe the problem
D3 Implement and verify interim containment action D4 Identify and Verify root causes D5 Choose and Verify corrective action D6 Implement Corrective Action D7 Prevent recurrence – close the loop D8 Recognition


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