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QUALITY TOOLS AND TECHNIQUES
Team Members:
SEWOORAZ Rajiv 0815666
SHIBLOLL Doosheeka 0813310
SOOKLALL Hammaade 0811861
SOOKHARRY Tinaraj 0811879
SOOKRAH Rajiv 0810474
Definition of Total Quality Management (TQM) in terms of tools and techniques.
The different components used to accomplish the aim of a system
1. Core Values 2. Techniques 3. Tools
Any system should have an aim:
Freigenbaum (1991) Deming (1994) and Juran (1994) Hellsten and Klefsjo (2000)
Figure A: Role of core values, techniques and tools
Source: TQM as a Management System consisting of values, techniques and tools. The TQM magazine, volume 12 issue 4, pp242
TECHNIQUES VS TOOLS
Techniques and tools differ from each other.
Examples: 1. Core values: Let everybody be committed
2. Core value: Focus on process
3. Core values: Focus on customers
FAILURE OF TECHNIQUES AND TOOLS
Failures arise when:
1. There is lack of top management commitment
2. only part of the system is taken into consideration and using only one or few techniques and tools
3. No Quality Culture
SELECTING TOOLS AND TECHNIQUES
Role of Tools and Techniques
Two important factors that an organisation needs to be considered when selecting tools:
1. Not in isolation 2. No one tool or technique is more important
than another
PRECAUTIONS TO BE TAKEN WHEN SELECTING TOOLS AND TECHNIQUES
1. To know the tools or techniques that are being selected
2. Not to choose any tools or techniques randomly
3. Lack of motivation
SOME TOOLS
1. Check sheets/tally sheets 2. Histograms 3. Scatter Diagram 4. Stratification 5. Flowchart 6. Pareto Analysis 7. Cause and Effect Analysis
CHECK SHEETS OR TALLY SHEETS
CHECK SHEETS OR TALLY SHEETS
According to Oakland (2003) It is a simple form for collecting data in an organized manner and easily convert it into readily useful information.
The function of a check sheet is to present information in an efficient, graphical format.
A check sheet is a table or a form used to systematically register data as it is collected.
Check sheets help organize data by category
They show how many times each particular value occurs, and their information is increasingly helpful as more data are collected.
Main applications of a check sheet include registering how often different problems occur and registering the frequency of incidents that are believed to cause problems.
ADVANTAGES OF USING A CHECK SHEET:
Effective way of displaying data Easy to use Can identify the root cause of a problem A first step in the construction of other
graphical tools Provides a structure for uniform data
collection Can be used to substantiate or refute
allegations
Histograms
HISTOGRAMS
Oakland (2003) stated that histograms show, in a very clear pictorial way, the frequency with which a certain value or group of values occurs.
They can be used to display both attribute and variable data, and are an effective means of letting the people who operate the process know the results of their efforts.
ADVANTAGES OF USING HISTOGRAM:
Visually strong. Gives immediate information
Can be compared to a normal distribution curve when the data is large
Vertical axis is used to represent count of items falling into each category
DISADVANTAGES OF HISTOGRAM:
Exact values are not known as the data is grouped into categories/groups to draw the bar graph
Difficult to compare two data sets
Use only with continuous data
Representation of the frequency distribution depends upon the number of categories selected.
Multiple histograms can be drawn for the same data making it difficult to read and interpret.
SCATTER DIAGRAMS
SCATTER DIAGRAMS
A scatter diagram is a tool for analyzing relationships between two variables. One variable is plotted on the horizontal axis and the other is plotted on the vertical axis.
The pattern of their intersecting points can graphically show relationship patterns. Most often a scatter diagram is used to prove or disprove cause-and-effect relationships.
While the diagram shows relationships, it does not by itself prove that one variable causes the other.
In addition to showing possible cause and-effect relationships, a scatter diagram can show that two variables are from a common cause that is unknown or that one variable can be used as a surrogate for the other.
STRATIFICATION
STRATIFICATION
Oakland (2003) stated that stratification is simply dividing a set of data into meaningful groups.
It can be used to great effect in combination with other techniques, including histograms and scatter diagrams. If, for example, three shift teams are responsible for a certain product output ‘stratifying’ the data into the shift groups might produce histograms that indicate ‘process adjustments’ were taking place at shift changeovers.
CONTROL CHARTS
CONTROL CHARTS
A control chart is a statistical tool used to distinguish between variation in a process resulting from common causes and variation resulting from special causes. It presents a graphic display of process stability or instability over time.
One goal of using a Control Chart is to achieve and maintain process stability.
WHY USE CONTROL CHARTS?
Control Charts help you monitor the behavior of your process to determine whether it is stable.
A team will benefit from using a Control Chart when it wants to:
Monitor process variation over time.
Differentiate between special cause and common cause variation.
Assess the effectiveness of changes to improve a process.
Communicate how a process performed during a specific period.
WHAT ARE THE TYPES OF CONTROL CHARTS?
There are two main categories of Control Charts, those that display attribute data, and those that display variables data.
Attribute Data: This category of Control Chart displays data that result from counting the number of occurrences or items in a single category of similar items or occurrences. These “count” data may be expressed as pass/fail, yes/no, or presence/absence of a defect.
Variables Data: This category of Control Chart displays values resulting from the measurement of a continuous variable. Examples of variables data are elapsed time, temperature, and radiation dose.
TYPES OF CHARTS
For variables mean (X) and range (R) charts are used together; number of defective or np charts and proportion detective or p charts are the most common ones for attributes.
Other charts found in use are moving average and range charts, numbers of defects (c and u) charts, and cumulative sum (cusum) charts. The latter offer very powerful management tools for the detection of trends or changes in attributes and variable data.
STATISTICAL PROCESS CONTROL
STATISTICAL PROCESS CONTROL
Statistical process control (SPC) is the application of statistical methods to the monitoring and control of a process to ensure that it operates at its full potential to produce conforming product.
Under SPC, a process behaves predictably to produce as much conforming product as possible with the least possible waste. While SPC has been applied most frequently to controlling manufacturing lines, it applies equally well to any process with a measurable output.
Much of the power of SPC lies in the ability to examine a process and the sources of variation in that process using tools that give weight to objective analysis over subjective opinions and that allow the strength of each source to be determined numerically.
Variations in the process that may affect the quality of the end product or service can be detected and corrected, thus reducing waste as well as the likelihood that problems will be passed on to the customer.
With its emphasis on early detection and prevention of problems, SPC has a distinct advantage over other quality methods, such as inspection, that apply resources to detecting and correcting problems after they have occurred.
In addition to reducing waste, SPC can lead to a reduction in the time required to produce the product or service from end to end.
This is partially due to a diminished likelihood that the final product will have to be reworked, but it may also result from using SPC data to identify bottlenecks, wait times, and other sources of delays within the process.
Process cycle time reductions coupled with improvements in yield have made SPC a valuable tool from both a cost reduction and a customer satisfaction standpoint.
PARETO ANALYSIS
•Pareto analysis is used to differentiate between the vital few and the trial many.•It is based on the concept that 80% of the problems come from 20% of the items.•Pareto analysis shows where process improvement should begin- those problem area with the greater frequency
STEPS IN CREATING A PARETO ANALYSIS
Step 1: Form an explicit table listing the causes and their frequency as a percentage.
Step 2: Arrange the rows in the decreasing order of importance of the causes (i.e., the most important cause first)
Step 3: Add a cumulative percentage column to the table
Step 4: Plot with causes on x- and cumulative percentage on y-axis
Step 5: Join the above points to form a curve Step 6: Plot (on the same graph) a bar
graph with causes on x- and percent frequency on y-axis
Step 7: Draw line at 80% on y-axis parallel to x-axis. Then drop the line at the point of intersection with the curve on x-axis. This point on the x-axis separates the important causes (on the left) and trivial causes (on the right)
Step 8: Explicitly Review the chart to ensure that at least 80% of the causes are captured
CAUSE AND EFFECT DIAGRAM A Cause-and-Effect Diagram, also known as a
"Fishbone Diagram“ or the Ishikawa diagram is a graphical technique for grouping people's ideas about the causes of a problem.
The cause and effect diagram is used to explore all the potential or real causes (inputs) that result in a single effect (output).
Causes in a cause & effect diagram are frequently arranged into four major categories:
manpower, methods, materials, and machinery (for manufacturing)
equipment, policies, procedures, and people (for administration and service).
TYPES OF CAUSE AND EFFECT DIAGRAM
There are 3 Types of cause and effect diagram Dispersion Analysis Diagram Production Process Classification Diagram Cause Enumeration Diagram
DISPERSION ANALYSIS DIAGRAM
PRODUCTION PROCESS CLASSIFICATION DIAGRAM
STEPS IN A CAUSE AND EFFECT DIAGRAMThere are namely 4 steps in a cause and effect
diagram: identify the problem's characteristics brainstorm the reasons why the problem is
occurring using a Causal Table (also known as the Why-Because Technique)
group the causes by relationship using an Affinity Technique
create a Cause-and-Effect Diagram
POSSIBLE COSTS OF QUALITY TOOL AND TECHNIQUE
Tools and techniques are used in quality in the quest for improvement in the ways processes are operated.
The possible costs that may occur are: Training commitment and leadership rivalry between departments
BRAINSTORMING
Steps:• Define your problem or issue as a creative
challenge• Give yourself a time limit• Shout out solution at the problem• Select best five ideas which you like the best• Write down five criteria for judging which
idea best solve your problem• Score each 0-5• Highest score will best solve your problem
PROCESS FLOWCHARTING
It ensures a full understanding of the inputs and flows of the process.
No single person is able to complete a chart without help from others. This makes a powerful team-forming exercise
MANAGEMENT TOOLSMANAGEMENT TOOLS
Aims towards process owners and operatives
Effective for teams, and in some cases, for individuals
Useful for: process improvement Policy deployment New-product development
Why-Why Diagram
How it works
How to do it
WHY-WHY-WHY DIAGRAMWHY-WHY-WHY DIAGRAM
FORCE-FIELD ANALYSIS FORCE-FIELD ANALYSIS
When to use it
HOW TO USE ITHOW TO USE IT
Draw the outline diagram
Plot opposing forces
Draw conclusions
EXAMPLEEXAMPLE
A team at a steel mil is seeking to save money. They come up with a
consolidation idea, but know that it may be opposed, so they use Force-Field Analysis to explore reasons why the idea will or will not be supported.
EXAMPLEEXAMPLE
NOMINAL GROUP TECHNIQUE NOMINAL GROUP TECHNIQUE
When to use it
HOW TO USE ITHOW TO USE IT
Clarify objective
Silent writing of ideas
Share and understand
Vote
RELATIONS DIAGRAM/ RELATIONS DIAGRAM/ INTERRELATIONSHIP DIAGRAM OR INTERRELATIONSHIP DIAGRAM OR DIGRAPH/NETWORK DIAGRAM DIGRAPH/NETWORK DIAGRAM
When to Use a Relations Diagram
Relations Diagram Basic Procedure
EXAMPLE OF RELATIONS EXAMPLE OF RELATIONS DIAGRAM DIAGRAM
MATRIX MATRIX DIAGRAM/MATRIX/MATRIX CHART DIAGRAM/MATRIX/MATRIX CHART
The matrix diagram shows the relationship between two, three or four groups of information. It also can give information about the relationship, such as its strength, the roles played by various individuals or measurements.
ARROW DIAGRAM /ACTIVITY NETWORK DIAGRAM/ ARROW DIAGRAM /ACTIVITY NETWORK DIAGRAM/ NETWORK DIAGRAM /ACTIVITY CHART/ NODE NETWORK DIAGRAM /ACTIVITY CHART/ NODE
DIAGRAM/CPM (CRITICAL PATH METHOD) CHART DIAGRAM/CPM (CRITICAL PATH METHOD) CHART
When to Use an Arrow Diagram
DRAWING THE NETWORK DRAWING THE NETWORK
1 List all the necessary tasks in the project or process
2 Determine the correct sequence of the tasks3 Diagram the network of tasks4 Between each two tasks, draw circles
for “events”5 Look for three common problem
situations and redraw them using “dummies” or extra events
6 label all events in sequence with event numbers in the circles
7 Determine task times
DRAWING THE NETWORK DRAWING THE NETWORK
8 Determine the “critical path,” the longest path from the beginning to the end of the project
9 Calculate the earliest times each task can start and finish, based on how long preceding tasks take
10 Calculate the latest times each task can start and finish without upsetting the
project schedule, based on how long later tasks will take
DRAWING THE NETWORK DRAWING THE NETWORK
11. Calculate slack times for each task and for the entire project
Total slack = LS – ES = LF – EF
VIEW EXAMPLE OF A COMPLETED ARROW DIAGRAM.
CONCLUSION
A tool is a device which has clear role and defined application. Tools and techniques are used in quality in the quest for improvement in the ways processes are operated. Normally all the tools are basically simple but their inappropriate selection and application often end up in failure.
QUESTION TIME?
