What is 7QC tools ? | what are the 7QC tools?

What is 7QC tools? and What are the 7 Qc tools?

7QC Tools

7QC tools is basic quality control tools which helps to troubleshoot quality related issues. 7QC tools mostly includes graphical techniques to analysis or solve the problems related to quality. 

It consist of check sheets, flow charts, control charts, histogram,scatter diagram, Pareto diagram, cause and effect diagram, 7QC tools are suitable for those who took formal little training in statistics.

Quick explanation and advantages of each tools are given below.

1. Check sheet

It is type of documents or form used to collect raw data in real time from particular place by particular person. Check sheets consist of short information such as who filled out check sheet, why data were collected, what was collected, where the collection take place, when the collection took place. 

The collected data are in Quantitative data or Qualitative data. Main purpose of check sheet is to collect data for further analysis

Advantages of Check sheets are as follow.

1. Easy to find defect by type.

2. Easy to track defect by particular cause.

3. Easy to keep daily work completion records.

4. Easy to find real time defect in continuous process.

2. Flow chart

It is type of diagram which show step by step workflow or particular process from start to end. This steps in flowchart are various kind of boxes and their order are shown by arrow connected to boxes. Flow Charts are used in documenting, designing and analyzing process. 

There are various types of flow charts according to their uses such as System flow chart,Program flowcharts, Data flowcharts, Document flowcharts.

Advantages of flow chart are as follow.

1. Whole workflow in single diagram.

2. Easy to find steps in order from start to end.

3. Difficult process can be explained easily.

3. Histogram in 7qc tools

It is a type of Quality control tool which is commonly used graphs to show frequency distribution. It was first described by Karl Pearson show often each different value in set of data occur.

A Histogram is created by dividing up the range of collected data into small number of intervals or bins. Then counting is made on number of observation falling into each interval. This gives a frequency distribution. 

It is type of x-y graph which represents number of counts on vertical axis 'Y' and possible range of data values on horizontal axis 'X'.

Advantages of histogram are as follows

1. Easy to summarize large data sets graphically.

2. Easy to compare process results with specifications limit.

3. It can be tool use to assist in decision making.

4. Scatter Diagram

It is diagram which shows correlations between two quantitative variables. In Scatter diagram, correlations are categorized into three category (Linear,Non linear and No correlation).

Linear correlation means variables that are correlated through a linear relationship can display either positive or negative correlation. 

Non linear correlation means two variables may be correlated but not a linear model, this is called Non linear correlation. Two quantitative variables may not be correlated at all, then called as No Correlation.

Correlation may be strong, moderate or weak.

You can determined the correlation strength by drawing line throughout variation and observing variation of points around line. 

Large variation is weak correlation.when the data is distributed quite closer to line, then correlation set to be strong. If the variation of data not large or nor closer to line, it can be moderate.

5. Pareto Chart

It is chart based on Pareto principle which is discovered by an italic economist "Vilfredo Pareto(1848-1923)" who observed that 80% of wealth was owned by only 20% of population, this was true in almost all the society he studied. 

A Pareto chart is type of chart that contains both bars and line graph, where individual values are represented in descending order by bar, and cumulative total is represented by the line.

The main purpose of Pareto chart is to highlight the most important among a set of factors. Pareto chart is mostly used in manufacturing industries.

6. Control charts

It is also called Process behavior charts. It is used to determine whether a process should undergo a formal examination for quality related problems. The control chart is one of 7QC tools used for time series data, though they can be used for data that have logical comparability.

7. Cause and Effect diagram

It is also called as fish bone diagram or Ishikawa diagram. It was first created by "Kaoru Ishikawa" that shows cause of specific event. 

Cause and Effect diagram examines why something happened or might happen by organizing potential causes into smaller categories. From this diagram, we get actual root cause of particular event.

How to be good in 7QC tools?

Understanding of 7QC tools will be based on your basic mathematics skills."What did you learn from your 10th standard mathematics?" will be used in this tools. After 10th standard, most of students are confused about "What to do after 10th ?".

If you are good in Basic Mathematics and want to be experts in 7QC tools, choose your future study in field of statistics. It will definately helps you to expert in 7QC tools?