The seven tools of quality

The seven tools of quality are as follows :

1. Cause and effect diagram
2. check sheet
3. control chart
4. histogram
5. Pareto diagram
6. scatter diagram
7. flow chart or run chart

Cause and effect diagram:

• It examines why something happened or might happen by organising the potential causes into categories.
• The entire diagram ends up like a fish bone with the problem to the right as the head and the catergories to the left as the skelton of the fish so it is also known as fish bone diagram.
   
  Check sheet:
  • It is a dociment where the data is collected from its origin point.
  • if the data is quantitative the check sheet will be referrred as tally sheet.
  • In a defective check sheet two factors will be recorded type of defect and origin of  defect.
    
     
  Control chart:
  • The control chart is used to collect the data and analyse the process to be studied.
  • It ensures wheather the process is under control.
  • The chart has center line which is mid line and there is a upper control limit and lower control limit.
  
  
  
    Histogram:
  • It is the accurate representation of the data distribution in a process.
  • it is represented in the bar charts often.
  • On the x axis the range of the values are plotted and in y axis the number of times the data fall in that range is denoted.
    
    
     
    Pareto Diagram:
    • Shows in bar chart which problem or area of problem is more significant.
      
    Scatter diagram:
    • It show the relationship the two variables.
      

    Flow chart:
    • It represents the entire work flow of the firm or the work flow of the particular workstation.