Statistical Quality Control -Frequency Curve
Posted by mechlook info on November 16th, 2011 07:36 PM | No Comment
Frequency Curve
If the number of observations were very much larger and if the groups were made much narrower, then the histogram approaches a smooth curve for the frequency distribution of observations On outside diameter measurement on 15/40 stop volve.
The frequency ...
Statistical Quality Control -Variations in Quality
Posted by mechlook info on November 16th, 2011 07:36 PM | No Comment
Variations in Quality
Variation in quality characteristic is inevitable, however well the process may be controlled and tests carried out Thus, for example, measurements taken on some components are bound to vary from piece to piece even though the process may ...
Statistical Quality Control -Summarisation and Pictorial Presentation of Data
Posted by mechlook info on November 16th, 2011 07:36 PM | No Comment
Summarisation and Pictorial Presentation of Data
In inspection of any item, many observations are required to be taken and thus it results in the accumulation of so many numbers. Obviously it is very difficult for human being to conclude anything or ...
Statistical Quality Control -Some Statistical Measures
Posted by mechlook info on November 16th, 2011 07:35 PM | No Comment
Some Statistical Measures
The various useful statistical measures are average (arithmetic mean), Hinge, standard deviation etc. Arithmetic mean represents the measure of central tendency. If a1, a2, an are the values of n items observed, then arithmetic mean.
ā=a1+a2 + a3 +…. ...
Statistical Quality Control -Data Presentation
Posted by mechlook info on November 16th, 2011 07:35 PM | No Comment
Data Presentation
In all the Industries, volumes of data are collected every day on the various aspects. These data are collected to serve as the base material for making useful and meaningful decisions. The inspectors or supervisors collect data on the ...
Statistical Quality Control-Introduction
Posted by mechlook info on November 16th, 2011 12:07 AM | No Comment
Introduction
It has been the aim of engineers to strive at higher and higher accuracy, but absolute accuracy is unattainable. Every process and its output are subject to variation. No two things can be made exactly alike. In mass-production, therefore, no ...