Quality Engineering

OBJECTIVES
• To analysis the data of SD Slot Card dimension.
• To countermeasure design problem in dimension specification confirmation.
• To achieve the tolerance specification by using statistical methods.

SCOPE
This project was conduct for:
• All 12 samples have to take dimension measurement every each SD card slot .
• To countermeasure the defect product in order to achieve tolerance by using Statistical Process Control (SPC).
• The specification is defined as an Upper Control Limit (UCL) and Lower Control Limit (LCL) value from X-bar and R-bar chart.
• To identify that dimension whether in or out of specification.
• Difference value X and Y have to calculate. Then, all difference value of samples was calculated to get an average.
• The result will be proceeding with modification on design to adjust the SD card slot placing at the front cab panel.

RESULT AND CALCULATION

A data sample for the X-axis SD card slot

Sample X 1 2 3 4 5 X=average R=range
1 4.26 4.13 4.06 4.34 4.39 4.236 0.33
2 4.43 4.40 4.43 4.23 4.42 4.382 0.2
3 4.30 4.27 4.28 4.46 4.41 4.344 0.19
4 4.57 4.12 4.42 4.46 4.45 4.404 0.45
5 4.36 4.42 4.28 4.38 4.34 4.356 0.14
6 4.33 4.36 4.34 4.39 4.35 4.354 0,06
7 4.26 4.13 4.07 4.34 4.44 4.248 0.37
8 4.43 4.40 4.43 4.42 4.39 4.414 0.36
9 4.37 4.28 4.27 4.41 4.39 4.344 0.13
10 4.57 4.12 4.34 4.45 4.39 4.374 0.12
11 4.36 4.42 4.06 4.34 4.13 4.262 0.36
12 4.33 4.36 4.46 4.06 4.17 4.276 0.40
All units in mm

1-a) Calculation and X-bar graph for x-axis SD card slot = 51.994 12 = 4.333

= 3.05 12 =0.254

= 4.333 + (0.77×0.254) = 4.529

= 4.333- (0.77× 0.254) =3.817

1-b) Calculation and R-chart graph for X-axis SD card slot

= 1.72×0.254 = 0.437

= 0.28×0.254 = 0.071

Data sample for Y-axis SD card