This document provides an introduction to quality tools and strategies, including Six Sigma. It discusses defining critical to quality factors, calculating defects per million opportunities (DPMO), converting DPMO to a Sigma rating, and using the Six Sigma conversion table. The document also provides an example of calculating DPMO for a company's production and defining a quality improvement strategy to reach a higher Sigma level for future production. This includes determining the defect limit and interval for intensive inspection.
16. Approaching Six Sigma strategy
Let :
Total product manufactured be Tp
Total Critical to Quality be n
Critical to quality be i
Defects total be d
Defects per group be di THEN the DPMO is
n
Σdi
i=1
DPMO = X 1000.000
Tp x n
17. Approaching Six Sigma strategy
IBM computer manufacturing produces 54.998 IBM 5100 at the
beginning of 1975. The CTQ define as 2 groups of requirements
which is speed must be more than 975 Mhz, and the CPU unit must
not be more than 24 C when operating. Group speed defects 8900,
and temperature group defects 8876. define the DPMO.
n
DPMO = Σdi
i=1
X 1000.000
Tp x n
18. Approaching Six Sigma strategy
Let:
Total product manufactured be Tp = 54.998
Total Critical to Quality be n = 2 groups of requirements
Critical to quality be i = speed and temperature
Defects total be d = d1+d2
Defects per group be d1= 8900 , and d2=8876
8900 + 8876
DPMO = x 1000.000
54998 x 2
22. Quality Improvement Strategy
For Production Plan up to 1000.000 products next period
Assumption of defects OP per unit= 1-(success rate/100) = 0.184
Assumption of defects OP per period = 0.184 x 1000.000 = 184.000
Assumption of success OP per period = 0.816 x 1000.000 = 816.000
Success rate = 81.6 %
Sigma term = 2.40
Next plan : upgrading to sigma 2.50!
24. Approaching Six Sigma strategy
The six sigma term = 2.50
Success rate = 84.1 %
DPMO = 158.655
Gap = DPM(currnt)-DPM(2.50)
= 161.605 – 158.655
= 2950 defects
25. Approaching Six Sigma strategy
Gap percentage = (2950 / DPMO trget)
= (2950 / 158.655)
= (1.859%)
26. Quality Improvements Strategy
We get :
Total product manufactured be Tp = 1000.000
Total Critical to Quality be n = 2 groups of requirements
Critical to quality be i = speed and temperature
Defects total be d = d1+d2
Defects per group be d1= X1 , and d2=X2
DPMO =
X1 + X2
158.655 = x 1000.000
1000.000 x 2
27. Approaching Six Sigma strategy
Total unit = 1000.000 units
Defects limit = 317.310 units
Intensive inspection = 1.859 % x 1000.000
= per 18.590 units
28. Intensive inspection method
Introduction to FMEA (Failures Modes and Effect Analysis)
Intensive inspection regarding the defects after (n) units
To overcome the cases and compare the next inspection for (2n) units
Quality inspection ROUTINES
- Check the list of inspection (based on the CTQ)
- Inspect the procedure of most occurs defects product ex: prod line/treatment
- Do Research and Development to try other method
29. Intensive inspection method
The product is NON conformity
Why? (1)
The CPU is hot over the limit
Why? (2)
The heat sink is not attached perfectly
Why? (3)
The shock cause it loose
Why? (4)
The screw is not tight enough
Why? (5)
NEED loctite for it
31. Quiz?
Introduction to FMEA (Failures Modes and Effect Analysis)
A SPARK timetravel machine industry produces 263 timetravel (TT)
machines. They consider the microsingularities supply must not be higher
than 9 Giga joules and the jump speed must not be less than 10yrs/hr to
make the TT machines effective. After the end of the period, SPARK found
34 of their machines are considered as defects. Define what SIX SIGMA
term they are in. and if the SPARK would like to produce 6578 machines in
the next period, what is their defect limit? and per how many machines they
must do the intensive inspection ?