case study addu

8/11/2019 Case Study Addu

1/19

CASE STUDY

Sterlite Industry India Ltd.: Success Through Total Quality Management

Sterlite industry ltd. Install a Copper Rod Plant for making products:

1 Copper Cathodes

2 Copper Rods

It acquire 43% of market share in 2005-06

The business is further divided into 3 categories:

1 Copper Business (SIIL)

1,78,000 tn in 2007 7% increase in as compared to2006

2 Zinc Business (HZL)3 Aluminum Business (BALCO)

3,13,000 tn 2007 80% increase in as compared to 2006


2/19

Restructuring the projects:

A.(SILL):

1 Copper

2 Zinc

3 LEAD

B.(MALCO):

1 Energy

2 Aluminum OperationsC.(Seas Goa)

1 Iron ore

After this Vedant Group become the world 5 largest aluminum

producer 2012moreover, it become the 10 largest producer of iron ore

For improving the quality co. launches 26 new improvement project

in 2006-07


3/19

Questions

1. The company has installed a new machine inone of the plants for producing 1 meter long

copper rods. To check the quality of product, the

company's control officer has taken a random

sample of copper rods after every hour. A totalof 7 sample of size 6 are taken & length is

recorded .data are given in the following table

.construct an X chart & R chart using the data


4/19

Sample

no.

x1 x2 x3 x4 x5 x6

1 .98 1.00 .99 .99 .98 1.00

2 .97 .99 .98 .99 1.00 .98

3 .97 .98 .97 .96 .99 1.00

4 .99 .98 .99 1.00 .98 .97

5 .98 .97 .99 .98 1.00 .99

6 .98 .97 .98 1.00 .99 .96

7 1.00 1.00 .99 .99 .96 .98


5/19


6/19

Calculation of x-bar and R-bar

Now,

98.07

89.6

m

xX

03.7

22.

m

RR

6


7/19

Control limits of

X-BarChart

Central line C.L

U.C.L =

=.98 + ( .48)( .03)

=.99

L.C.L=

=0.98 - (0.48) (0.03)

= .96

RAx *2

RAX *2

98.x

7

Factor for x-Chart

A2 D3 D4

2 1.88 0.00 3.27

3

1.02

0.00

2.57

4 0.73 0.00 2.28

5 0.58 0.00 2.11

6 0.48 0.00 2.00

7 0.42 0.08 1.9

28 0.37 0.14 2.86

9

0.34

0.18

1.82

10 0.31 0.22 1.78

11 0.29 0.26 1.74

12 0.27 0.28 1.72

13 0.25 0.31 1.69

14 0.24 0.33 1.67

15

0.22

0.35

1.65

Factors for R-ChartSample Size

(n)


8/19


9/19

Control limits of R-BarChart

Central Line =

U.C.L =

=0.06

L.C.L =

=0

03.0R

)03.0()004.2(4 RD

)03.0()0(3 RD

9

Factor for x-Chart

A2

D3

D4

2 1.88 0.00 3.27

3 1.02 0.00 2.57

4 0.73 0.00 2.28

5 0.58 0.00 2.11

6

0.48

0.00

2.00

7 0.42 0.08 1.9

28 0.37 0.14 2.86

9 0.34 0.18 1.82

10 0.31 0.22 1.78

11 0.29 0.26 1.74

12

0.27

0.28

1.7213 0.25 0.31 1.69

14 0.24 0.33 1.67

15 0.22 0.35 1.65

Factors for R-ChartSample Size

(n)


10/19


11/19

2. The company has received an order to supply

copper rods form a well-reputed company.

For maintaining quality, the companyscontrol officer has taken a random sample of

size 30 with 150 copper rods in each sample.

The following table provides data relating tothe number of defective rods in a sample of

size 30 with 150 rods. With the help of this

data, construct a P chart


12/19

sample n defective

1 150 1

2 150 2

3 150 1

4 150 3

5 150 1

6 150 2

7 150 3

8 150 0

9 150 0

10 150 0

11 150 1

12 150 2

13 150 3

14 150 2

15 150 1

sample n defective

16 150 3

17 150 3

18 150 3

19 150 0

20 150 0

21 150 2

22 150 0123 150 1

24 150 0

25 150 3

26 150 2

27 150 1

28 150 2

29 150 0

30 150 0


13/19

Sample n Defective D/N

1 150 1 0.006

2 150 2 0.013

3 150 1 0.006

4 150 3 0.020

5 150 1 0.006

6 150 2 0,0137 150 3 0.020

8 150 0 0

9 150 0 0

10 150 0 0

11 150 1 0.006

12 150 2 0.013

13 150 3 0.020

14 150 2 0.013

15 150 1 .0006

sam

ple

n defective Fraction

defective

16 150 3 0.020

17 150 3 0.020

18 150 3 0.020

19 150 0 0

20 150 0 0

21 150 2 0.01322 150 0 0.0

23 150 1 0.006

24 150 0 0

25 150 3 0.020

26 150 2 0.013

27 150 1 0.006

28 150 2 0.013

29 150 0 0

30 150 0 0

Solution:-


14/19

Control limits of pChart

Central line C.L =

U.C.L = =

=o.017

L.C.L= =

=0.001

n

ppP

)1(3

n

dP

4500

42

009.0

009.0P

150

)009.01(009.03009.0

n

ppP

)1(3

150

)009.01(009.03009.0


15/19


16/19

3. Suppose as part of a quality control exercise,

the company has taken a random sample of

30 copper cathodes & examined the numberof defects in these pieces . The result are

displayed below. Use the data to construct a

C chart


17/19

Copper No. of Defects(c)

1 0

2 03 0

4 0

5 1

6 1

7 2

8 1

9 1

10 0

11 1

12 2

13 0

14 2

15 2

Copper No. of Defects(c)

16 1

17 118 1

19 1

20 0

21 0

22 0

23 0

24 1

25 2

26 1

27 1

28 1

29 2

30 0


18/19

Solution:-

N

CC

30

25 8.0

CC 3UCL 8.038.0

5.3

LCL CC 3 8.038.0

9.1

Control limits of cChart

0

CL 8.0C


19/19

case study addu

Documents