Action and Warning Lines for Shewart Chart for Ranges

Group Size

Action Lines

Warning Lines

2

0.00

4.12

0.04

2.81

3

0.04

2.99

0.18

2.18

4

0.10

2.58

0.29

1.94

5

0.16

2.36

0.37

1.80

6

0.21

2.22

0.42

1.72

7

0.26

2.12

0.46

1.66

8

0.29

2.05

0.50

1.62

9

0.33

1.99

0.52

1.58

10

0.35

1.94

0.54

1.55

The action and warning lines are obtained bymultiplying the values in the table by the mean range of thevalues obtained from the process.